Merge

35 files changed, 1846 insertions, 2552 deletions

diff --git a/Binaries/DafnyPrelude.bpl b/Binaries/DafnyPrelude.bpl
index fef8fe1f..53d0b471 100644
--- a/Binaries/DafnyPrelude.bpl
+++ b/Binaries/DafnyPrelude.bpl
@@ -500,6 +500,13 @@ axiom (forall f: Field BoxType, i: int :: { MultiIndexField(f,i) }
 

 function DeclType<T>(Field T): ClassName;

 

+type NameFamily;

+function DeclName<T>(Field T): NameFamily;

+function FieldOfDecl<alpha>(ClassName, NameFamily): Field alpha;

+axiom (forall<T> cl : ClassName, nm: NameFamily :: 

+   {FieldOfDecl(cl, nm): Field T}

+   DeclType(FieldOfDecl(cl, nm): Field T) == cl && DeclName(FieldOfDecl(cl, nm): Field T) == nm);

+

 // ---------------------------------------------------------------

 // -- Allocatedness ----------------------------------------------

 // ---------------------------------------------------------------

diff --git a/Source/Dafny/Compiler.cs b/Source/Dafny/Compiler.cs
index e72c04dd..7f48e551 100644
--- a/Source/Dafny/Compiler.cs
+++ b/Source/Dafny/Compiler.cs
@@ -66,7 +66,7 @@ namespace Microsoft.Dafny {
       ReadRuntimeSystem();

       CompileBuiltIns(program.BuiltIns);

 

-      foreach (ModuleDecl m in program.Modules) {

+      foreach (ModuleDefinition m in program.Modules) {

         if (m.IsGhost) {

           // the purpose of a ghost module is to skip compilation

           continue;

@@ -91,7 +91,7 @@ namespace Microsoft.Dafny {
             wr.WriteLine(" { }");

             CompileDatatypeConstructors(dt, indent);

             CompileDatatypeStruct(dt, indent);

-          } else {

+          } else if (d is ClassDecl) {

             ClassDecl cl = (ClassDecl)d;

             Indent(indent);

             wr.Write("public class @{0}", cl.CompileName);

@@ -101,7 +101,9 @@ namespace Microsoft.Dafny {
             wr.WriteLine(" {");

             CompileClassMembers(cl, indent+IndentAmount);

             Indent(indent);  wr.WriteLine("}");

-          }

+          } else if (d is ModuleDecl) {

+            // nop

+          } else { Contract.Assert(false); }

         }

         if (!m.IsDefaultModule) {

           wr.WriteLine("}} // end of namespace {0}", m.CompileName);

diff --git a/Source/Dafny/Dafny.atg b/Source/Dafny/Dafny.atg
index 4b9e0c27..bfce5122 100644
--- a/Source/Dafny/Dafny.atg
+++ b/Source/Dafny/Dafny.atg
@@ -14,7 +14,7 @@ using System.IO;
 using System.Text;

 COMPILER Dafny

 /*--------------------------------------------------------------------------*/

-static List<ModuleDecl/*!*/> theModules;

+static ModuleDecl theModule;

 static BuiltIns theBuiltIns;

 static Expression/*!*/ dummyExpr = new LiteralExpr(Token.NoToken);

 static FrameExpression/*!*/ dummyFrameExpr = new FrameExpression(dummyExpr, null);

@@ -28,51 +28,51 @@ struct MemberModifiers {
 // helper routine for parsing call statements

 ///<summary>

 /// Parses top-level things (modules, classes, datatypes, class members) from "filename"

-/// and appends them in appropriate form to "modules".

+/// and appends them in appropriate form to "module".

 /// Returns the number of parsing errors encountered.

 /// Note: first initialize the Scanner.

 ///</summary>

-public static int Parse (string/*!*/ filename, List<ModuleDecl/*!*/>/*!*/ modules, BuiltIns builtIns) /* throws System.IO.IOException */ {

+public static int Parse (string/*!*/ filename, ModuleDecl module, BuiltIns builtIns) /* throws System.IO.IOException */ {

   Contract.Requires(filename != null);

-  Contract.Requires(cce.NonNullElements(modules));

+  Contract.Requires(module != null);

   string s;

   if (filename == "stdin.dfy") {

     s = Microsoft.Boogie.ParserHelper.Fill(System.Console.In, new List<string>());

-    return Parse(s, filename, modules, builtIns);

+    return Parse(s, filename, module, builtIns);

   } else {

     using (System.IO.StreamReader reader = new System.IO.StreamReader(filename)) {

       s = Microsoft.Boogie.ParserHelper.Fill(reader, new List<string>());

-      return Parse(s, filename, modules, builtIns);

+      return Parse(s, filename, module, builtIns);

     }

   }

 }

 ///<summary>

 /// Parses top-level things (modules, classes, datatypes, class members)

-/// and appends them in appropriate form to "modules".

+/// and appends them in appropriate form to "module".

 /// Returns the number of parsing errors encountered.

 /// Note: first initialize the Scanner.

 ///</summary>

-public static int Parse (string/*!*/ s, string/*!*/ filename, List<ModuleDecl/*!*/>/*!*/ modules, BuiltIns builtIns) {

+public static int Parse (string/*!*/ s, string/*!*/ filename, ModuleDecl module, BuiltIns builtIns) {

   Contract.Requires(s != null);

   Contract.Requires(filename != null);

-  Contract.Requires(cce.NonNullElements(modules));

+  Contract.Requires(module != null);

   Errors errors = new Errors();

-  return Parse(s, filename, modules, builtIns, errors);

+  return Parse(s, filename, module, builtIns, errors);

 }

 ///<summary>

 /// Parses top-level things (modules, classes, datatypes, class members)

-/// and appends them in appropriate form to "modules".

+/// and appends them in appropriate form to "module".

 /// Returns the number of parsing errors encountered.

 /// Note: first initialize the Scanner with the given Errors sink.

 ///</summary>

-public static int Parse (string/*!*/ s, string/*!*/ filename, List<ModuleDecl/*!*/>/*!*/ modules, BuiltIns builtIns,

+public static int Parse (string/*!*/ s, string/*!*/ filename, ModuleDecl module, BuiltIns builtIns,

                          Errors/*!*/ errors) {

   Contract.Requires(s != null);

   Contract.Requires(filename != null);

-  Contract.Requires(cce.NonNullElements(modules));

+  Contract.Requires(module != null);

   Contract.Requires(errors != null);

-  List<ModuleDecl/*!*/> oldModules = theModules;

-  theModules = modules;

+  var oldModule = theModule;

+  theModule = module;

   BuiltIns oldBuiltIns = builtIns;

   theBuiltIns = builtIns;

   byte[]/*!*/ buffer = cce.NonNull( UTF8Encoding.Default.GetBytes(s));

@@ -80,7 +80,7 @@ public static int Parse (string/*!*/ s, string/*!*/ filename, List<ModuleDecl/*!
   Scanner scanner = new Scanner(ms, errors, filename);

   Parser parser = new Parser(scanner, errors);

   parser.Parse();

-  theModules = oldModules;

+  theModule = oldModule;

   theBuiltIns = oldBuiltIns;

   return parser.errors.count;

 }

@@ -131,43 +131,19 @@ IGNORE cr + lf + tab
 PRODUCTIONS

 Dafny

 = (. ClassDecl/*!*/ c; DatatypeDecl/*!*/ dt; ArbitraryTypeDecl at;

-     Attributes attrs;  IToken/*!*/ id;  List<string/*!*/> theImports;

      List<MemberDecl/*!*/> membersDefaultClass = new List<MemberDecl/*!*/>();

-     List<MemberDecl/*!*/> namedModuleDefaultClassMembers;

-     ModuleDecl module;

-     // to support multiple files, create a default module only if theModules doesn't already contain one

-     DefaultModuleDecl defaultModule = null;

-     foreach (ModuleDecl mdecl in theModules) {

-       defaultModule = mdecl as DefaultModuleDecl;

-       if (defaultModule != null) { break; }

-     }

-     bool defaultModuleCreatedHere = false;

-     if (defaultModule == null) {

-       defaultModuleCreatedHere = true;

-       defaultModule = new DefaultModuleDecl();

-     }

-     IToken idRefined;

+     ModuleDecl submodule;

+     // to support multiple files, create a default module only if theModule is null

+     DefaultModuleDecl defaultModule = (DefaultModuleDecl)((LiteralModuleDecl)theModule).ModuleDef;

+     // theModule should be a DefaultModuleDecl (actually, the singular DefaultModuleDecl)

+     Contract.Assert(defaultModule != null);

      bool isGhost;

   .)

   { (. isGhost = false; .)

     [ "ghost"  (. isGhost = true; .) ]

 

-    ( "module"                             (. attrs = null;  idRefined = null;  theImports = new List<string/*!*/>();

-                                              namedModuleDefaultClassMembers = new List<MemberDecl>();

-                                           .)

-      { Attribute<ref attrs> }

-      Ident<out id>                        (. defaultModule.ImportNames.Add(id.val); .)

-      [ "refines" Ident<out idRefined> ]

-      [ "imports" Idents<theImports> ]     (. module = new ModuleDecl(id, id.val, isGhost, idRefined == null ? null : idRefined.val, theImports, attrs); .)

-      "{"                                  (. module.BodyStartTok = t; .)

-        { ClassDecl<module, out c>         (. module.TopLevelDecls.Add(c); .)

-        | DatatypeDecl<module, out dt>     (. module.TopLevelDecls.Add(dt); .)

-        | ArbitraryTypeDecl<module, out at>(. module.TopLevelDecls.Add(at); .)

-        | ClassMemberDecl<namedModuleDefaultClassMembers, false, false>

-        }

-      "}"                                  (. module.BodyEndTok = t;

-                                              module.TopLevelDecls.Add(new DefaultClassDecl(module, namedModuleDefaultClassMembers));

-                                              theModules.Add(module); .)

+    ( SubModuleDecl<defaultModule, isGhost, out submodule> 

+                                                (. defaultModule.TopLevelDecls.Add(submodule); .)

     | (. if (isGhost) { SemErr(t, "a class is not allowed to be declared as 'ghost'"); } .)

       ClassDecl<defaultModule, out c>           (. defaultModule.TopLevelDecls.Add(c); .)

     | (. if (isGhost) { SemErr(t, "a datatype/codatatype is not allowed to be declared as 'ghost'"); } .)

@@ -177,23 +153,67 @@ Dafny
     | ClassMemberDecl<membersDefaultClass, isGhost, false>

     )

   }

-  (. if (defaultModuleCreatedHere) {

-       defaultModule.TopLevelDecls.Add(new DefaultClassDecl(defaultModule, membersDefaultClass));

-       theModules.Add(defaultModule);

-     } else {

-       // find the default class in the default module, then append membersDefaultClass to its member list

-       foreach (TopLevelDecl topleveldecl in defaultModule.TopLevelDecls) {

-         DefaultClassDecl defaultClass = topleveldecl as DefaultClassDecl;

-         if (defaultClass != null) {

-           defaultClass.Members.AddRange(membersDefaultClass);

-           break;

-         }

+  (. // find the default class in the default module, then append membersDefaultClass to its member list

+     DefaultClassDecl defaultClass = null;

+     foreach (TopLevelDecl topleveldecl in defaultModule.TopLevelDecls) {

+       defaultClass = topleveldecl as DefaultClassDecl;

+       if (defaultClass != null) {

+         defaultClass.Members.AddRange(membersDefaultClass);

+         break;

        }

      }

-  .)

+     if (defaultClass == null) { // create the default class here, because it wasn't found

+       defaultClass = new DefaultClassDecl(defaultModule, membersDefaultClass);

+       defaultModule.TopLevelDecls.Add(defaultClass);

+     } .)

   EOF

   .

-ClassDecl<ModuleDecl/*!*/ module, out ClassDecl/*!*/ c>

+SubModuleDecl<ModuleDefinition parent, bool isOverallModuleGhost, out ModuleDecl submodule>

+= (. ClassDecl/*!*/ c; DatatypeDecl/*!*/ dt; ArbitraryTypeDecl at;

+     Attributes attrs = null;  IToken/*!*/ id; 

+     List<MemberDecl/*!*/> namedModuleDefaultClassMembers = new List<MemberDecl>();;

+     List<IToken> idRefined = null, idPath = null;

+     bool isGhost = false;

+     ModuleDefinition module;

+     ModuleDecl sm;

+     submodule = null; // appease compiler

+  .)

+    "module"

+    { Attribute<ref attrs> }

+    NoUSIdent<out id>                          

+    ((

+      [ "refines" QualifiedName<out idRefined> ] (. module = new ModuleDefinition(id, id.val, isOverallModuleGhost, false, idRefined == null ? null : idRefined, attrs); .)

+       "{"                                       (. module.BodyStartTok = t; .)

+        { (. isGhost = false; .)

+          [ "ghost"  (. isGhost = true; .) ]

+            ( SubModuleDecl<module, isGhost, out sm>        (. module.TopLevelDecls.Add(sm); .)

+            | (. if (isGhost) { SemErr(t, "a class is not allowed to be declared as 'ghost'"); } .)

+              ClassDecl<module, out c>           (. module.TopLevelDecls.Add(c); .)

+            | (. if (isGhost) { SemErr(t, "a datatype/codatatype is not allowed to be declared as 'ghost'"); } .)

+              DatatypeDecl<module, out dt>       (. module.TopLevelDecls.Add(dt); .)

+            | (. if (isGhost) { SemErr(t, "a type is not allowed to be declared as 'ghost'"); } .)

+              ArbitraryTypeDecl<module, out at>  (. module.TopLevelDecls.Add(at); .)

+            | ClassMemberDecl<namedModuleDefaultClassMembers, isGhost, false>

+            )

+        }

+      "}"                                  (. module.BodyEndTok = t;

+                                              module.TopLevelDecls.Add(new DefaultClassDecl(module, namedModuleDefaultClassMembers));

+                                              submodule = new LiteralModuleDecl(module, parent); .)

+     ) | 

+      "=" QualifiedName<out idPath> ";" (. submodule = new AliasModuleDecl(idPath, id, parent); .)

+       |

+      "as" QualifiedName<out idPath> ";" (.submodule = new AbstractModuleDecl(idPath, id, parent); .)

+    )

+.

+

+QualifiedName<.out List<IToken> ids.>

+= (. IToken id; ids = new List<IToken>(); .)

+  Ident<out id>                            (. ids.Add(id); .)

+  { "." Ident<out id>                      (. ids.Add(id); .)

+  }

+  .

+

+ClassDecl<ModuleDefinition/*!*/ module, out ClassDecl/*!*/ c>

 = (. Contract.Requires(module != null);

      Contract.Ensures(Contract.ValueAtReturn(out c) != null);

      IToken/*!*/ id;

@@ -205,7 +225,7 @@ ClassDecl<ModuleDecl/*!*/ module, out ClassDecl/*!*/ c>
   SYNC

   "class"

   { Attribute<ref attrs> }

-  Ident<out id>

+  NoUSIdent<out id>

   [ GenericParameters<typeArgs> ]

   "{"                                            (. bodyStart = t; .)

   { ClassMemberDecl<members, false, true>

@@ -231,7 +251,7 @@ ClassMemberDecl<.List<MemberDecl/*!*/>/*!*/ mm, bool isAlreadyGhost, bool allowC
   | MethodDecl<mmod, allowConstructors, out m>  (. mm.Add(m); .)

   )

   .

-DatatypeDecl<ModuleDecl/*!*/ module, out DatatypeDecl/*!*/ dt>

+DatatypeDecl<ModuleDefinition/*!*/ module, out DatatypeDecl/*!*/ dt>

 = (. Contract.Requires(module != null);

      Contract.Ensures(Contract.ValueAtReturn(out dt)!=null);

      IToken/*!*/ id;

@@ -246,7 +266,7 @@ DatatypeDecl<ModuleDecl/*!*/ module, out DatatypeDecl/*!*/ dt>
   | "codatatype"     (. co = true; .)

   )

   { Attribute<ref attrs> }

-  Ident<out id>

+  NoUSIdent<out id>

   [ GenericParameters<typeArgs> ]

   "="                                      (. bodyStart = t; .)

   DatatypeMemberDecl<ctors>

@@ -268,7 +288,7 @@ DatatypeMemberDecl<.List<DatatypeCtor/*!*/>/*!*/ ctors.>
      List<Formal/*!*/> formals = new List<Formal/*!*/>();

   .)

   { Attribute<ref attrs> }

-  Ident<out id>

+  NoUSIdent<out id>

   [ FormalsOptionalIds<formals> ]

   (. ctors.Add(new DatatypeCtor(id, id.val, formals, attrs)); .)

   .

@@ -287,14 +307,14 @@ FieldDecl<.MemberModifiers mmod, List<MemberDecl/*!*/>/*!*/ mm.>
   }

   SYNC ";"

   .

-ArbitraryTypeDecl<ModuleDecl/*!*/ module, out ArbitraryTypeDecl at>

+ArbitraryTypeDecl<ModuleDefinition/*!*/ module, out ArbitraryTypeDecl at>

 = (. IToken/*!*/ id;

      Attributes attrs = null;

      var eqSupport = TypeParameter.EqualitySupportValue.Unspecified;

   .)

   "type"

   { Attribute<ref attrs> }

-  Ident<out id>

+  NoUSIdent<out id>

   [ "(" "==" ")"               (. eqSupport = TypeParameter.EqualitySupportValue.Required; .)

   ]                            (. at = new ArbitraryTypeDecl(id, id.val, module, eqSupport, attrs); .)

   SYNC ";"

@@ -310,14 +330,14 @@ GIdentType<bool allowGhostKeyword, out IToken/*!*/ id, out Type/*!*/ ty, out boo
   .

 IdentType<out IToken/*!*/ id, out Type/*!*/ ty>

 = (.Contract.Ensures(Contract.ValueAtReturn(out id) != null); Contract.Ensures(Contract.ValueAtReturn(out ty) != null);.)

-  Ident<out id>

+  NoUSIdent<out id>

   ":"

   Type<out ty>

   .

 LocalIdentTypeOptional<out VarDecl/*!*/ var, bool isGhost>

 = (. IToken/*!*/ id;  Type/*!*/ ty;  Type optType = null;

   .)

-  Ident<out id>

+  NoUSIdent<out id>

   [ ":" Type<out ty>             (. optType = ty; .)

   ]

   (. var = new VarDecl(id, id.val, optType == null ? new InferredTypeProxy() : optType, isGhost); .)

@@ -325,7 +345,7 @@ LocalIdentTypeOptional<out VarDecl/*!*/ var, bool isGhost>
 IdentTypeOptional<out BoundVar/*!*/ var>

 = (. Contract.Ensures(Contract.ValueAtReturn(out var)!=null); IToken/*!*/ id;  Type/*!*/ ty;  Type optType = null;

   .)

-  Ident<out id>

+  NoUSIdent<out id>

   [ ":" Type<out ty>             (. optType = ty; .)

   ]

   (. var = new BoundVar(id, id.val, optType == null ? new InferredTypeProxy() : optType); .)

@@ -363,10 +383,10 @@ GenericParameters<.List<TypeParameter/*!*/>/*!*/ typeArgs.>
      TypeParameter.EqualitySupportValue eqSupport;

   .)

   "<"

-  Ident<out id>              (. eqSupport = TypeParameter.EqualitySupportValue.Unspecified; .)

+  NoUSIdent<out id>              (. eqSupport = TypeParameter.EqualitySupportValue.Unspecified; .)

   [ "(" "==" ")"             (. eqSupport = TypeParameter.EqualitySupportValue.Required; .)

     ]                        (. typeArgs.Add(new TypeParameter(id, id.val, eqSupport)); .)

-  { "," Ident<out id>        (. eqSupport = TypeParameter.EqualitySupportValue.Unspecified; .)

+  { "," NoUSIdent<out id>        (. eqSupport = TypeParameter.EqualitySupportValue.Unspecified; .)

     [ "(" "==" ")"           (. eqSupport = TypeParameter.EqualitySupportValue.Required; .)

     ]                        (. typeArgs.Add(new TypeParameter(id, id.val, eqSupport)); .)

   }

@@ -412,7 +432,7 @@ MethodDecl<MemberModifiers mmod, bool allowConstructor, out Method/*!*/ m>
      }

   .)

   { Attribute<ref attrs> }

-  Ident<out id>

+  NoUSIdent<out id>

   (

     [ GenericParameters<typeArgs> ]

     Formals<true, !mmod.IsGhost, ins, out openParen>

@@ -572,7 +592,7 @@ FunctionDecl<MemberModifiers mmod, out Function/*!*/ f>
     (. if (mmod.IsGhost) { SemErr(t, "functions cannot be declared 'ghost' (they are ghost by default)"); }

     .)

     { Attribute<ref attrs> }

-    Ident<out id>

+    NoUSIdent<out id>

     (

       [ GenericParameters<typeArgs> ]

       Formals<true, isFunctionMethod, formals, out openParen>

@@ -589,7 +609,7 @@ FunctionDecl<MemberModifiers mmod, out Function/*!*/ f>
     (. if (mmod.IsGhost) { SemErr(t, "predicates cannot be declared 'ghost' (they are ghost by default)"); }

     .)

     { Attribute<ref attrs> }

-    Ident<out id>

+    NoUSIdent<out id>

     (

       [ GenericParameters<typeArgs> ]

       [ Formals<true, isFunctionMethod, formals, out openParen>

@@ -699,10 +719,10 @@ OneStmt<out Statement/*!*/ s>
   | MatchStmt<out s>

   | ParallelStmt<out s>

   | "label"                            (. x = t; .)

-    Ident<out id> ":"

+    NoUSIdent<out id> ":"

     OneStmt<out s>                     (. s.Labels = new LList<Label>(new Label(x, id.val), s.Labels); .)

   | "break"                            (. x = t; breakCount = 1; label = null; .)

-    ( Ident<out id>                    (. label = id.val; .)

+    ( NoUSIdent<out id>                    (. label = id.val; .)

     | { "break"                        (. breakCount++; .)

       }

     )

@@ -1643,16 +1663,20 @@ AttributeArg<out Attributes.Argument/*!*/ arg>
   )

   .

 /*------------------------------------------------------------------------*/

-Idents<.List<string/*!*/>/*!*/ ids.>

-= (. IToken/*!*/ id; .)

-  Ident<out id>                            (. ids.Add(id.val); .)

-  { "," Ident<out id>                      (. ids.Add(id.val); .)

-  }

-  .

 Ident<out IToken/*!*/ x>

 = (. Contract.Ensures(Contract.ValueAtReturn(out x) != null); .)

   ident            (. x = t; .)

   .

+// Identifier, disallowing leading underscores

+NoUSIdent<out IToken/*!*/ x>

+= (. Contract.Ensures(Contract.ValueAtReturn(out x) != null); .)

+  ident            (. x = t; 

+                      if (x.val.Length > 0 && x.val.StartsWith("_")) {

+                        SemErr("cannot declare identifier beginning with underscore");

+                      }

+                   .)

+  .

+

 Nat<out BigInteger n>

 =

   digits

diff --git a/Source/Dafny/DafnyAst.cs b/Source/Dafny/DafnyAst.cs
index bf985ddc..ee4592ce 100644
--- a/Source/Dafny/DafnyAst.cs
+++ b/Source/Dafny/DafnyAst.cs
@@ -15,30 +15,37 @@ namespace Microsoft.Dafny {
     [ContractInvariantMethod]

     void ObjectInvariant() {

       Contract.Invariant(Name != null);

-      Contract.Invariant(cce.NonNullElements(Modules));

+      Contract.Invariant(DefaultModule != null);

     }

 

     public readonly string Name;

-    public readonly List<ModuleDecl/*!*/>/*!*/ Modules;

+    public List<ModuleDefinition/*!*/>/*!*/ Modules; // filled in during resolution.

+                                               // Resolution essentially flattens the module heirarchy, for

+                                               // purposes of translation and compilation.

+    public readonly ModuleDecl DefaultModule;

+    public readonly ModuleDefinition DefaultModuleDef;

     public readonly BuiltIns BuiltIns;

-    public Program(string name, [Captured] List<ModuleDecl/*!*/>/*!*/ modules, [Captured] BuiltIns builtIns) {

+    public Program(string name, [Captured] ModuleDecl module, [Captured] BuiltIns builtIns) {

       Contract.Requires(name != null);

-      Contract.Requires(cce.NonNullElements(modules));

+      Contract.Requires(module != null);

+      Contract.Requires(module is LiteralModuleDecl);

       Name = name;

-      Modules = modules;

+      DefaultModule = module;

+      DefaultModuleDef = (DefaultModuleDecl)((LiteralModuleDecl)module).ModuleDef;

       BuiltIns = builtIns;

+      Modules = new List<ModuleDefinition>();

     }

   }

 

   public class BuiltIns

   {

-    public readonly ModuleDecl SystemModule = new ModuleDecl(Token.NoToken, "_System", false, null, new List<string>(), null);

+    public readonly ModuleDefinition SystemModule = new ModuleDefinition(Token.NoToken, "_System", false, false, null, null);

     Dictionary<int, ClassDecl/*!*/> arrayTypeDecls = new Dictionary<int, ClassDecl>();

-

+    public readonly ClassDecl ObjectDecl;

     public BuiltIns() {

       // create class 'object'

-      ClassDecl obj = new ClassDecl(Token.NoToken, "object", SystemModule, new List<TypeParameter>(), new List<MemberDecl>(), null);

-      SystemModule.TopLevelDecls.Add(obj);

+      ObjectDecl = new ClassDecl(Token.NoToken, "object", SystemModule, new List<TypeParameter>(), new List<MemberDecl>(), null);

+      SystemModule.TopLevelDecls.Add(ObjectDecl);

       // add one-dimensional arrays, since they may arise during type checking

       UserDefinedType tmp = ArrayType(Token.NoToken, 1, Type.Int, true);

     }

@@ -782,47 +789,120 @@ namespace Microsoft.Dafny {
     }

   }

 

-  public class ModuleDecl : Declaration {

-    public readonly string RefinementBaseName;  // null if no refinement base

-    public ModuleDecl RefinementBase;  // filled in during resolution (null if no refinement base)

-    public readonly List<string/*!*/>/*!*/ ImportNames;  // contains no duplicates

-    public readonly List<ModuleDecl>/*!*/ Imports = new List<ModuleDecl>();  // filled in during resolution, contains no duplicates

+  // Represents a submodule declartion at module level scope

+  abstract public class ModuleDecl : TopLevelDecl

+  {

+    public ModuleSignature Signature; // filled in by resolution, in topological order.

+    public int Height;

+    public ModuleDecl(IToken tok, string name, ModuleDefinition parent)

+      : base(tok, name, parent, new List<TypeParameter>(), null) {

+        Height = -1;

+        Signature = null;

+    }

+  }

+  // Represents module X { ... }

+  public class LiteralModuleDecl : ModuleDecl

+  {

+    public readonly ModuleDefinition ModuleDef;

+    public LiteralModuleDecl(ModuleDefinition module, ModuleDefinition parent)

+      : base(module.tok, module.Name, parent) {

+      ModuleDef = module;

+    }

+  }

+  // Represents "module name = path;", where name is a identifier and path is a possibly qualified name.

+  public class AliasModuleDecl : ModuleDecl

+  {

+    public ModuleDecl ModuleReference; // should refer to another declaration somewhere. NOTE: cyclicity is possible, and should

+                                       // be detected and warned.

+    public readonly List<IToken> Path; // generated by the parser, this is looked up

+    public ModuleDecl Root;            // the moduleDecl that Path[0] refers to.

+    public AliasModuleDecl(List<IToken> path, IToken name, ModuleDefinition parent)

+      : base(name, name.val, parent) {

+       Contract.Requires(path != null && path.Count > 0);

+       Path = path;

+       ModuleReference = null;

+    }

+  }

+  // Represents "module name as path;", where name is a identifier and path is a possibly qualified name.

+  public class AbstractModuleDecl : ModuleDecl

+  {

+    public ModuleDecl Root;

+    public readonly List<IToken> Path;

+    public ModuleSignature OriginalSignature;

+    public AbstractModuleDecl(List<IToken> path, IToken name, ModuleDefinition parent)

+      : base(name, name.val, parent) {

+      Path = path;

+      Root = null;

+    }

+  }

+

+  public class ModuleSignature {

+    

+    public readonly Dictionary<string, TopLevelDecl> TopLevels = new Dictionary<string, TopLevelDecl>();

+    public readonly Dictionary<string, Tuple<DatatypeCtor, bool>> Ctors = new Dictionary<string, Tuple<DatatypeCtor, bool>>();

+    public ModuleDefinition ModuleDef; // Note: this is null if this signature does not correspond to a specific definition (i.e.

+                                       // it is abstract). Otherwise, it points to that definition.

+    public ModuleSignature Refines;

+    public ModuleSignature() {}

+

+    public bool FindSubmodule(string name, out ModuleSignature pp) {

+      TopLevelDecl top;

+      pp = null;

+      if (TopLevels.TryGetValue(name, out top)) {

+        if (top is ModuleDecl) {

+          pp = ((ModuleDecl)top).Signature;

+          return true;

+        } else return false;

+      } else return false;

+    }

+    

+      

+  }

+  public class ModuleDefinition : Declaration {

+    public readonly List<IToken> RefinementBaseName;  // null if no refinement base

+    public ModuleDecl RefinementBaseRoot; // filled in early during resolution, corresponds to RefinementBaseName[0]

+    public ModuleDefinition RefinementBase;  // filled in during resolution (null if no refinement base)

+    

     public readonly List<TopLevelDecl/*!*/> TopLevelDecls = new List<TopLevelDecl/*!*/>();  // filled in by the parser; readonly after that

     public readonly Graph<MemberDecl/*!*/> CallGraph = new Graph<MemberDecl/*!*/>();  // filled in during resolution

     public int Height;  // height in the topological sorting of modules; filled in during resolution

     public readonly bool IsGhost;

+    public readonly bool IsAbstract; // True iff this module represents an abstract interface

 

     [ContractInvariantMethod]

     void ObjectInvariant() {

-      Contract.Invariant(cce.NonNullElements(ImportNames));

       Contract.Invariant(cce.NonNullElements(TopLevelDecls));

       Contract.Invariant(CallGraph != null);

     }

 

-    public ModuleDecl(IToken tok, string name, bool isGhost, string refinementBase, [Captured] List<string/*!*/>/*!*/ imports, Attributes attributes)

+    public ModuleDefinition(IToken tok, string name, bool isGhost, bool isAbstract, List<IToken> refinementBase,  Attributes attributes)

       : base(tok, name, attributes) {

       Contract.Requires(tok != null);

       Contract.Requires(name != null);

-      Contract.Requires(cce.NonNullElements(imports));

       RefinementBaseName = refinementBase;

-      // set "ImportNames" to "imports" minus any duplicates

-      ImportNames = new List<string>();

-      foreach (var nm in imports) {

-        if (!ImportNames.Contains(nm)) {

-          ImportNames.Add(nm);

-        }

-      }

       IsGhost = isGhost;

+      IsAbstract = isAbstract;

+      RefinementBaseRoot = null;

+      RefinementBase = null;

     }

     public virtual bool IsDefaultModule {

       get {

         return false;

       }

     }

+    string compileName;

+    new public string CompileName {

+      get {

+        if (compileName == null) {

+          compileName = "_" + Height.ToString() + "_" + NonglobalVariable.CompilerizeName(Name);

+        }

+        return compileName;

+      }

+    }

   }

 

-  public class DefaultModuleDecl : ModuleDecl {

-    public DefaultModuleDecl() : base(Token.NoToken, "_default", false, null, new List<string/*!*/>(), null) {

+  public class DefaultModuleDecl : ModuleDefinition {

+    public DefaultModuleDecl() : base(Token.NoToken, "_module", false, false, null, null) {

     }

     public override bool IsDefaultModule {

       get {

@@ -832,19 +912,17 @@ namespace Microsoft.Dafny {
   }

 

   public abstract class TopLevelDecl : Declaration, TypeParameter.ParentType {

-    public readonly ModuleDecl Module;

+    public readonly ModuleDefinition Module;

     public readonly List<TypeParameter/*!*/>/*!*/ TypeArgs;

     [ContractInvariantMethod]

     void ObjectInvariant() {

-      Contract.Invariant(Module != null);

       Contract.Invariant(cce.NonNullElements(TypeArgs));

     }

 

-    public TopLevelDecl(IToken/*!*/ tok, string/*!*/ name, ModuleDecl/*!*/ module, List<TypeParameter/*!*/>/*!*/ typeArgs, Attributes attributes)

+    public TopLevelDecl(IToken/*!*/ tok, string/*!*/ name, ModuleDefinition module, List<TypeParameter/*!*/>/*!*/ typeArgs, Attributes attributes)

       : base(tok, name, attributes) {

       Contract.Requires(tok != null);

       Contract.Requires(name != null);

-      Contract.Requires(module != null);

       Contract.Requires(cce.NonNullElements(typeArgs));

       Module = module;

       TypeArgs = typeArgs;

@@ -870,7 +948,7 @@ namespace Microsoft.Dafny {
       Contract.Invariant(cce.NonNullElements(Members));

     }

 

-    public ClassDecl(IToken/*!*/ tok, string/*!*/ name, ModuleDecl/*!*/ module,

+    public ClassDecl(IToken/*!*/ tok, string/*!*/ name, ModuleDefinition/*!*/ module,

       List<TypeParameter/*!*/>/*!*/ typeArgs, [Captured] List<MemberDecl/*!*/>/*!*/ members, Attributes attributes)

       : base(tok, name, module, typeArgs, attributes) {

       Contract.Requires(tok != null);

@@ -890,7 +968,7 @@ namespace Microsoft.Dafny {
   }

 

   public class DefaultClassDecl : ClassDecl {

-    public DefaultClassDecl(ModuleDecl/*!*/ module, [Captured] List<MemberDecl/*!*/>/*!*/ members)

+    public DefaultClassDecl(ModuleDefinition/*!*/ module, [Captured] List<MemberDecl/*!*/>/*!*/ members)

       : base(Token.NoToken, "_default", module, new List<TypeParameter/*!*/>(), members, null) {

       Contract.Requires(module != null);

       Contract.Requires(cce.NonNullElements(members));

@@ -904,7 +982,7 @@ namespace Microsoft.Dafny {
 

   public class ArrayClassDecl : ClassDecl {

     public readonly int Dims;

-    public ArrayClassDecl(int dims, ModuleDecl module)

+    public ArrayClassDecl(int dims, ModuleDefinition module)

     : base(Token.NoToken, BuiltIns.ArrayClassName(dims), module,

       new List<TypeParameter>(new TypeParameter[]{new TypeParameter(Token.NoToken, "arg")}),

       new List<MemberDecl>(), null)

@@ -924,7 +1002,7 @@ namespace Microsoft.Dafny {
       Contract.Invariant(1 <= Ctors.Count);

     }

 

-    public DatatypeDecl(IToken/*!*/ tok, string/*!*/ name, ModuleDecl/*!*/ module, List<TypeParameter/*!*/>/*!*/ typeArgs,

+    public DatatypeDecl(IToken/*!*/ tok, string/*!*/ name, ModuleDefinition/*!*/ module, List<TypeParameter/*!*/>/*!*/ typeArgs,

       [Captured] List<DatatypeCtor/*!*/>/*!*/ ctors, Attributes attributes)

       : base(tok, name, module, typeArgs, attributes) {

       Contract.Requires(tok != null);

@@ -945,7 +1023,7 @@ namespace Microsoft.Dafny {
     public enum ES { NotYetComputed, Never, ConsultTypeArguments }

     public ES EqualitySupport = ES.NotYetComputed;

 

-    public IndDatatypeDecl(IToken/*!*/ tok, string/*!*/ name, ModuleDecl/*!*/ module, List<TypeParameter/*!*/>/*!*/ typeArgs,

+    public IndDatatypeDecl(IToken/*!*/ tok, string/*!*/ name, ModuleDefinition/*!*/ module, List<TypeParameter/*!*/>/*!*/ typeArgs,

       [Captured] List<DatatypeCtor/*!*/>/*!*/ ctors, Attributes attributes)

       : base(tok, name, module, typeArgs, ctors, attributes) {

       Contract.Requires(tok != null);

@@ -959,7 +1037,7 @@ namespace Microsoft.Dafny {
 

   public class CoDatatypeDecl : DatatypeDecl

   {

-    public CoDatatypeDecl(IToken/*!*/ tok, string/*!*/ name, ModuleDecl/*!*/ module, List<TypeParameter/*!*/>/*!*/ typeArgs,

+    public CoDatatypeDecl(IToken/*!*/ tok, string/*!*/ name, ModuleDefinition/*!*/ module, List<TypeParameter/*!*/>/*!*/ typeArgs,

       [Captured] List<DatatypeCtor/*!*/>/*!*/ ctors, Attributes attributes)

       : base(tok, name, module, typeArgs, ctors, attributes) {

       Contract.Requires(tok != null);

@@ -1109,7 +1187,7 @@ namespace Microsoft.Dafny {
       Contract.Invariant(TheType != null && Name == TheType.Name);

     }

 

-    public ArbitraryTypeDecl(IToken/*!*/ tok, string/*!*/ name, ModuleDecl/*!*/ module, TypeParameter.EqualitySupportValue equalitySupport, Attributes attributes)

+    public ArbitraryTypeDecl(IToken/*!*/ tok, string/*!*/ name, ModuleDefinition/*!*/ module, TypeParameter.EqualitySupportValue equalitySupport, Attributes attributes)

       : base(tok, name, module, new List<TypeParameter>(), attributes) {

       Contract.Requires(tok != null);

       Contract.Requires(name != null);

diff --git a/Source/Dafny/DafnyMain.cs b/Source/Dafny/DafnyMain.cs
index 62facb31..6091e522 100644
--- a/Source/Dafny/DafnyMain.cs
+++ b/Source/Dafny/DafnyMain.cs
@@ -20,7 +20,7 @@ namespace Microsoft.Dafny {
       Contract.Requires(programName != null);

       Contract.Requires(fileNames != null);

       program = null;

-      List<ModuleDecl> modules = new List<ModuleDecl>();

+      ModuleDecl module = new LiteralModuleDecl(new DefaultModuleDecl(), null);

       BuiltIns builtIns = new BuiltIns();

       foreach (string dafnyFileName in fileNames){

         Contract.Assert(dafnyFileName != null);

@@ -35,7 +35,7 @@ namespace Microsoft.Dafny {
         int errorCount;

         try

         {

-          errorCount = Dafny.Parser.Parse(dafnyFileName, modules, builtIns);

+          errorCount = Dafny.Parser.Parse(dafnyFileName, module, builtIns);

           if (errorCount != 0)

           {

             return string.Format("{0} parse errors detected in {1}", errorCount, dafnyFileName);

@@ -47,7 +47,7 @@ namespace Microsoft.Dafny {
         }

       }

 

-      program = new Program(programName, modules, builtIns);

+      program = new Program(programName, module, builtIns);

 

       if (DafnyOptions.O.DafnyPrintFile != null) {

         string filename = DafnyOptions.O.DafnyPrintFile;

diff --git a/Source/Dafny/DafnyPipeline.csproj b/Source/Dafny/DafnyPipeline.csproj
index cf2b51eb..14ff3348 100644
--- a/Source/Dafny/DafnyPipeline.csproj
+++ b/Source/Dafny/DafnyPipeline.csproj
@@ -151,6 +151,7 @@
     <Reference Include="System.Xml" />

   </ItemGroup>

   <ItemGroup>

+    <Compile Include="Util.cs" />

     <Compile Include="Compiler.cs" />

     <Compile Include="DafnyAst.cs" />

     <Compile Include="DafnyMain.cs" />

diff --git a/Source/Dafny/Parser.cs b/Source/Dafny/Parser.cs
index a4e51924..9ad05d3b 100644
--- a/Source/Dafny/Parser.cs
+++ b/Source/Dafny/Parser.cs
@@ -34,7 +34,7 @@ public class Parser {
 	public Token/*!*/ la;   // lookahead token

 	int errDist = minErrDist;

 

-static List<ModuleDecl/*!*/> theModules;

+static ModuleDecl theModule;

 static BuiltIns theBuiltIns;

 static Expression/*!*/ dummyExpr = new LiteralExpr(Token.NoToken);

 static FrameExpression/*!*/ dummyFrameExpr = new FrameExpression(dummyExpr, null);

@@ -48,51 +48,51 @@ struct MemberModifiers {
 // helper routine for parsing call statements

 ///<summary>

 /// Parses top-level things (modules, classes, datatypes, class members) from "filename"

-/// and appends them in appropriate form to "modules".

+/// and appends them in appropriate form to "module".

 /// Returns the number of parsing errors encountered.

 /// Note: first initialize the Scanner.

 ///</summary>

-public static int Parse (string/*!*/ filename, List<ModuleDecl/*!*/>/*!*/ modules, BuiltIns builtIns) /* throws System.IO.IOException */ {

+public static int Parse (string/*!*/ filename, ModuleDecl module, BuiltIns builtIns) /* throws System.IO.IOException */ {

   Contract.Requires(filename != null);

-  Contract.Requires(cce.NonNullElements(modules));

+  Contract.Requires(module != null);

   string s;

   if (filename == "stdin.dfy") {

     s = Microsoft.Boogie.ParserHelper.Fill(System.Console.In, new List<string>());

-    return Parse(s, filename, modules, builtIns);

+    return Parse(s, filename, module, builtIns);

   } else {

     using (System.IO.StreamReader reader = new System.IO.StreamReader(filename)) {

       s = Microsoft.Boogie.ParserHelper.Fill(reader, new List<string>());

-      return Parse(s, filename, modules, builtIns);

+      return Parse(s, filename, module, builtIns);

     }

   }

 }

 ///<summary>

 /// Parses top-level things (modules, classes, datatypes, class members)

-/// and appends them in appropriate form to "modules".

+/// and appends them in appropriate form to "module".

 /// Returns the number of parsing errors encountered.

 /// Note: first initialize the Scanner.

 ///</summary>

-public static int Parse (string/*!*/ s, string/*!*/ filename, List<ModuleDecl/*!*/>/*!*/ modules, BuiltIns builtIns) {

+public static int Parse (string/*!*/ s, string/*!*/ filename, ModuleDecl module, BuiltIns builtIns) {

   Contract.Requires(s != null);

   Contract.Requires(filename != null);

-  Contract.Requires(cce.NonNullElements(modules));

+  Contract.Requires(module != null);

   Errors errors = new Errors();

-  return Parse(s, filename, modules, builtIns, errors);

+  return Parse(s, filename, module, builtIns, errors);

 }

 ///<summary>

 /// Parses top-level things (modules, classes, datatypes, class members)

-/// and appends them in appropriate form to "modules".

+/// and appends them in appropriate form to "module".

 /// Returns the number of parsing errors encountered.

 /// Note: first initialize the Scanner with the given Errors sink.

 ///</summary>

-public static int Parse (string/*!*/ s, string/*!*/ filename, List<ModuleDecl/*!*/>/*!*/ modules, BuiltIns builtIns,

+public static int Parse (string/*!*/ s, string/*!*/ filename, ModuleDecl module, BuiltIns builtIns,

                          Errors/*!*/ errors) {

   Contract.Requires(s != null);

   Contract.Requires(filename != null);

-  Contract.Requires(cce.NonNullElements(modules));

+  Contract.Requires(module != null);

   Contract.Requires(errors != null);

-  List<ModuleDecl/*!*/> oldModules = theModules;

-  theModules = modules;

+  var oldModule = theModule;

+  theModule = module;

   BuiltIns oldBuiltIns = builtIns;

   theBuiltIns = builtIns;

   byte[]/*!*/ buffer = cce.NonNull( UTF8Encoding.Default.GetBytes(s));

@@ -100,7 +100,7 @@ public static int Parse (string/*!*/ s, string/*!*/ filename, List<ModuleDecl/*!
   Scanner scanner = new Scanner(ms, errors, filename);

   Parser parser = new Parser(scanner, errors);

   parser.Parse();

-  theModules = oldModules;

+  theModule = oldModule;

   theBuiltIns = oldBuiltIns;

   return parser.errors.count;

 }

@@ -181,22 +181,12 @@ bool IsAttribute() {
 

 	void Dafny() {

 		ClassDecl/*!*/ c; DatatypeDecl/*!*/ dt; ArbitraryTypeDecl at;

-		Attributes attrs;  IToken/*!*/ id;  List<string/*!*/> theImports;

 		List<MemberDecl/*!*/> membersDefaultClass = new List<MemberDecl/*!*/>();

-		List<MemberDecl/*!*/> namedModuleDefaultClassMembers;

-		ModuleDecl module;

-		// to support multiple files, create a default module only if theModules doesn't already contain one

-		DefaultModuleDecl defaultModule = null;

-		foreach (ModuleDecl mdecl in theModules) {

-		 defaultModule = mdecl as DefaultModuleDecl;

-		 if (defaultModule != null) { break; }

-		}

-		bool defaultModuleCreatedHere = false;

-		if (defaultModule == null) {

-		 defaultModuleCreatedHere = true;

-		 defaultModule = new DefaultModuleDecl();

-		}

-		IToken idRefined;

+		ModuleDecl submodule;

+		// to support multiple files, create a default module only if theModule is null

+		DefaultModuleDecl defaultModule = (DefaultModuleDecl)((LiteralModuleDecl)theModule).ModuleDef;

+		// theModule should be a DefaultModuleDecl (actually, the singular DefaultModuleDecl)

+		Contract.Assert(defaultModule != null);

 		bool isGhost;

 		

 		while (StartOf(1)) {

@@ -206,101 +196,105 @@ bool IsAttribute() {
 				isGhost = true; 

 			}

 			if (la.kind == 9) {

-				Get();

-				attrs = null;  idRefined = null;  theImports = new List<string/*!*/>();

-				namedModuleDefaultClassMembers = new List<MemberDecl>();

-				

-				while (la.kind == 6) {

-					Attribute(ref attrs);

-				}

-				Ident(out id);

-				defaultModule.ImportNames.Add(id.val); 

-				if (la.kind == 10) {

-					Get();

-					Ident(out idRefined);

-				}

-				if (la.kind == 11) {

-					Get();

-					Idents(theImports);

-				}

-				module = new ModuleDecl(id, id.val, isGhost, idRefined == null ? null : idRefined.val, theImports, attrs); 

-				Expect(6);

-				module.BodyStartTok = t; 

-				while (StartOf(2)) {

-					if (la.kind == 12) {

-						ClassDecl(module, out c);

-						module.TopLevelDecls.Add(c); 

-					} else if (la.kind == 14 || la.kind == 15) {

-						DatatypeDecl(module, out dt);

-						module.TopLevelDecls.Add(dt); 

-					} else if (la.kind == 21) {

-						ArbitraryTypeDecl(module, out at);

-						module.TopLevelDecls.Add(at); 

-					} else {

-						ClassMemberDecl(namedModuleDefaultClassMembers, false, false);

-					}

-				}

-				Expect(7);

-				module.BodyEndTok = t;

-				module.TopLevelDecls.Add(new DefaultClassDecl(module, namedModuleDefaultClassMembers));

-				theModules.Add(module); 

-			} else if (la.kind == 12) {

+				SubModuleDecl(defaultModule, isGhost, out submodule);

+				defaultModule.TopLevelDecls.Add(submodule); 

+			} else if (la.kind == 15) {

 				if (isGhost) { SemErr(t, "a class is not allowed to be declared as 'ghost'"); } 

 				ClassDecl(defaultModule, out c);

 				defaultModule.TopLevelDecls.Add(c); 

-			} else if (la.kind == 14 || la.kind == 15) {

+			} else if (la.kind == 17 || la.kind == 18) {

 				if (isGhost) { SemErr(t, "a datatype/codatatype is not allowed to be declared as 'ghost'"); } 

 				DatatypeDecl(defaultModule, out dt);

 				defaultModule.TopLevelDecls.Add(dt); 

-			} else if (la.kind == 21) {

+			} else if (la.kind == 22) {

 				if (isGhost) { SemErr(t, "a type is not allowed to be declared as 'ghost'"); } 

 				ArbitraryTypeDecl(defaultModule, out at);

 				defaultModule.TopLevelDecls.Add(at); 

-			} else if (StartOf(3)) {

+			} else if (StartOf(2)) {

 				ClassMemberDecl(membersDefaultClass, isGhost, false);

 			} else SynErr(108);

 		}

-		if (defaultModuleCreatedHere) {

-		 defaultModule.TopLevelDecls.Add(new DefaultClassDecl(defaultModule, membersDefaultClass));

-		 theModules.Add(defaultModule);

-		} else {

-		 // find the default class in the default module, then append membersDefaultClass to its member list

-		 foreach (TopLevelDecl topleveldecl in defaultModule.TopLevelDecls) {

-		   DefaultClassDecl defaultClass = topleveldecl as DefaultClassDecl;

-		   if (defaultClass != null) {

-		     defaultClass.Members.AddRange(membersDefaultClass);

-		     break;

-		   }

+		DefaultClassDecl defaultClass = null;

+		foreach (TopLevelDecl topleveldecl in defaultModule.TopLevelDecls) {

+		 defaultClass = topleveldecl as DefaultClassDecl;

+		 if (defaultClass != null) {

+		   defaultClass.Members.AddRange(membersDefaultClass);

+		   break;

 		 }

 		}

-		

+		if (defaultClass == null) { // create the default class here, because it wasn't found

+		 defaultClass = new DefaultClassDecl(defaultModule, membersDefaultClass);

+		 defaultModule.TopLevelDecls.Add(defaultClass);

+		} 

 		Expect(0);

 	}

 

-	void Attribute(ref Attributes attrs) {

-		Expect(6);

-		AttributeBody(ref attrs);

-		Expect(7);

-	}

-

-	void Ident(out IToken/*!*/ x) {

-		Contract.Ensures(Contract.ValueAtReturn(out x) != null); 

-		Expect(1);

-		x = t; 

-	}

-

-	void Idents(List<string/*!*/>/*!*/ ids) {

-		IToken/*!*/ id; 

-		Ident(out id);

-		ids.Add(id.val); 

-		while (la.kind == 20) {

-			Get();

-			Ident(out id);

-			ids.Add(id.val); 

+	void SubModuleDecl(ModuleDefinition parent, bool isOverallModuleGhost, out ModuleDecl submodule) {

+		ClassDecl/*!*/ c; DatatypeDecl/*!*/ dt; ArbitraryTypeDecl at;

+		Attributes attrs = null;  IToken/*!*/ id; 

+		List<MemberDecl/*!*/> namedModuleDefaultClassMembers = new List<MemberDecl>();;

+		List<IToken> idRefined = null, idPath = null;

+		bool isGhost = false;

+		ModuleDefinition module;

+		ModuleDecl sm;

+		submodule = null; // appease compiler

+		

+		Expect(9);

+		while (la.kind == 6) {

+			Attribute(ref attrs);

 		}

+		NoUSIdent(out id);

+		if (la.kind == 6 || la.kind == 10) {

+			if (la.kind == 10) {

+				Get();

+				QualifiedName(out idRefined);

+			}

+			module = new ModuleDefinition(id, id.val, isOverallModuleGhost, false, idRefined == null ? null : idRefined, attrs); 

+			Expect(6);

+			module.BodyStartTok = t; 

+			while (StartOf(1)) {

+				isGhost = false; 

+				if (la.kind == 8) {

+					Get();

+					isGhost = true; 

+				}

+				if (la.kind == 9) {

+					SubModuleDecl(module, isGhost, out sm);

+					module.TopLevelDecls.Add(sm); 

+				} else if (la.kind == 15) {

+					if (isGhost) { SemErr(t, "a class is not allowed to be declared as 'ghost'"); } 

+					ClassDecl(module, out c);

+					module.TopLevelDecls.Add(c); 

+				} else if (la.kind == 17 || la.kind == 18) {

+					if (isGhost) { SemErr(t, "a datatype/codatatype is not allowed to be declared as 'ghost'"); } 

+					DatatypeDecl(module, out dt);

+					module.TopLevelDecls.Add(dt); 

+				} else if (la.kind == 22) {

+					if (isGhost) { SemErr(t, "a type is not allowed to be declared as 'ghost'"); } 

+					ArbitraryTypeDecl(module, out at);

+					module.TopLevelDecls.Add(at); 

+				} else if (StartOf(2)) {

+					ClassMemberDecl(namedModuleDefaultClassMembers, isGhost, false);

+				} else SynErr(109);

+			}

+			Expect(7);

+			module.BodyEndTok = t;

+			module.TopLevelDecls.Add(new DefaultClassDecl(module, namedModuleDefaultClassMembers));

+			submodule = new LiteralModuleDecl(module, parent); 

+		} else if (la.kind == 11) {

+			Get();

+			QualifiedName(out idPath);

+			Expect(12);

+			submodule = new AliasModuleDecl(idPath, id, parent); 

+		} else if (la.kind == 13) {

+			Get();

+			QualifiedName(out idPath);

+			Expect(12);

+			submodule = new AbstractModuleDecl(idPath, id, parent); 

+		} else SynErr(110);

 	}

 

-	void ClassDecl(ModuleDecl/*!*/ module, out ClassDecl/*!*/ c) {

+	void ClassDecl(ModuleDefinition/*!*/ module, out ClassDecl/*!*/ c) {

 		Contract.Requires(module != null);

 		Contract.Ensures(Contract.ValueAtReturn(out c) != null);

 		IToken/*!*/ id;

@@ -309,18 +303,18 @@ bool IsAttribute() {
 		List<MemberDecl/*!*/> members = new List<MemberDecl/*!*/>();

 		IToken bodyStart;

 		

-		while (!(la.kind == 0 || la.kind == 12)) {SynErr(109); Get();}

-		Expect(12);

+		while (!(la.kind == 0 || la.kind == 15)) {SynErr(111); Get();}

+		Expect(15);

 		while (la.kind == 6) {

 			Attribute(ref attrs);

 		}

-		Ident(out id);

-		if (la.kind == 25) {

+		NoUSIdent(out id);

+		if (la.kind == 26) {

 			GenericParameters(typeArgs);

 		}

 		Expect(6);

 		bodyStart = t; 

-		while (StartOf(3)) {

+		while (StartOf(2)) {

 			ClassMemberDecl(members, false, true);

 		}

 		Expect(7);

@@ -330,7 +324,7 @@ bool IsAttribute() {
 		

 	}

 

-	void DatatypeDecl(ModuleDecl/*!*/ module, out DatatypeDecl/*!*/ dt) {

+	void DatatypeDecl(ModuleDefinition/*!*/ module, out DatatypeDecl/*!*/ dt) {

 		Contract.Requires(module != null);

 		Contract.Ensures(Contract.ValueAtReturn(out dt)!=null);

 		IToken/*!*/ id;

@@ -340,29 +334,29 @@ bool IsAttribute() {
 		IToken bodyStart = Token.NoToken;  // dummy assignment

 		bool co = false;

 		

-		while (!(la.kind == 0 || la.kind == 14 || la.kind == 15)) {SynErr(110); Get();}

-		if (la.kind == 14) {

+		while (!(la.kind == 0 || la.kind == 17 || la.kind == 18)) {SynErr(112); Get();}

+		if (la.kind == 17) {

 			Get();

-		} else if (la.kind == 15) {

+		} else if (la.kind == 18) {

 			Get();

 			co = true; 

-		} else SynErr(111);

+		} else SynErr(113);

 		while (la.kind == 6) {

 			Attribute(ref attrs);

 		}

-		Ident(out id);

-		if (la.kind == 25) {

+		NoUSIdent(out id);

+		if (la.kind == 26) {

 			GenericParameters(typeArgs);

 		}

-		Expect(16);

+		Expect(11);

 		bodyStart = t; 

 		DatatypeMemberDecl(ctors);

-		while (la.kind == 17) {

+		while (la.kind == 19) {

 			Get();

 			DatatypeMemberDecl(ctors);

 		}

-		while (!(la.kind == 0 || la.kind == 18)) {SynErr(112); Get();}

-		Expect(18);

+		while (!(la.kind == 0 || la.kind == 12)) {SynErr(114); Get();}

+		Expect(12);

 		if (co) {

 		 dt = new CoDatatypeDecl(id, id.val, module, typeArgs, ctors, attrs);

 		} else {

@@ -373,25 +367,25 @@ bool IsAttribute() {
 		

 	}

 

-	void ArbitraryTypeDecl(ModuleDecl/*!*/ module, out ArbitraryTypeDecl at) {

+	void ArbitraryTypeDecl(ModuleDefinition/*!*/ module, out ArbitraryTypeDecl at) {

 		IToken/*!*/ id;

 		Attributes attrs = null;

 		var eqSupport = TypeParameter.EqualitySupportValue.Unspecified;

 		

-		Expect(21);

+		Expect(22);

 		while (la.kind == 6) {

 			Attribute(ref attrs);

 		}

-		Ident(out id);

-		if (la.kind == 22) {

+		NoUSIdent(out id);

+		if (la.kind == 23) {

 			Get();

-			Expect(23);

 			Expect(24);

+			Expect(25);

 			eqSupport = TypeParameter.EqualitySupportValue.Required; 

 		}

 		at = new ArbitraryTypeDecl(id, id.val, module, eqSupport, attrs); 

-		while (!(la.kind == 0 || la.kind == 18)) {SynErr(113); Get();}

-		Expect(18);

+		while (!(la.kind == 0 || la.kind == 12)) {SynErr(115); Get();}

+		Expect(12);

 	}

 

 	void ClassMemberDecl(List<MemberDecl/*!*/>/*!*/ mm, bool isAlreadyGhost, bool allowConstructors) {

@@ -401,7 +395,7 @@ bool IsAttribute() {
 		MemberModifiers mmod = new MemberModifiers();

 		mmod.IsGhost = isAlreadyGhost;

 		

-		while (la.kind == 8 || la.kind == 13) {

+		while (la.kind == 8 || la.kind == 16) {

 			if (la.kind == 8) {

 				Get();

 				mmod.IsGhost = true; 

@@ -410,15 +404,48 @@ bool IsAttribute() {
 				mmod.IsStatic = true; 

 			}

 		}

-		if (la.kind == 19) {

+		if (la.kind == 20) {

 			FieldDecl(mmod, mm);

 		} else if (la.kind == 45 || la.kind == 46) {

 			FunctionDecl(mmod, out f);

 			mm.Add(f); 

-		} else if (la.kind == 27 || la.kind == 28) {

+		} else if (la.kind == 28 || la.kind == 29) {

 			MethodDecl(mmod, allowConstructors, out m);

 			mm.Add(m); 

-		} else SynErr(114);

+		} else SynErr(116);

+	}

+

+	void Attribute(ref Attributes attrs) {

+		Expect(6);

+		AttributeBody(ref attrs);

+		Expect(7);

+	}

+

+	void NoUSIdent(out IToken/*!*/ x) {

+		Contract.Ensures(Contract.ValueAtReturn(out x) != null); 

+		Expect(1);

+		x = t; 

+		if (x.val.Length > 0 && x.val.StartsWith("_")) {

+		 SemErr("cannot declare identifier beginning with underscore");

+		}

+		

+	}

+

+	void QualifiedName(out List<IToken> ids) {

+		IToken id; ids = new List<IToken>(); 

+		Ident(out id);

+		ids.Add(id); 

+		while (la.kind == 14) {

+			Get();

+			Ident(out id);

+			ids.Add(id); 

+		}

+	}

+

+	void Ident(out IToken/*!*/ x) {

+		Contract.Ensures(Contract.ValueAtReturn(out x) != null); 

+		Expect(1);

+		x = t; 

 	}

 

 	void GenericParameters(List<TypeParameter/*!*/>/*!*/ typeArgs) {

@@ -426,29 +453,29 @@ bool IsAttribute() {
 		IToken/*!*/ id;

 		TypeParameter.EqualitySupportValue eqSupport;

 		

-		Expect(25);

-		Ident(out id);

+		Expect(26);

+		NoUSIdent(out id);

 		eqSupport = TypeParameter.EqualitySupportValue.Unspecified; 

-		if (la.kind == 22) {

+		if (la.kind == 23) {

 			Get();

-			Expect(23);

 			Expect(24);

+			Expect(25);

 			eqSupport = TypeParameter.EqualitySupportValue.Required; 

 		}

 		typeArgs.Add(new TypeParameter(id, id.val, eqSupport)); 

-		while (la.kind == 20) {

+		while (la.kind == 21) {

 			Get();

-			Ident(out id);

+			NoUSIdent(out id);

 			eqSupport = TypeParameter.EqualitySupportValue.Unspecified; 

-			if (la.kind == 22) {

+			if (la.kind == 23) {

 				Get();

-				Expect(23);

 				Expect(24);

+				Expect(25);

 				eqSupport = TypeParameter.EqualitySupportValue.Required; 

 			}

 			typeArgs.Add(new TypeParameter(id, id.val, eqSupport)); 

 		}

-		Expect(26);

+		Expect(27);

 	}

 

 	void FieldDecl(MemberModifiers mmod, List<MemberDecl/*!*/>/*!*/ mm) {

@@ -456,8 +483,8 @@ bool IsAttribute() {
 		Attributes attrs = null;

 		IToken/*!*/ id;  Type/*!*/ ty;

 		

-		while (!(la.kind == 0 || la.kind == 19)) {SynErr(115); Get();}

-		Expect(19);

+		while (!(la.kind == 0 || la.kind == 20)) {SynErr(117); Get();}

+		Expect(20);

 		if (mmod.IsStatic) { SemErr(t, "fields cannot be declared 'static'"); }

 		

 		while (la.kind == 6) {

@@ -465,13 +492,13 @@ bool IsAttribute() {
 		}

 		IdentType(out id, out ty);

 		mm.Add(new Field(id, id.val, mmod.IsGhost, ty, attrs)); 

-		while (la.kind == 20) {

+		while (la.kind == 21) {

 			Get();

 			IdentType(out id, out ty);

 			mm.Add(new Field(id, id.val, mmod.IsGhost, ty, attrs)); 

 		}

-		while (!(la.kind == 0 || la.kind == 18)) {SynErr(116); Get();}

-		Expect(18);

+		while (!(la.kind == 0 || la.kind == 12)) {SynErr(118); Get();}

+		Expect(12);

 	}

 

 	void FunctionDecl(MemberModifiers mmod, out Function/*!*/ f) {

@@ -495,7 +522,7 @@ bool IsAttribute() {
 		

 		if (la.kind == 45) {

 			Get();

-			if (la.kind == 27) {

+			if (la.kind == 28) {

 				Get();

 				isFunctionMethod = true; 

 			}

@@ -504,23 +531,23 @@ bool IsAttribute() {
 			while (la.kind == 6) {

 				Attribute(ref attrs);

 			}

-			Ident(out id);

-			if (la.kind == 22 || la.kind == 25) {

-				if (la.kind == 25) {

+			NoUSIdent(out id);

+			if (la.kind == 23 || la.kind == 26) {

+				if (la.kind == 26) {

 					GenericParameters(typeArgs);

 				}

 				Formals(true, isFunctionMethod, formals, out openParen);

 				Expect(5);

 				Type(out returnType);

-			} else if (la.kind == 30) {

+			} else if (la.kind == 31) {

 				Get();

 				signatureOmitted = true;

 				openParen = Token.NoToken; 

-			} else SynErr(117);

+			} else SynErr(119);

 		} else if (la.kind == 46) {

 			Get();

 			isPredicate = true; 

-			if (la.kind == 27) {

+			if (la.kind == 28) {

 				Get();

 				isFunctionMethod = true; 

 			}

@@ -529,25 +556,25 @@ bool IsAttribute() {
 			while (la.kind == 6) {

 				Attribute(ref attrs);

 			}

-			Ident(out id);

-			if (StartOf(4)) {

-				if (la.kind == 25) {

+			NoUSIdent(out id);

+			if (StartOf(3)) {

+				if (la.kind == 26) {

 					GenericParameters(typeArgs);

 				}

-				if (la.kind == 22) {

+				if (la.kind == 23) {

 					Formals(true, isFunctionMethod, formals, out openParen);

 					if (la.kind == 5) {

 						Get();

 						SemErr(t, "predicates do not have an explicitly declared return type; it is always bool"); 

 					}

 				}

-			} else if (la.kind == 30) {

+			} else if (la.kind == 31) {

 				Get();

 				signatureOmitted = true;

 				openParen = Token.NoToken; 

-			} else SynErr(118);

-		} else SynErr(119);

-		while (StartOf(5)) {

+			} else SynErr(120);

+		} else SynErr(121);

+		while (StartOf(4)) {

 			FunctionSpec(reqs, reads, ens, decreases);

 		}

 		if (la.kind == 6) {

@@ -585,10 +612,10 @@ bool IsAttribute() {
 		IToken bodyStart = Token.NoToken;

 		IToken bodyEnd = Token.NoToken;

 		

-		while (!(la.kind == 0 || la.kind == 27 || la.kind == 28)) {SynErr(120); Get();}

-		if (la.kind == 27) {

+		while (!(la.kind == 0 || la.kind == 28 || la.kind == 29)) {SynErr(122); Get();}

+		if (la.kind == 28) {

 			Get();

-		} else if (la.kind == 28) {

+		} else if (la.kind == 29) {

 			Get();

 			if (allowConstructor) {

 			 isConstructor = true;

@@ -596,7 +623,7 @@ bool IsAttribute() {
 			 SemErr(t, "constructors are only allowed in classes");

 			}

 			

-		} else SynErr(121);

+		} else SynErr(123);

 		if (isConstructor) {

 		 if (mmod.IsGhost) {

 		   SemErr(t, "constructors cannot be declared 'ghost'");

@@ -609,22 +636,22 @@ bool IsAttribute() {
 		while (la.kind == 6) {

 			Attribute(ref attrs);

 		}

-		Ident(out id);

-		if (la.kind == 22 || la.kind == 25) {

-			if (la.kind == 25) {

+		NoUSIdent(out id);

+		if (la.kind == 23 || la.kind == 26) {

+			if (la.kind == 26) {

 				GenericParameters(typeArgs);

 			}

 			Formals(true, !mmod.IsGhost, ins, out openParen);

-			if (la.kind == 29) {

+			if (la.kind == 30) {

 				Get();

 				if (isConstructor) { SemErr(t, "constructors cannot have out-parameters"); } 

 				Formals(false, !mmod.IsGhost, outs, out openParen);

 			}

-		} else if (la.kind == 30) {

+		} else if (la.kind == 31) {

 			Get();

 			signatureOmitted = true; openParen = Token.NoToken; 

-		} else SynErr(122);

-		while (StartOf(6)) {

+		} else SynErr(124);

+		while (StartOf(5)) {

 			MethodSpec(req, mod, ens, dec, ref decAttrs, ref modAttrs);

 		}

 		if (la.kind == 6) {

@@ -651,8 +678,8 @@ bool IsAttribute() {
 		while (la.kind == 6) {

 			Attribute(ref attrs);

 		}

-		Ident(out id);

-		if (la.kind == 22) {

+		NoUSIdent(out id);

+		if (la.kind == 23) {

 			FormalsOptionalIds(formals);

 		}

 		ctors.Add(new DatatypeCtor(id, id.val, formals, attrs)); 

@@ -660,22 +687,22 @@ bool IsAttribute() {
 

 	void FormalsOptionalIds(List<Formal/*!*/>/*!*/ formals) {

 		Contract.Requires(cce.NonNullElements(formals)); IToken/*!*/ id;  Type/*!*/ ty;  string/*!*/ name;  bool isGhost; 

-		Expect(22);

-		if (StartOf(7)) {

+		Expect(23);

+		if (StartOf(6)) {

 			TypeIdentOptional(out id, out name, out ty, out isGhost);

 			formals.Add(new Formal(id, name, ty, true, isGhost)); 

-			while (la.kind == 20) {

+			while (la.kind == 21) {

 				Get();

 				TypeIdentOptional(out id, out name, out ty, out isGhost);

 				formals.Add(new Formal(id, name, ty, true, isGhost)); 

 			}

 		}

-		Expect(24);

+		Expect(25);

 	}

 

 	void IdentType(out IToken/*!*/ id, out Type/*!*/ ty) {

 		Contract.Ensures(Contract.ValueAtReturn(out id) != null); Contract.Ensures(Contract.ValueAtReturn(out ty) != null);

-		Ident(out id);

+		NoUSIdent(out id);

 		Expect(5);

 		Type(out ty);

 	}

@@ -699,7 +726,7 @@ bool IsAttribute() {
 	void LocalIdentTypeOptional(out VarDecl/*!*/ var, bool isGhost) {

 		IToken/*!*/ id;  Type/*!*/ ty;  Type optType = null;

 		

-		Ident(out id);

+		NoUSIdent(out id);

 		if (la.kind == 5) {

 			Get();

 			Type(out ty);

@@ -711,7 +738,7 @@ bool IsAttribute() {
 	void IdentTypeOptional(out BoundVar/*!*/ var) {

 		Contract.Ensures(Contract.ValueAtReturn(out var)!=null); IToken/*!*/ id;  Type/*!*/ ty;  Type optType = null;

 		

-		Ident(out id);

+		NoUSIdent(out id);

 		if (la.kind == 5) {

 			Get();

 			Type(out ty);

@@ -754,22 +781,22 @@ bool IsAttribute() {
 		List<Type/*!*/>/*!*/ gt;

 		

 		switch (la.kind) {

-		case 36: {

+		case 37: {

 			Get();

 			tok = t; 

 			break;

 		}

-		case 37: {

+		case 38: {

 			Get();

 			tok = t;  ty = new NatType(); 

 			break;

 		}

-		case 38: {

+		case 39: {

 			Get();

 			tok = t;  ty = new IntType(); 

 			break;

 		}

-		case 39: {

+		case 40: {

 			Get();

 			tok = t;  gt = new List<Type/*!*/>(); 

 			GenericInstantiation(gt);

@@ -780,7 +807,7 @@ bool IsAttribute() {
 			

 			break;

 		}

-		case 40: {

+		case 41: {

 			Get();

 			tok = t;  gt = new List<Type/*!*/>(); 

 			GenericInstantiation(gt);

@@ -791,7 +818,7 @@ bool IsAttribute() {
 			

 			break;

 		}

-		case 41: {

+		case 42: {

 			Get();

 			tok = t;  gt = new List<Type/*!*/>(); 

 			GenericInstantiation(gt);

@@ -802,7 +829,7 @@ bool IsAttribute() {
 			

 			break;

 		}

-		case 42: {

+		case 43: {

 			Get();

 			tok = t;  gt = new List<Type/*!*/>(); 

 			GenericInstantiation(gt);

@@ -813,28 +840,28 @@ bool IsAttribute() {
 			

 			break;

 		}

-		case 1: case 3: case 43: {

+		case 1: case 3: case 44: {

 			ReferenceType(out tok, out ty);

 			break;

 		}

-		default: SynErr(123); break;

+		default: SynErr(125); break;

 		}

 	}

 

 	void Formals(bool incoming, bool allowGhostKeyword, List<Formal/*!*/>/*!*/ formals, out IToken openParen) {

 		Contract.Requires(cce.NonNullElements(formals)); IToken/*!*/ id;  Type/*!*/ ty;  bool isGhost; 

-		Expect(22);

+		Expect(23);

 		openParen = t; 

 		if (la.kind == 1 || la.kind == 8) {

 			GIdentType(allowGhostKeyword, out id, out ty, out isGhost);

 			formals.Add(new Formal(id, id.val, ty, incoming, isGhost)); 

-			while (la.kind == 20) {

+			while (la.kind == 21) {

 				Get();

 				GIdentType(allowGhostKeyword, out id, out ty, out isGhost);

 				formals.Add(new Formal(id, id.val, ty, incoming, isGhost)); 

 			}

 		}

-		Expect(24);

+		Expect(25);

 	}

 

 	void MethodSpec(List<MaybeFreeExpression/*!*/>/*!*/ req, List<FrameExpression/*!*/>/*!*/ mod, List<MaybeFreeExpression/*!*/>/*!*/ ens,

@@ -842,53 +869,53 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		Contract.Requires(cce.NonNullElements(req)); Contract.Requires(cce.NonNullElements(mod)); Contract.Requires(cce.NonNullElements(ens)); Contract.Requires(cce.NonNullElements(decreases));

 		Expression/*!*/ e;  FrameExpression/*!*/ fe;  bool isFree = false; Attributes ensAttrs = null;

 		

-		while (!(StartOf(8))) {SynErr(124); Get();}

-		if (la.kind == 31) {

+		while (!(StartOf(7))) {SynErr(126); Get();}

+		if (la.kind == 32) {

 			Get();

 			while (IsAttribute()) {

 				Attribute(ref modAttrs);

 			}

-			if (StartOf(9)) {

+			if (StartOf(8)) {

 				FrameExpression(out fe);

 				mod.Add(fe); 

-				while (la.kind == 20) {

+				while (la.kind == 21) {

 					Get();

 					FrameExpression(out fe);

 					mod.Add(fe); 

 				}

 			}

-			while (!(la.kind == 0 || la.kind == 18)) {SynErr(125); Get();}

-			Expect(18);

-		} else if (la.kind == 32 || la.kind == 33 || la.kind == 34) {

-			if (la.kind == 32) {

+			while (!(la.kind == 0 || la.kind == 12)) {SynErr(127); Get();}

+			Expect(12);

+		} else if (la.kind == 33 || la.kind == 34 || la.kind == 35) {

+			if (la.kind == 33) {

 				Get();

 				isFree = true; 

 			}

-			if (la.kind == 33) {

+			if (la.kind == 34) {

 				Get();

 				Expression(out e);

-				while (!(la.kind == 0 || la.kind == 18)) {SynErr(126); Get();}

-				Expect(18);

+				while (!(la.kind == 0 || la.kind == 12)) {SynErr(128); Get();}

+				Expect(12);

 				req.Add(new MaybeFreeExpression(e, isFree)); 

-			} else if (la.kind == 34) {

+			} else if (la.kind == 35) {

 				Get();

 				while (IsAttribute()) {

 					Attribute(ref ensAttrs);

 				}

 				Expression(out e);

-				while (!(la.kind == 0 || la.kind == 18)) {SynErr(127); Get();}

-				Expect(18);

+				while (!(la.kind == 0 || la.kind == 12)) {SynErr(129); Get();}

+				Expect(12);

 				ens.Add(new MaybeFreeExpression(e, isFree, ensAttrs)); 

-			} else SynErr(128);

-		} else if (la.kind == 35) {

+			} else SynErr(130);

+		} else if (la.kind == 36) {

 			Get();

 			while (IsAttribute()) {

 				Attribute(ref decAttrs);

 			}

 			DecreasesList(decreases, false);

-			while (!(la.kind == 0 || la.kind == 18)) {SynErr(129); Get();}

-			Expect(18);

-		} else SynErr(130);

+			while (!(la.kind == 0 || la.kind == 12)) {SynErr(131); Get();}

+			Expect(12);

+		} else SynErr(132);

 	}

 

 	void BlockStmt(out BlockStmt/*!*/ block, out IToken bodyStart, out IToken bodyEnd) {

@@ -897,7 +924,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		

 		Expect(6);

 		bodyStart = t; 

-		while (StartOf(10)) {

+		while (StartOf(9)) {

 			Stmt(body);

 		}

 		Expect(7);

@@ -929,7 +956,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		 decreases.Add(e);

 		}

 		

-		while (la.kind == 20) {

+		while (la.kind == 21) {

 			Get();

 			PossiblyWildExpression(out e);

 			if (!allowWildcard && e is WildcardExpr) {

@@ -943,15 +970,15 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 

 	void GenericInstantiation(List<Type/*!*/>/*!*/ gt) {

 		Contract.Requires(cce.NonNullElements(gt)); Type/*!*/ ty; 

-		Expect(25);

+		Expect(26);

 		Type(out ty);

 		gt.Add(ty); 

-		while (la.kind == 20) {

+		while (la.kind == 21) {

 			Get();

 			Type(out ty);

 			gt.Add(ty); 

 		}

-		Expect(26);

+		Expect(27);

 	}

 

 	void ReferenceType(out IToken/*!*/ tok, out Type/*!*/ ty) {

@@ -960,7 +987,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		IToken moduleName = null;

 		List<Type/*!*/>/*!*/ gt;

 		

-		if (la.kind == 43) {

+		if (la.kind == 44) {

 			Get();

 			tok = t;  ty = new ObjectType(); 

 		} else if (la.kind == 3) {

@@ -979,53 +1006,53 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		} else if (la.kind == 1) {

 			Ident(out tok);

 			gt = new List<Type/*!*/>(); 

-			if (la.kind == 44) {

+			if (la.kind == 14) {

 				moduleName = tok; 

 				Get();

 				Ident(out tok);

 			}

-			if (la.kind == 25) {

+			if (la.kind == 26) {

 				GenericInstantiation(gt);

 			}

 			ty = new UserDefinedType(tok, tok.val, gt, moduleName); 

-		} else SynErr(131);

+		} else SynErr(133);

 	}

 

 	void FunctionSpec(List<Expression/*!*/>/*!*/ reqs, List<FrameExpression/*!*/>/*!*/ reads, List<Expression/*!*/>/*!*/ ens, List<Expression/*!*/>/*!*/ decreases) {

 		Contract.Requires(cce.NonNullElements(reqs)); Contract.Requires(cce.NonNullElements(reads)); Contract.Requires(cce.NonNullElements(decreases));

 		Expression/*!*/ e;  FrameExpression/*!*/ fe; 

-		if (la.kind == 33) {

-			while (!(la.kind == 0 || la.kind == 33)) {SynErr(132); Get();}

+		if (la.kind == 34) {

+			while (!(la.kind == 0 || la.kind == 34)) {SynErr(134); Get();}

 			Get();

 			Expression(out e);

-			while (!(la.kind == 0 || la.kind == 18)) {SynErr(133); Get();}

-			Expect(18);

+			while (!(la.kind == 0 || la.kind == 12)) {SynErr(135); Get();}

+			Expect(12);

 			reqs.Add(e); 

 		} else if (la.kind == 47) {

 			Get();

-			if (StartOf(11)) {

+			if (StartOf(10)) {

 				PossiblyWildFrameExpression(out fe);

 				reads.Add(fe); 

-				while (la.kind == 20) {

+				while (la.kind == 21) {

 					Get();

 					PossiblyWildFrameExpression(out fe);

 					reads.Add(fe); 

 				}

 			}

-			while (!(la.kind == 0 || la.kind == 18)) {SynErr(134); Get();}

-			Expect(18);

-		} else if (la.kind == 34) {

+			while (!(la.kind == 0 || la.kind == 12)) {SynErr(136); Get();}

+			Expect(12);

+		} else if (la.kind == 35) {

 			Get();

 			Expression(out e);

-			while (!(la.kind == 0 || la.kind == 18)) {SynErr(135); Get();}

-			Expect(18);

+			while (!(la.kind == 0 || la.kind == 12)) {SynErr(137); Get();}

+			Expect(12);

 			ens.Add(e); 

-		} else if (la.kind == 35) {

+		} else if (la.kind == 36) {

 			Get();

 			DecreasesList(decreases, false);

-			while (!(la.kind == 0 || la.kind == 18)) {SynErr(136); Get();}

-			Expect(18);

-		} else SynErr(137);

+			while (!(la.kind == 0 || la.kind == 12)) {SynErr(138); Get();}

+			Expect(12);

+		} else SynErr(139);

 	}

 

 	void FunctionBody(out Expression/*!*/ e, out IToken bodyStart, out IToken bodyEnd) {

@@ -1042,9 +1069,9 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		if (la.kind == 48) {

 			Get();

 			fe = new FrameExpression(new WildcardExpr(t), null); 

-		} else if (StartOf(9)) {

+		} else if (StartOf(8)) {

 			FrameExpression(out fe);

-		} else SynErr(138);

+		} else SynErr(140);

 	}

 

 	void PossiblyWildExpression(out Expression/*!*/ e) {

@@ -1053,9 +1080,9 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		if (la.kind == 48) {

 			Get();

 			e = new WildcardExpr(t); 

-		} else if (StartOf(9)) {

+		} else if (StartOf(8)) {

 			Expression(out e);

-		} else SynErr(139);

+		} else SynErr(141);

 	}

 

 	void Stmt(List<Statement/*!*/>/*!*/ ss) {

@@ -1072,7 +1099,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		IToken bodyStart, bodyEnd;

 		int breakCount;

 		

-		while (!(StartOf(12))) {SynErr(140); Get();}

+		while (!(StartOf(11))) {SynErr(142); Get();}

 		switch (la.kind) {

 		case 6: {

 			BlockStmt(out bs, out bodyStart, out bodyEnd);

@@ -1091,11 +1118,11 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 			PrintStmt(out s);

 			break;

 		}

-		case 1: case 2: case 17: case 22: case 92: case 93: case 94: case 95: case 96: case 97: case 98: {

+		case 1: case 2: case 19: case 23: case 92: case 93: case 94: case 95: case 96: case 97: case 98: {

 			UpdateStmt(out s);

 			break;

 		}

-		case 8: case 19: {

+		case 8: case 20: {

 			VarDeclStatement(out s);

 			break;

 		}

@@ -1118,7 +1145,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		case 50: {

 			Get();

 			x = t; 

-			Ident(out id);

+			NoUSIdent(out id);

 			Expect(5);

 			OneStmt(out s);

 			s.Labels = new LList<Label>(new Label(x, id.val), s.Labels); 

@@ -1128,16 +1155,16 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 			Get();

 			x = t; breakCount = 1; label = null; 

 			if (la.kind == 1) {

-				Ident(out id);

+				NoUSIdent(out id);

 				label = id.val; 

-			} else if (la.kind == 18 || la.kind == 51) {

+			} else if (la.kind == 12 || la.kind == 51) {

 				while (la.kind == 51) {

 					Get();

 					breakCount++; 

 				}

-			} else SynErr(141);

-			while (!(la.kind == 0 || la.kind == 18)) {SynErr(142); Get();}

-			Expect(18);

+			} else SynErr(143);

+			while (!(la.kind == 0 || la.kind == 12)) {SynErr(144); Get();}

+			Expect(12);

 			s = label != null ? new BreakStmt(x, label) : new BreakStmt(x, breakCount); 

 			break;

 		}

@@ -1145,13 +1172,13 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 			ReturnStmt(out s);

 			break;

 		}

-		case 30: {

+		case 31: {

 			Get();

 			s = new SkeletonStatement(t); 

-			Expect(18);

+			Expect(12);

 			break;

 		}

-		default: SynErr(143); break;

+		default: SynErr(145); break;

 		}

 	}

 

@@ -1164,12 +1191,12 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		while (IsAttribute()) {

 			Attribute(ref attrs);

 		}

-		if (StartOf(9)) {

+		if (StartOf(8)) {

 			Expression(out e);

-		} else if (la.kind == 30) {

+		} else if (la.kind == 31) {

 			Get();

-		} else SynErr(144);

-		Expect(18);

+		} else SynErr(146);

+		Expect(12);

 		if (e == null) {

 		 s = new SkeletonStatement(new AssertStmt(x, new LiteralExpr(x, true), attrs), true, false);

 		} else {

@@ -1187,18 +1214,18 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		while (IsAttribute()) {

 			Attribute(ref attrs);

 		}

-		if (StartOf(9)) {

+		if (StartOf(8)) {

 			Expression(out e);

-		} else if (la.kind == 30) {

+		} else if (la.kind == 31) {

 			Get();

-		} else SynErr(145);

+		} else SynErr(147);

 		if (e == null) {

 		 s = new SkeletonStatement(new AssumeStmt(x, new LiteralExpr(x, true), attrs), true, false);

 		} else {

 		 s = new AssumeStmt(x, e, attrs);

 		}

 		

-		Expect(18);

+		Expect(12);

 	}

 

 	void PrintStmt(out Statement/*!*/ s) {

@@ -1209,12 +1236,12 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		x = t; 

 		AttributeArg(out arg);

 		args.Add(arg); 

-		while (la.kind == 20) {

+		while (la.kind == 21) {

 			Get();

 			AttributeArg(out arg);

 			args.Add(arg); 

 		}

-		Expect(18);

+		Expect(12);

 		s = new PrintStmt(x, args); 

 	}

 

@@ -1230,15 +1257,15 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		

 		Lhs(out e);

 		x = e.tok; 

-		if (la.kind == 6 || la.kind == 18) {

+		if (la.kind == 6 || la.kind == 12) {

 			while (la.kind == 6) {

 				Attribute(ref attrs);

 			}

-			Expect(18);

+			Expect(12);

 			rhss.Add(new ExprRhs(e, attrs)); 

-		} else if (la.kind == 20 || la.kind == 53 || la.kind == 54) {

+		} else if (la.kind == 21 || la.kind == 53 || la.kind == 54) {

 			lhss.Add(e);  lhs0 = e; 

-			while (la.kind == 20) {

+			while (la.kind == 21) {

 				Get();

 				Lhs(out e);

 				lhss.Add(e); 

@@ -1248,7 +1275,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 				x = t; 

 				Rhs(out r, lhs0);

 				rhss.Add(r); 

-				while (la.kind == 20) {

+				while (la.kind == 21) {

 					Get();

 					Rhs(out r, lhs0);

 					rhss.Add(r); 

@@ -1261,12 +1288,12 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 					suchThatAssume = t; 

 				}

 				Expression(out suchThat);

-			} else SynErr(146);

-			Expect(18);

+			} else SynErr(148);

+			Expect(12);

 		} else if (la.kind == 5) {

 			Get();

 			SemErr(t, "invalid statement (did you forget the 'label' keyword?)"); 

-		} else SynErr(147);

+		} else SynErr(149);

 		if (suchThat != null) {

 		 s = new AssignSuchThatStmt(x, lhss, suchThat, suchThatAssume);

 		} else {

@@ -1288,11 +1315,11 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 			Get();

 			isGhost = true;  x = t; 

 		}

-		Expect(19);

+		Expect(20);

 		if (!isGhost) { x = t; } 

 		LocalIdentTypeOptional(out d, isGhost);

 		lhss.Add(d); 

-		while (la.kind == 20) {

+		while (la.kind == 21) {

 			Get();

 			LocalIdentTypeOptional(out d, isGhost);

 			lhss.Add(d); 

@@ -1306,7 +1333,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 				

 				Rhs(out r, lhs0);

 				rhss.Add(r); 

-				while (la.kind == 20) {

+				while (la.kind == 21) {

 					Get();

 					Rhs(out r, lhs0);

 					rhss.Add(r); 

@@ -1321,7 +1348,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 				Expression(out suchThat);

 			}

 		}

-		Expect(18);

+		Expect(12);

 		ConcreteUpdateStatement update;

 		if (suchThat != null) {

 		 var ies = new List<Expression>();

@@ -1355,8 +1382,8 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		

 		Expect(60);

 		x = t; 

-		if (la.kind == 22 || la.kind == 30) {

-			if (la.kind == 22) {

+		if (la.kind == 23 || la.kind == 31) {

+			if (la.kind == 23) {

 				Guard(out guard);

 			} else {

 				Get();

@@ -1371,7 +1398,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 				} else if (la.kind == 6) {

 					BlockStmt(out bs, out bodyStart, out bodyEnd);

 					els = bs; 

-				} else SynErr(148);

+				} else SynErr(150);

 			}

 			if (guardOmitted) {

 			 ifStmt = new SkeletonStatement(new IfStmt(x, guard, thn, els), true, false);

@@ -1382,7 +1409,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		} else if (la.kind == 6) {

 			AlternativeBlock(out alternatives);

 			ifStmt = new AlternativeStmt(x, alternatives); 

-		} else SynErr(149);

+		} else SynErr(151);

 	}

 

 	void WhileStmt(out Statement/*!*/ stmt) {

@@ -1400,8 +1427,8 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		

 		Expect(64);

 		x = t; 

-		if (la.kind == 22 || la.kind == 30) {

-			if (la.kind == 22) {

+		if (la.kind == 23 || la.kind == 31) {

+			if (la.kind == 23) {

 				Guard(out guard);

 				Contract.Assume(guard == null || cce.Owner.None(guard)); 

 			} else {

@@ -1411,10 +1438,10 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 			LoopSpec(out invariants, out decreases, out mod, ref decAttrs, ref modAttrs);

 			if (la.kind == 6) {

 				BlockStmt(out body, out bodyStart, out bodyEnd);

-			} else if (la.kind == 30) {

+			} else if (la.kind == 31) {

 				Get();

 				bodyOmitted = true; 

-			} else SynErr(150);

+			} else SynErr(152);

 			if (guardOmitted || bodyOmitted) {

 			 if (mod != null) {

 			   SemErr(mod[0].E.tok, "'modifies' clauses are not allowed on refining loops");

@@ -1428,11 +1455,11 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 			 stmt = new WhileStmt(x, guard, invariants, new Specification<Expression>(decreases, decAttrs), new Specification<FrameExpression>(mod, modAttrs), body);

 			}

 			

-		} else if (StartOf(13)) {

+		} else if (StartOf(12)) {

 			LoopSpec(out invariants, out decreases, out mod, ref decAttrs, ref modAttrs);

 			AlternativeBlock(out alternatives);

 			stmt = new AlternativeLoopStmt(x, invariants, new Specification<Expression>(decreases, decAttrs), new Specification<FrameExpression>(mod, modAttrs), alternatives); 

-		} else SynErr(151);

+		} else SynErr(153);

 	}

 

 	void MatchStmt(out Statement/*!*/ s) {

@@ -1465,7 +1492,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		

 		Expect(69);

 		x = t; 

-		Expect(22);

+		Expect(23);

 		if (la.kind == 1) {

 			List<BoundVar/*!*/> bvarsX;  Attributes attrsX;  Expression rangeX; 

 			QuantifierDomain(out bvarsX, out attrsX, out rangeX);

@@ -1475,16 +1502,16 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		if (bvars == null) { bvars = new List<BoundVar>(); }

 		if (range == null) { range = new LiteralExpr(x, true); }

 		

-		Expect(24);

-		while (la.kind == 32 || la.kind == 34) {

+		Expect(25);

+		while (la.kind == 33 || la.kind == 35) {

 			isFree = false; 

-			if (la.kind == 32) {

+			if (la.kind == 33) {

 				Get();

 				isFree = true; 

 			}

-			Expect(34);

+			Expect(35);

 			Expression(out e);

-			Expect(18);

+			Expect(12);

 			ens.Add(new MaybeFreeExpression(e, isFree)); 

 		}

 		BlockStmt(out block, out bodyStart, out bodyEnd);

@@ -1498,16 +1525,16 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		

 		Expect(52);

 		returnTok = t; 

-		if (StartOf(14)) {

+		if (StartOf(13)) {

 			Rhs(out r, null);

 			rhss = new List<AssignmentRhs>(); rhss.Add(r); 

-			while (la.kind == 20) {

+			while (la.kind == 21) {

 				Get();

 				Rhs(out r, null);

 				rhss.Add(r); 

 			}

 		}

-		Expect(18);

+		Expect(12);

 		s = new ReturnStmt(returnTok, rhss); 

 	}

 

@@ -1524,7 +1551,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 			Get();

 			newToken = t; 

 			TypeAndToken(out x, out ty);

-			if (la.kind == 22 || la.kind == 44 || la.kind == 57) {

+			if (la.kind == 14 || la.kind == 23 || la.kind == 57) {

 				if (la.kind == 57) {

 					Get();

 					ee = new List<Expression>(); 

@@ -1532,15 +1559,15 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 					Expect(58);

 					UserDefinedType tmp = theBuiltIns.ArrayType(x, ee.Count, new IntType(), true);

 					

-				} else if (la.kind == 44) {

+				} else if (la.kind == 14) {

 					Get();

 					Ident(out x);

-					Expect(22);

+					Expect(23);

 					args = new List<Expression/*!*/>(); 

-					if (StartOf(9)) {

+					if (StartOf(8)) {

 						Expressions(args);

 					}

-					Expect(24);

+					Expect(25);

 					initCall = new CallStmt(x, new List<Expression>(), receiverForInitCall, x.val, args); 

 				} else {

 					Get();

@@ -1555,10 +1582,10 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 					 x = null;

 					}

 					args = new List<Expression/*!*/>(); 

-					if (StartOf(9)) {

+					if (StartOf(8)) {

 						Expressions(args);

 					}

-					Expect(24);

+					Expect(25);

 					if (x != null) {

 					 initCall = new CallStmt(x, new List<Expression>(), receiverForInitCall, x.val, args);

 					}

@@ -1579,10 +1606,10 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		} else if (la.kind == 48) {

 			Get();

 			r = new HavocRhs(t); 

-		} else if (StartOf(9)) {

+		} else if (StartOf(8)) {

 			Expression(out e);

 			r = new ExprRhs(e); 

-		} else SynErr(152);

+		} else SynErr(154);

 		while (la.kind == 6) {

 			Attribute(ref attrs);

 		}

@@ -1594,23 +1621,23 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		

 		if (la.kind == 1) {

 			DottedIdentifiersAndFunction(out e);

-			while (la.kind == 44 || la.kind == 57) {

+			while (la.kind == 14 || la.kind == 57) {

 				Suffix(ref e);

 			}

-		} else if (StartOf(15)) {

+		} else if (StartOf(14)) {

 			ConstAtomExpression(out e);

 			Suffix(ref e);

-			while (la.kind == 44 || la.kind == 57) {

+			while (la.kind == 14 || la.kind == 57) {

 				Suffix(ref e);

 			}

-		} else SynErr(153);

+		} else SynErr(155);

 	}

 

 	void Expressions(List<Expression/*!*/>/*!*/ args) {

 		Contract.Requires(cce.NonNullElements(args)); Expression/*!*/ e; 

 		Expression(out e);

 		args.Add(e); 

-		while (la.kind == 20) {

+		while (la.kind == 21) {

 			Get();

 			Expression(out e);

 			args.Add(e); 

@@ -1619,15 +1646,15 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 

 	void Guard(out Expression e) {

 		Expression/*!*/ ee;  e = null; 

-		Expect(22);

+		Expect(23);

 		if (la.kind == 48) {

 			Get();

 			e = null; 

-		} else if (StartOf(9)) {

+		} else if (StartOf(8)) {

 			Expression(out ee);

 			e = ee; 

-		} else SynErr(154);

-		Expect(24);

+		} else SynErr(156);

+		Expect(25);

 	}

 

 	void AlternativeBlock(out List<GuardedAlternative> alternatives) {

@@ -1643,7 +1670,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 			Expression(out e);

 			Expect(63);

 			body = new List<Statement>(); 

-			while (StartOf(10)) {

+			while (StartOf(9)) {

 				Stmt(body);

 			}

 			alternatives.Add(new GuardedAlternative(x, e, body)); 

@@ -1658,47 +1685,47 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		decreases = new List<Expression/*!*/>();

 		mod = null;

 		

-		while (StartOf(16)) {

-			if (la.kind == 32 || la.kind == 65) {

+		while (StartOf(15)) {

+			if (la.kind == 33 || la.kind == 65) {

 				Invariant(out invariant);

-				while (!(la.kind == 0 || la.kind == 18)) {SynErr(155); Get();}

-				Expect(18);

+				while (!(la.kind == 0 || la.kind == 12)) {SynErr(157); Get();}

+				Expect(12);

 				invariants.Add(invariant); 

-			} else if (la.kind == 35) {

-				while (!(la.kind == 0 || la.kind == 35)) {SynErr(156); Get();}

+			} else if (la.kind == 36) {

+				while (!(la.kind == 0 || la.kind == 36)) {SynErr(158); Get();}

 				Get();

 				while (IsAttribute()) {

 					Attribute(ref decAttrs);

 				}

 				DecreasesList(decreases, true);

-				while (!(la.kind == 0 || la.kind == 18)) {SynErr(157); Get();}

-				Expect(18);

+				while (!(la.kind == 0 || la.kind == 12)) {SynErr(159); Get();}

+				Expect(12);

 			} else {

-				while (!(la.kind == 0 || la.kind == 31)) {SynErr(158); Get();}

+				while (!(la.kind == 0 || la.kind == 32)) {SynErr(160); Get();}

 				Get();

 				while (IsAttribute()) {

 					Attribute(ref modAttrs);

 				}

 				mod = mod ?? new List<FrameExpression>(); 

-				if (StartOf(9)) {

+				if (StartOf(8)) {

 					FrameExpression(out fe);

 					mod.Add(fe); 

-					while (la.kind == 20) {

+					while (la.kind == 21) {

 						Get();

 						FrameExpression(out fe);

 						mod.Add(fe); 

 					}

 				}

-				while (!(la.kind == 0 || la.kind == 18)) {SynErr(159); Get();}

-				Expect(18);

+				while (!(la.kind == 0 || la.kind == 12)) {SynErr(161); Get();}

+				Expect(12);

 			}

 		}

 	}

 

 	void Invariant(out MaybeFreeExpression/*!*/ invariant) {

 		bool isFree = false; Expression/*!*/ e; List<string> ids = new List<string>(); invariant = null; Attributes attrs = null; 

-		while (!(la.kind == 0 || la.kind == 32 || la.kind == 65)) {SynErr(160); Get();}

-		if (la.kind == 32) {

+		while (!(la.kind == 0 || la.kind == 33 || la.kind == 65)) {SynErr(162); Get();}

+		if (la.kind == 33) {

 			Get();

 			isFree = true; 

 		}

@@ -1720,19 +1747,19 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		Expect(62);

 		x = t; 

 		Ident(out id);

-		if (la.kind == 22) {

+		if (la.kind == 23) {

 			Get();

 			IdentTypeOptional(out bv);

 			arguments.Add(bv); 

-			while (la.kind == 20) {

+			while (la.kind == 21) {

 				Get();

 				IdentTypeOptional(out bv);

 				arguments.Add(bv); 

 			}

-			Expect(24);

+			Expect(25);

 		}

 		Expect(63);

-		while (StartOf(10)) {

+		while (StartOf(9)) {

 			Stmt(body);

 		}

 		c = new MatchCaseStmt(x, id.val, arguments, body); 

@@ -1743,10 +1770,10 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		if (la.kind == 4) {

 			Get();

 			arg = new Attributes.Argument(t, t.val.Substring(1, t.val.Length-2)); 

-		} else if (StartOf(9)) {

+		} else if (StartOf(8)) {

 			Expression(out e);

 			arg = new Attributes.Argument(t, e); 

-		} else SynErr(161);

+		} else SynErr(163);

 	}

 

 	void QuantifierDomain(out List<BoundVar/*!*/> bvars, out Attributes attrs, out Expression range) {

@@ -1757,7 +1784,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		

 		IdentTypeOptional(out bv);

 		bvars.Add(bv); 

-		while (la.kind == 20) {

+		while (la.kind == 21) {

 			Get();

 			IdentTypeOptional(out bv);

 			bvars.Add(bv); 

@@ -1765,7 +1792,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		while (la.kind == 6) {

 			Attribute(ref attrs);

 		}

-		if (la.kind == 17) {

+		if (la.kind == 19) {

 			Get();

 			Expression(out range);

 		}

@@ -1798,13 +1825,13 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 			Get();

 		} else if (la.kind == 71) {

 			Get();

-		} else SynErr(162);

+		} else SynErr(164);

 	}

 

 	void LogicalExpression(out Expression/*!*/ e0) {

 		Contract.Ensures(Contract.ValueAtReturn(out e0) != null); IToken/*!*/ x;  Expression/*!*/ e1; 

 		RelationalExpression(out e0);

-		if (StartOf(17)) {

+		if (StartOf(16)) {

 			if (la.kind == 74 || la.kind == 75) {

 				AndOp();

 				x = t; 

@@ -1836,7 +1863,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 			Get();

 		} else if (la.kind == 73) {

 			Get();

-		} else SynErr(163);

+		} else SynErr(165);

 	}

 

 	void RelationalExpression(out Expression/*!*/ e) {

@@ -1853,7 +1880,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		

 		Term(out e0);

 		e = e0; 

-		if (StartOf(18)) {

+		if (StartOf(17)) {

 			RelOp(out x, out op);

 			firstOpTok = x; 

 			Term(out e1);

@@ -1861,7 +1888,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 			if (op == BinaryExpr.Opcode.Disjoint)

 			 acc = new BinaryExpr(x, BinaryExpr.Opcode.Add, e0, e1); // accumulate first two operands.

 			

-			while (StartOf(18)) {

+			while (StartOf(17)) {

 				if (chain == null) {

 				 chain = new List<Expression>();

 				 ops = new List<BinaryExpr.Opcode>();

@@ -1934,7 +1961,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 			Get();

 		} else if (la.kind == 75) {

 			Get();

-		} else SynErr(164);

+		} else SynErr(166);

 	}

 

 	void OrOp() {

@@ -1942,7 +1969,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 			Get();

 		} else if (la.kind == 77) {

 			Get();

-		} else SynErr(165);

+		} else SynErr(167);

 	}

 

 	void Term(out Expression/*!*/ e0) {

@@ -1961,17 +1988,17 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		IToken y;

 		

 		switch (la.kind) {

-		case 23: {

+		case 24: {

 			Get();

 			x = t;  op = BinaryExpr.Opcode.Eq; 

 			break;

 		}

-		case 25: {

+		case 26: {

 			Get();

 			x = t;  op = BinaryExpr.Opcode.Lt; 

 			break;

 		}

-		case 26: {

+		case 27: {

 			Get();

 			x = t;  op = BinaryExpr.Opcode.Gt; 

 			break;

@@ -2034,7 +2061,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 			x = t;  op = BinaryExpr.Opcode.Ge; 

 			break;

 		}

-		default: SynErr(166); break;

+		default: SynErr(168); break;

 		}

 	}

 

@@ -2056,7 +2083,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		} else if (la.kind == 88) {

 			Get();

 			x = t;  op = BinaryExpr.Opcode.Sub; 

-		} else SynErr(167);

+		} else SynErr(169);

 	}

 

 	void UnaryExpression(out Expression/*!*/ e) {

@@ -2076,13 +2103,13 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 			e = new UnaryExpr(x, UnaryExpr.Opcode.Not, e); 

 			break;

 		}

-		case 19: case 39: case 55: case 60: case 66: case 67: case 101: case 102: case 103: case 104: {

+		case 20: case 40: case 55: case 60: case 66: case 67: case 101: case 102: case 103: case 104: {

 			EndlessExpression(out e);

 			break;

 		}

 		case 1: {

 			DottedIdentifiersAndFunction(out e);

-			while (la.kind == 44 || la.kind == 57) {

+			while (la.kind == 14 || la.kind == 57) {

 				Suffix(ref e);

 			}

 			break;

@@ -2091,22 +2118,22 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 			DisplayExpr(out e);

 			break;

 		}

-		case 40: {

+		case 41: {

 			MultiSetExpr(out e);

 			break;

 		}

-		case 42: {

+		case 43: {

 			MapExpr(out e);

 			break;

 		}

-		case 2: case 17: case 22: case 92: case 93: case 94: case 95: case 96: case 97: case 98: {

+		case 2: case 19: case 23: case 92: case 93: case 94: case 95: case 96: case 97: case 98: {

 			ConstAtomExpression(out e);

-			while (la.kind == 44 || la.kind == 57) {

+			while (la.kind == 14 || la.kind == 57) {

 				Suffix(ref e);

 			}

 			break;

 		}

-		default: SynErr(168); break;

+		default: SynErr(170); break;

 		}

 	}

 

@@ -2121,7 +2148,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		} else if (la.kind == 90) {

 			Get();

 			x = t;  op = BinaryExpr.Opcode.Mod; 

-		} else SynErr(169);

+		} else SynErr(171);

 	}

 

 	void NegOp() {

@@ -2129,7 +2156,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 			Get();

 		} else if (la.kind == 91) {

 			Get();

-		} else SynErr(170);

+		} else SynErr(172);

 	}

 

 	void EndlessExpression(out Expression e) {

@@ -2159,7 +2186,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 			QuantifierGuts(out e);

 			break;

 		}

-		case 39: {

+		case 40: {

 			ComprehensionExpr(out e);

 			break;

 		}

@@ -2167,7 +2194,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 			Get();

 			x = t; 

 			Expression(out e0);

-			Expect(18);

+			Expect(12);

 			Expression(out e1);

 			e = new AssertExpr(x, e0, e1); 

 			break;

@@ -2176,19 +2203,19 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 			Get();

 			x = t; 

 			Expression(out e0);

-			Expect(18);

+			Expect(12);

 			Expression(out e1);

 			e = new AssumeExpr(x, e0, e1); 

 			break;

 		}

-		case 19: {

+		case 20: {

 			Get();

 			x = t;

 			letVars = new List<BoundVar>();

 			letRHSs = new List<Expression>(); 

 			IdentTypeOptional(out d);

 			letVars.Add(d); 

-			while (la.kind == 20) {

+			while (la.kind == 21) {

 				Get();

 				IdentTypeOptional(out d);

 				letVars.Add(d); 

@@ -2196,17 +2223,17 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 			Expect(53);

 			Expression(out e);

 			letRHSs.Add(e); 

-			while (la.kind == 20) {

+			while (la.kind == 21) {

 				Get();

 				Expression(out e);

 				letRHSs.Add(e); 

 			}

-			Expect(18);

+			Expect(12);

 			Expression(out e);

 			e = new LetExpr(x, letVars, letRHSs, e); 

 			break;

 		}

-		default: SynErr(171); break;

+		default: SynErr(173); break;

 		}

 	}

 

@@ -2217,18 +2244,18 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		

 		Ident(out id);

 		idents.Add(id); 

-		while (la.kind == 44) {

+		while (la.kind == 14) {

 			Get();

 			Ident(out id);

 			idents.Add(id); 

 		}

-		if (la.kind == 22) {

+		if (la.kind == 23) {

 			Get();

 			openParen = t;  args = new List<Expression>(); 

-			if (StartOf(9)) {

+			if (StartOf(8)) {

 				Expressions(args);

 			}

-			Expect(24);

+			Expect(25);

 		}

 		e = new IdentifierSequence(idents, openParen, args); 

 	}

@@ -2239,29 +2266,29 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		List<Expression> multipleIndices = null;

 		bool func = false;

 		

-		if (la.kind == 44) {

+		if (la.kind == 14) {

 			Get();

 			Ident(out id);

-			if (la.kind == 22) {

+			if (la.kind == 23) {

 				Get();

 				IToken openParen = t;  args = new List<Expression/*!*/>();  func = true; 

-				if (StartOf(9)) {

+				if (StartOf(8)) {

 					Expressions(args);

 				}

-				Expect(24);

+				Expect(25);

 				e = new FunctionCallExpr(id, id.val, e, openParen, args); 

 			}

 			if (!func) { e = new ExprDotName(id, e, id.val); } 

 		} else if (la.kind == 57) {

 			Get();

 			x = t; 

-			if (StartOf(9)) {

+			if (StartOf(8)) {

 				Expression(out ee);

 				e0 = ee; 

 				if (la.kind == 100) {

 					Get();

 					anyDots = true; 

-					if (StartOf(9)) {

+					if (StartOf(8)) {

 						Expression(out ee);

 						e1 = ee; 

 					}

@@ -2269,8 +2296,8 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 					Get();

 					Expression(out ee);

 					e1 = ee; 

-				} else if (la.kind == 20 || la.kind == 58) {

-					while (la.kind == 20) {

+				} else if (la.kind == 21 || la.kind == 58) {

+					while (la.kind == 21) {

 						Get();

 						Expression(out ee);

 						if (multipleIndices == null) {

@@ -2280,15 +2307,15 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 						multipleIndices.Add(ee);

 						

 					}

-				} else SynErr(172);

+				} else SynErr(174);

 			} else if (la.kind == 100) {

 				Get();

 				anyDots = true; 

-				if (StartOf(9)) {

+				if (StartOf(8)) {

 					Expression(out ee);

 					e1 = ee; 

 				}

-			} else SynErr(173);

+			} else SynErr(175);

 			if (multipleIndices != null) {

 			 e = new MultiSelectExpr(x, e, multipleIndices);

 			 // make sure an array class with this dimensionality exists

@@ -2312,7 +2339,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 			}

 			

 			Expect(58);

-		} else SynErr(174);

+		} else SynErr(176);

 	}

 

 	void DisplayExpr(out Expression e) {

@@ -2323,7 +2350,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		if (la.kind == 6) {

 			Get();

 			x = t;  elements = new List<Expression/*!*/>(); 

-			if (StartOf(9)) {

+			if (StartOf(8)) {

 				Expressions(elements);

 			}

 			e = new SetDisplayExpr(x, elements);

@@ -2331,12 +2358,12 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		} else if (la.kind == 57) {

 			Get();

 			x = t;  elements = new List<Expression/*!*/>(); 

-			if (StartOf(9)) {

+			if (StartOf(8)) {

 				Expressions(elements);

 			}

 			e = new SeqDisplayExpr(x, elements); 

 			Expect(58);

-		} else SynErr(175);

+		} else SynErr(177);

 	}

 

 	void MultiSetExpr(out Expression e) {

@@ -2344,25 +2371,25 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		IToken/*!*/ x = null;  List<Expression/*!*/>/*!*/ elements;

 		e = dummyExpr;

 		

-		Expect(40);

+		Expect(41);

 		x = t; 

 		if (la.kind == 6) {

 			Get();

 			elements = new List<Expression/*!*/>(); 

-			if (StartOf(9)) {

+			if (StartOf(8)) {

 				Expressions(elements);

 			}

 			e = new MultiSetDisplayExpr(x, elements);

 			Expect(7);

-		} else if (la.kind == 22) {

+		} else if (la.kind == 23) {

 			Get();

 			x = t;  elements = new List<Expression/*!*/>(); 

 			Expression(out e);

 			e = new MultiSetFormingExpr(x, e); 

-			Expect(24);

-		} else if (StartOf(19)) {

+			Expect(25);

+		} else if (StartOf(18)) {

 			SemErr("multiset must be followed by multiset literal or expression to coerce in parentheses."); 

-		} else SynErr(176);

+		} else SynErr(178);

 	}

 

 	void MapExpr(out Expression e) {

@@ -2371,12 +2398,12 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		List<ExpressionPair/*!*/>/*!*/ elements;

 		e = dummyExpr;

 		

-		Expect(42);

+		Expect(43);

 		x = t; 

 		if (la.kind == 57) {

 			Get();

 			elements = new List<ExpressionPair/*!*/>(); 

-			if (StartOf(9)) {

+			if (StartOf(8)) {

 				MapLiteralExpressions(out elements);

 			}

 			e = new MapDisplayExpr(x, elements);

@@ -2389,14 +2416,14 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 			

 			IdentTypeOptional(out bv);

 			bvars.Add(bv); 

-			Expect(17);

+			Expect(19);

 			Expression(out range);

 			QSep();

 			Expression(out body);

 			e = new MapComprehension(x, bvars, range, body); 

-		} else if (StartOf(19)) {

+		} else if (StartOf(18)) {

 			SemErr("map must be followed by literal in brackets or comprehension."); 

-		} else SynErr(177);

+		} else SynErr(179);

 	}

 

 	void ConstAtomExpression(out Expression/*!*/ e) {

@@ -2433,47 +2460,47 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		case 96: {

 			Get();

 			x = t; 

-			Expect(22);

+			Expect(23);

 			Expression(out e);

-			Expect(24);

+			Expect(25);

 			e = new FreshExpr(x, e); 

 			break;

 		}

 		case 97: {

 			Get();

 			x = t; 

-			Expect(22);

+			Expect(23);

 			Expression(out e);

-			Expect(24);

+			Expect(25);

 			e = new AllocatedExpr(x, e); 

 			break;

 		}

 		case 98: {

 			Get();

 			x = t; 

-			Expect(22);

+			Expect(23);

 			Expression(out e);

-			Expect(24);

+			Expect(25);

 			e = new OldExpr(x, e); 

 			break;

 		}

-		case 17: {

+		case 19: {

 			Get();

 			x = t; 

 			Expression(out e);

 			e = new UnaryExpr(x, UnaryExpr.Opcode.SeqLength, e); 

-			Expect(17);

+			Expect(19);

 			break;

 		}

-		case 22: {

+		case 23: {

 			Get();

 			x = t; 

 			Expression(out e);

 			e = new ParensExpression(x, e); 

-			Expect(24);

+			Expect(25);

 			break;

 		}

-		default: SynErr(178); break;

+		default: SynErr(180); break;

 		}

 	}

 

@@ -2495,7 +2522,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		Expect(53);

 		Expression(out r);

 		elements.Add(new ExpressionPair(d,r)); 

-		while (la.kind == 20) {

+		while (la.kind == 21) {

 			Get();

 			Expression(out d);

 			Expect(53);

@@ -2509,7 +2536,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 			Get();

 		} else if (la.kind == 106) {

 			Get();

-		} else SynErr(179);

+		} else SynErr(181);

 	}

 

 	void MatchExpression(out Expression/*!*/ e) {

@@ -2540,7 +2567,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		} else if (la.kind == 103 || la.kind == 104) {

 			Exists();

 			x = t; 

-		} else SynErr(180);

+		} else SynErr(182);

 		QuantifierDomain(out bvars, out attrs, out range);

 		QSep();

 		Expression(out body);

@@ -2560,16 +2587,16 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		Expression/*!*/ range;

 		Expression body = null;

 		

-		Expect(39);

+		Expect(40);

 		x = t; 

 		IdentTypeOptional(out bv);

 		bvars.Add(bv); 

-		while (la.kind == 20) {

+		while (la.kind == 21) {

 			Get();

 			IdentTypeOptional(out bv);

 			bvars.Add(bv); 

 		}

-		Expect(17);

+		Expect(19);

 		Expression(out range);

 		if (la.kind == 105 || la.kind == 106) {

 			QSep();

@@ -2589,16 +2616,16 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		Expect(62);

 		x = t; 

 		Ident(out id);

-		if (la.kind == 22) {

+		if (la.kind == 23) {

 			Get();

 			IdentTypeOptional(out bv);

 			arguments.Add(bv); 

-			while (la.kind == 20) {

+			while (la.kind == 21) {

 				Get();

 				IdentTypeOptional(out bv);

 				arguments.Add(bv); 

 			}

-			Expect(24);

+			Expect(25);

 		}

 		Expect(63);

 		Expression(out body);

@@ -2610,7 +2637,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 			Get();

 		} else if (la.kind == 102) {

 			Get();

-		} else SynErr(181);

+		} else SynErr(183);

 	}

 

 	void Exists() {

@@ -2618,7 +2645,7 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 			Get();

 		} else if (la.kind == 104) {

 			Get();

-		} else SynErr(182);

+		} else SynErr(184);

 	}

 

 	void AttributeBody(ref Attributes attrs) {

@@ -2629,10 +2656,10 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 		Expect(5);

 		Expect(1);

 		aName = t.val; 

-		if (StartOf(20)) {

+		if (StartOf(19)) {

 			AttributeArg(out aArg);

 			aArgs.Add(aArg); 

-			while (la.kind == 20) {

+			while (la.kind == 21) {

 				Get();

 				AttributeArg(out aArg);

 				aArgs.Add(aArg); 

@@ -2654,27 +2681,26 @@ List<Expression/*!*/>/*!*/ decreases, ref Attributes decAttrs, ref Attributes mo
 	}

 

 	static readonly bool[,]/*!*/ set = {

-		{T,T,T,x, x,x,T,x, T,x,x,x, T,x,T,T, x,T,T,T, x,x,T,x, x,x,x,T, T,x,T,T, T,T,T,T, x,x,x,x, x,x,x,x, x,x,x,x, x,x,T,T, T,x,x,T, x,x,x,x, T,x,x,x, T,T,T,T, T,T,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, T,T,T,T, T,T,T,x, x,x,x,x, x,x,x,x, x},

-		{x,x,x,x, x,x,x,x, T,T,x,x, T,T,T,T, x,x,x,T, x,T,x,x, x,x,x,T, T,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,T,T,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x},

-		{x,x,x,x, x,x,x,x, T,x,x,x, T,T,T,T, x,x,x,T, x,T,x,x, x,x,x,T, T,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,T,T,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x},

-		{x,x,x,x, x,x,x,x, T,x,x,x, x,T,x,x, x,x,x,T, x,x,x,x, x,x,x,T, T,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,T,T,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x},

-		{T,x,x,x, x,x,T,T, T,T,x,x, T,T,T,T, x,x,x,T, x,T,T,x, x,T,x,T, T,x,x,x, x,T,T,T, x,x,x,x, x,x,x,x, x,T,T,T, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x},

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+		{T,T,T,x, x,x,T,x, T,x,x,x, T,x,x,T, x,T,T,T, T,x,x,T, x,x,x,x, T,T,x,T, T,T,T,T, T,x,x,x, x,x,x,x, x,x,x,x, x,x,T,T, T,x,x,T, x,x,x,x, T,x,x,x, T,T,T,T, T,T,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, T,T,T,T, T,T,T,x, x,x,x,x, x,x,x,x, x},

+		{x,x,x,x, x,x,x,x, T,T,x,x, x,x,x,T, T,T,T,x, T,x,T,x, x,x,x,x, T,T,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,T,T,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x},

+		{x,x,x,x, x,x,x,x, T,x,x,x, x,x,x,x, T,x,x,x, T,x,x,x, x,x,x,x, T,T,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,T,T,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x},

+		{T,x,x,x, x,x,T,T, T,T,x,x, x,x,x,T, T,T,T,x, T,x,T,T, x,x,T,x, T,T,x,x, x,x,T,T, T,x,x,x, x,x,x,x, x,T,T,T, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x},

+		{x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,T,T, T,x,x,x, x,x,x,x, x,x,x,T, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x},

+		{x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, T,T,T,T, T,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x},

+		{x,T,x,T, x,x,x,x, T,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,T,T,T, T,T,T,T, T,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x},

+		{T,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, T,T,T,T, T,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x},

+		{x,T,T,x, x,x,T,x, x,x,x,x, x,x,x,x, x,x,x,T, T,x,x,T, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, T,T,x,T, x,x,x,x, x,x,x,x, x,x,x,T, x,T,x,x, T,x,x,x, x,x,T,T, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,T, x,x,x,x, T,x,x,T, T,T,T,T, T,T,T,x, x,T,T,T, T,x,x,x, x},

+		{x,T,T,x, x,x,T,x, T,x,x,x, x,x,x,x, x,x,x,T, T,x,x,T, x,x,x,x, x,x,x,T, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,T,T, T,x,x,T, x,x,x,x, T,x,x,x, T,x,T,T, T,T,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, T,T,T,T, T,T,T,x, x,x,x,x, x,x,x,x, x},

+		{x,T,T,x, x,x,T,x, x,x,x,x, x,x,x,x, x,x,x,T, T,x,x,T, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, T,T,x,T, x,x,x,x, T,x,x,x, x,x,x,T, x,T,x,x, T,x,x,x, x,x,T,T, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,T, x,x,x,x, T,x,x,T, T,T,T,T, T,T,T,x, x,T,T,T, T,x,x,x, x},

+		{T,T,T,x, x,x,T,x, T,x,x,x, x,x,x,x, x,x,x,T, T,x,x,T, x,x,x,x, x,x,x,T, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,T,T, T,x,x,T, x,x,x,x, T,x,x,x, T,x,T,T, T,T,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, T,T,T,T, T,T,T,x, x,x,x,x, x,x,x,x, x},

+		{x,x,x,x, x,x,T,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, T,T,x,x, T,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,T,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x},

+		{x,T,T,x, x,x,T,x, x,x,x,x, x,x,x,x, x,x,x,T, T,x,x,T, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, T,T,x,T, x,x,x,x, T,x,x,x, x,x,x,T, T,T,x,T, T,x,x,x, x,x,T,T, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,T, x,x,x,x, T,x,x,T, T,T,T,T, T,T,T,x, x,T,T,T, T,x,x,x, x},

+		{x,x,T,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,T, x,x,x,T, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, T,T,T,T, T,T,T,x, x,x,x,x, x,x,x,x, x},

+		{x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, T,T,x,x, T,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,T,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x},

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-		{x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,T, x,T,T,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,T,T, T,T,T,T, T,T,T,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x},

-		{x,x,x,x, x,x,T,T, x,x,x,x, x,x,x,x, x,T,T,x, T,x,x,T, T,T,T,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, T,T,x,x, x,T,x,x, x,x,T,x, x,T,T,T, x,x,x,x, x,x,T,T, T,T,T,T, T,T,T,T, T,T,T,T, T,T,T,T, T,T,T,x, x,x,x,x, x,x,x,T, T,x,x,x, x,T,T,x, x},

-		{x,T,T,x, T,x,T,x, x,x,x,x, x,x,x,x, x,T,x,T, x,x,T,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,T, T,x,T,x, x,x,x,x, x,x,x,x, x,x,x,T, x,T,x,x, T,x,x,x, x,x,T,T, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,T, x,x,x,x, T,x,x,T, T,T,T,T, T,T,T,x, x,T,T,T, T,x,x,x, x}

+		{x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, T,x,T,T, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,T,T, T,T,T,T, T,T,T,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x},

+		{x,x,x,x, x,x,T,T, x,x,x,x, T,x,x,x, x,x,x,T, x,T,x,x, T,T,T,T, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, T,T,x,x, x,T,x,x, x,x,T,x, x,T,T,T, x,x,x,x, x,x,T,T, T,T,T,T, T,T,T,T, T,T,T,T, T,T,T,T, T,T,T,x, x,x,x,x, x,x,x,T, T,x,x,x, x,T,T,x, x},

+		{x,T,T,x, T,x,T,x, x,x,x,x, x,x,x,x, x,x,x,T, T,x,x,T, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,x, T,T,x,T, x,x,x,x, x,x,x,x, x,x,x,T, x,T,x,x, T,x,x,x, x,x,T,T, x,x,x,x, x,x,x,x, x,x,x,x, x,x,x,T, x,x,x,x, T,x,x,T, T,T,T,T, T,T,T,x, x,T,T,T, T,x,x,x, x}

 

 	};

 } // end Parser

@@ -2710,40 +2736,40 @@ public class Errors {
 			case 8: s = "\"ghost\" expected"; break;

 			case 9: s = "\"module\" expected"; break;

 			case 10: s = "\"refines\" expected"; break;

-			case 11: s = "\"imports\" expected"; break;

-			case 12: s = "\"class\" expected"; break;

-			case 13: s = "\"static\" expected"; break;

-			case 14: s = "\"datatype\" expected"; break;

-			case 15: s = "\"codatatype\" expected"; break;

-			case 16: s = "\"=\" expected"; break;

-			case 17: s = "\"|\" expected"; break;

-			case 18: s = "\";\" expected"; break;

-			case 19: s = "\"var\" expected"; break;

-			case 20: s = "\",\" expected"; break;

-			case 21: s = "\"type\" expected"; break;

-			case 22: s = "\"(\" expected"; break;

-			case 23: s = "\"==\" expected"; break;

-			case 24: s = "\")\" expected"; break;

-			case 25: s = "\"<\" expected"; break;

-			case 26: s = "\">\" expected"; break;

-			case 27: s = "\"method\" expected"; break;

-			case 28: s = "\"constructor\" expected"; break;

-			case 29: s = "\"returns\" expected"; break;

-			case 30: s = "\"...\" expected"; break;

-			case 31: s = "\"modifies\" expected"; break;

-			case 32: s = "\"free\" expected"; break;

-			case 33: s = "\"requires\" expected"; break;

-			case 34: s = "\"ensures\" expected"; break;

-			case 35: s = "\"decreases\" expected"; break;

-			case 36: s = "\"bool\" expected"; break;

-			case 37: s = "\"nat\" expected"; break;

-			case 38: s = "\"int\" expected"; break;

-			case 39: s = "\"set\" expected"; break;

-			case 40: s = "\"multiset\" expected"; break;

-			case 41: s = "\"seq\" expected"; break;

-			case 42: s = "\"map\" expected"; break;

-			case 43: s = "\"object\" expected"; break;

-			case 44: s = "\".\" expected"; break;

+			case 11: s = "\"=\" expected"; break;

+			case 12: s = "\";\" expected"; break;

+			case 13: s = "\"as\" expected"; break;

+			case 14: s = "\".\" expected"; break;

+			case 15: s = "\"class\" expected"; break;

+			case 16: s = "\"static\" expected"; break;

+			case 17: s = "\"datatype\" expected"; break;

+			case 18: s = "\"codatatype\" expected"; break;

+			case 19: s = "\"|\" expected"; break;

+			case 20: s = "\"var\" expected"; break;

+			case 21: s = "\",\" expected"; break;

+			case 22: s = "\"type\" expected"; break;

+			case 23: s = "\"(\" expected"; break;

+			case 24: s = "\"==\" expected"; break;

+			case 25: s = "\")\" expected"; break;

+			case 26: s = "\"<\" expected"; break;

+			case 27: s = "\">\" expected"; break;

+			case 28: s = "\"method\" expected"; break;

+			case 29: s = "\"constructor\" expected"; break;

+			case 30: s = "\"returns\" expected"; break;

+			case 31: s = "\"...\" expected"; break;

+			case 32: s = "\"modifies\" expected"; break;

+			case 33: s = "\"free\" expected"; break;

+			case 34: s = "\"requires\" expected"; break;

+			case 35: s = "\"ensures\" expected"; break;

+			case 36: s = "\"decreases\" expected"; break;

+			case 37: s = "\"bool\" expected"; break;

+			case 38: s = "\"nat\" expected"; break;

+			case 39: s = "\"int\" expected"; break;

+			case 40: s = "\"set\" expected"; break;

+			case 41: s = "\"multiset\" expected"; break;

+			case 42: s = "\"seq\" expected"; break;

+			case 43: s = "\"map\" expected"; break;

+			case 44: s = "\"object\" expected"; break;

 			case 45: s = "\"function\" expected"; break;

 			case 46: s = "\"predicate\" expected"; break;

 			case 47: s = "\"reads\" expected"; break;

@@ -2808,80 +2834,82 @@ public class Errors {
 			case 106: s = "\"\\u2022\" expected"; break;

 			case 107: s = "??? expected"; break;

 			case 108: s = "invalid Dafny"; break;

-			case 109: s = "this symbol not expected in ClassDecl"; break;

-			case 110: s = "this symbol not expected in DatatypeDecl"; break;

-			case 111: s = "invalid DatatypeDecl"; break;

+			case 109: s = "invalid SubModuleDecl"; break;

+			case 110: s = "invalid SubModuleDecl"; break;

+			case 111: s = "this symbol not expected in ClassDecl"; break;

 			case 112: s = "this symbol not expected in DatatypeDecl"; break;

-			case 113: s = "this symbol not expected in ArbitraryTypeDecl"; break;

-			case 114: s = "invalid ClassMemberDecl"; break;

-			case 115: s = "this symbol not expected in FieldDecl"; break;

-			case 116: s = "this symbol not expected in FieldDecl"; break;

-			case 117: s = "invalid FunctionDecl"; break;

-			case 118: s = "invalid FunctionDecl"; break;

+			case 113: s = "invalid DatatypeDecl"; break;

+			case 114: s = "this symbol not expected in DatatypeDecl"; break;

+			case 115: s = "this symbol not expected in ArbitraryTypeDecl"; break;

+			case 116: s = "invalid ClassMemberDecl"; break;

+			case 117: s = "this symbol not expected in FieldDecl"; break;

+			case 118: s = "this symbol not expected in FieldDecl"; break;

 			case 119: s = "invalid FunctionDecl"; break;

-			case 120: s = "this symbol not expected in MethodDecl"; break;

-			case 121: s = "invalid MethodDecl"; break;

-			case 122: s = "invalid MethodDecl"; break;

-			case 123: s = "invalid TypeAndToken"; break;

-			case 124: s = "this symbol not expected in MethodSpec"; break;

-			case 125: s = "this symbol not expected in MethodSpec"; break;

+			case 120: s = "invalid FunctionDecl"; break;

+			case 121: s = "invalid FunctionDecl"; break;

+			case 122: s = "this symbol not expected in MethodDecl"; break;

+			case 123: s = "invalid MethodDecl"; break;

+			case 124: s = "invalid MethodDecl"; break;

+			case 125: s = "invalid TypeAndToken"; break;

 			case 126: s = "this symbol not expected in MethodSpec"; break;

 			case 127: s = "this symbol not expected in MethodSpec"; break;

-			case 128: s = "invalid MethodSpec"; break;

+			case 128: s = "this symbol not expected in MethodSpec"; break;

 			case 129: s = "this symbol not expected in MethodSpec"; break;

 			case 130: s = "invalid MethodSpec"; break;

-			case 131: s = "invalid ReferenceType"; break;

-			case 132: s = "this symbol not expected in FunctionSpec"; break;

-			case 133: s = "this symbol not expected in FunctionSpec"; break;

+			case 131: s = "this symbol not expected in MethodSpec"; break;

+			case 132: s = "invalid MethodSpec"; break;

+			case 133: s = "invalid ReferenceType"; break;

 			case 134: s = "this symbol not expected in FunctionSpec"; break;

 			case 135: s = "this symbol not expected in FunctionSpec"; break;

 			case 136: s = "this symbol not expected in FunctionSpec"; break;

-			case 137: s = "invalid FunctionSpec"; break;

-			case 138: s = "invalid PossiblyWildFrameExpression"; break;

-			case 139: s = "invalid PossiblyWildExpression"; break;

-			case 140: s = "this symbol not expected in OneStmt"; break;

-			case 141: s = "invalid OneStmt"; break;

+			case 137: s = "this symbol not expected in FunctionSpec"; break;

+			case 138: s = "this symbol not expected in FunctionSpec"; break;

+			case 139: s = "invalid FunctionSpec"; break;

+			case 140: s = "invalid PossiblyWildFrameExpression"; break;

+			case 141: s = "invalid PossiblyWildExpression"; break;

 			case 142: s = "this symbol not expected in OneStmt"; break;

 			case 143: s = "invalid OneStmt"; break;

-			case 144: s = "invalid AssertStmt"; break;

-			case 145: s = "invalid AssumeStmt"; break;

-			case 146: s = "invalid UpdateStmt"; break;

-			case 147: s = "invalid UpdateStmt"; break;

-			case 148: s = "invalid IfStmt"; break;

-			case 149: s = "invalid IfStmt"; break;

-			case 150: s = "invalid WhileStmt"; break;

-			case 151: s = "invalid WhileStmt"; break;

-			case 152: s = "invalid Rhs"; break;

-			case 153: s = "invalid Lhs"; break;

-			case 154: s = "invalid Guard"; break;

-			case 155: s = "this symbol not expected in LoopSpec"; break;

-			case 156: s = "this symbol not expected in LoopSpec"; break;

+			case 144: s = "this symbol not expected in OneStmt"; break;

+			case 145: s = "invalid OneStmt"; break;

+			case 146: s = "invalid AssertStmt"; break;

+			case 147: s = "invalid AssumeStmt"; break;

+			case 148: s = "invalid UpdateStmt"; break;

+			case 149: s = "invalid UpdateStmt"; break;

+			case 150: s = "invalid IfStmt"; break;

+			case 151: s = "invalid IfStmt"; break;

+			case 152: s = "invalid WhileStmt"; break;

+			case 153: s = "invalid WhileStmt"; break;

+			case 154: s = "invalid Rhs"; break;

+			case 155: s = "invalid Lhs"; break;

+			case 156: s = "invalid Guard"; break;

 			case 157: s = "this symbol not expected in LoopSpec"; break;

 			case 158: s = "this symbol not expected in LoopSpec"; break;

 			case 159: s = "this symbol not expected in LoopSpec"; break;

-			case 160: s = "this symbol not expected in Invariant"; break;

-			case 161: s = "invalid AttributeArg"; break;

-			case 162: s = "invalid EquivOp"; break;

-			case 163: s = "invalid ImpliesOp"; break;

-			case 164: s = "invalid AndOp"; break;

-			case 165: s = "invalid OrOp"; break;

-			case 166: s = "invalid RelOp"; break;

-			case 167: s = "invalid AddOp"; break;

-			case 168: s = "invalid UnaryExpression"; break;

-			case 169: s = "invalid MulOp"; break;

-			case 170: s = "invalid NegOp"; break;

-			case 171: s = "invalid EndlessExpression"; break;

-			case 172: s = "invalid Suffix"; break;

-			case 173: s = "invalid Suffix"; break;

+			case 160: s = "this symbol not expected in LoopSpec"; break;

+			case 161: s = "this symbol not expected in LoopSpec"; break;

+			case 162: s = "this symbol not expected in Invariant"; break;

+			case 163: s = "invalid AttributeArg"; break;

+			case 164: s = "invalid EquivOp"; break;

+			case 165: s = "invalid ImpliesOp"; break;

+			case 166: s = "invalid AndOp"; break;

+			case 167: s = "invalid OrOp"; break;

+			case 168: s = "invalid RelOp"; break;

+			case 169: s = "invalid AddOp"; break;

+			case 170: s = "invalid UnaryExpression"; break;

+			case 171: s = "invalid MulOp"; break;

+			case 172: s = "invalid NegOp"; break;

+			case 173: s = "invalid EndlessExpression"; break;

 			case 174: s = "invalid Suffix"; break;

-			case 175: s = "invalid DisplayExpr"; break;

-			case 176: s = "invalid MultiSetExpr"; break;

-			case 177: s = "invalid MapExpr"; break;

-			case 178: s = "invalid ConstAtomExpression"; break;

-			case 179: s = "invalid QSep"; break;

-			case 180: s = "invalid QuantifierGuts"; break;

-			case 181: s = "invalid Forall"; break;

-			case 182: s = "invalid Exists"; break;

+			case 175: s = "invalid Suffix"; break;

+			case 176: s = "invalid Suffix"; break;

+			case 177: s = "invalid DisplayExpr"; break;

+			case 178: s = "invalid MultiSetExpr"; break;

+			case 179: s = "invalid MapExpr"; break;

+			case 180: s = "invalid ConstAtomExpression"; break;

+			case 181: s = "invalid QSep"; break;

+			case 182: s = "invalid QuantifierGuts"; break;

+			case 183: s = "invalid Forall"; break;

+			case 184: s = "invalid Exists"; break;

 

 			default: s = "error " + n; break;

 		}

diff --git a/Source/Dafny/Printer.cs b/Source/Dafny/Printer.cs
index 3654c672..a49a906e 100644
--- a/Source/Dafny/Printer.cs
+++ b/Source/Dafny/Printer.cs
@@ -32,33 +32,8 @@ namespace Microsoft.Dafny {
         wr.WriteLine("// " + Bpl.CommandLineOptions.Clo.Environment);

       }

       wr.WriteLine("// {0}", prog.Name);

-      foreach (ModuleDecl module in prog.Modules) {

-        wr.WriteLine();

-        if (module.IsDefaultModule) {

-          PrintTopLevelDecls(module.TopLevelDecls, 0);

-        } else {

-          wr.Write("module");

-          PrintAttributes(module.Attributes);

-          wr.Write(" {0} ", module.Name);

-          if (module.RefinementBaseName != null) {

-            wr.Write("refines {0} ", module.RefinementBaseName);

-          }

-          if (module.ImportNames.Count != 0) {

-            string sep = "imports ";

-            foreach (string imp in module.ImportNames) {

-              wr.Write("{0}{1}", sep, imp);

-              sep = ", ";

-            }

-          }

-          if (module.TopLevelDecls.Count == 0) {

-            wr.WriteLine(" { }");

-          } else {

-            wr.WriteLine(" {");

-            PrintTopLevelDecls(module.TopLevelDecls, IndentAmount);

-            wr.WriteLine("}");

-          }

-        }

-      }

+      wr.WriteLine();

+      PrintTopLevelDecls(prog.DefaultModuleDef.TopLevelDecls, 0);

     }

 

     public void PrintTopLevelDecls(List<TopLevelDecl> classes, int indent) {

@@ -78,7 +53,7 @@ namespace Microsoft.Dafny {
         } else if (d is DatatypeDecl) {

           if (i++ != 0) { wr.WriteLine(); }

           PrintDatatype((DatatypeDecl)d, indent);

-        } else {

+        } else if (d is ClassDecl) {

           ClassDecl cl = (ClassDecl)d;

           if (!cl.IsDefaultClass) {

             if (i++ != 0) { wr.WriteLine(); }

@@ -89,6 +64,34 @@ namespace Microsoft.Dafny {
             if (i++ != 0) { wr.WriteLine(); }

             PrintClass_Members(cl, indent);

           }

+        } else if (d is ModuleDecl) {

+          wr.WriteLine();

+          Indent(indent);

+          if (d is LiteralModuleDecl) {

+            ModuleDefinition module = ((LiteralModuleDecl)d).ModuleDef;

+            wr.Write("module");

+            PrintAttributes(module.Attributes);

+            wr.Write(" {0} ", module.Name);

+            if (module.RefinementBaseName != null) {

+              wr.Write("refines {0} ", Util.Comma(".", module.RefinementBaseName, id => id.val));

+            }

+            if (module.TopLevelDecls.Count == 0) {

+              wr.WriteLine("{ }");

+            } else {

+              wr.WriteLine("{");

+              PrintTopLevelDecls(module.TopLevelDecls, indent + IndentAmount);

+              Indent(indent);

+              wr.WriteLine("}");

+            }

+          } else if (d is AliasModuleDecl) {

+            wr.Write("module");

+            wr.Write(" {0} ", ((AliasModuleDecl)d).Name);

+            wr.WriteLine("= {0};", Util.Comma(".", ((AliasModuleDecl)d).Path, id => id.val));

+          } else if (d is AbstractModuleDecl) {

+            wr.Write("module");

+            wr.Write(" {0} ", ((AbstractModuleDecl)d).Name);

+            wr.WriteLine("as {0};", Util.Comma(".", ((AbstractModuleDecl)d).Path, id => id.val));

+          }

         }

       }

     }

@@ -147,17 +150,10 @@ namespace Microsoft.Dafny {
 

       wr.Write(" {0}", name);

       if (typeArgs.Count != 0) {

-        wr.Write("<");

-        string sep = "";

-        foreach (TypeParameter tp in typeArgs) {

-          Contract.Assert(tp != null);

-          wr.Write("{0}{1}", sep, tp.Name);

-          if (tp.EqualitySupport == TypeParameter.EqualitySupportValue.Required) {

-            wr.Write("(==)");

-          }

-          sep = ", ";

-        }

-        wr.Write(">");

+        wr.Write("<" +

+                 Util.Comma(", ", typeArgs,

+                   tp => tp.Name + (tp.EqualitySupport == TypeParameter.EqualitySupportValue.Required? "(==)": ""))

+                 + ">");

       }

     }

 

@@ -262,7 +258,7 @@ namespace Microsoft.Dafny {
 

     // ----------------------------- PrintMethod -----------------------------

 

-    const int IndentAmount = 2;

+    const int IndentAmount = 2; // The amount of indent for each new scope

     const string BunchaSpaces = "                                ";

     void Indent(int amount)

     {  Contract.Requires( 0 <= amount);

diff --git a/Source/Dafny/RefinementTransformer.cs b/Source/Dafny/RefinementTransformer.cs
index bbc12d6a..0d32e24e 100644
--- a/Source/Dafny/RefinementTransformer.cs
+++ b/Source/Dafny/RefinementTransformer.cs
@@ -21,8 +21,8 @@ using IToken = Microsoft.Boogie.IToken;
 namespace Microsoft.Dafny {

   public class RefinementToken : TokenWrapper

   {

-    public readonly ModuleDecl InheritingModule;

-    public RefinementToken(IToken tok, ModuleDecl m)

+    public readonly ModuleDefinition InheritingModule;

+    public RefinementToken(IToken tok, ModuleDefinition m)

       : base(tok)

     {

       Contract.Requires(tok != null);

@@ -30,7 +30,7 @@ namespace Microsoft.Dafny {
       this.InheritingModule = m;

     }

 

-    public static bool IsInherited(IToken tok, ModuleDecl m) {

+    public static bool IsInherited(IToken tok, ModuleDefinition m) {

       while (tok is NestedToken) {

         var n = (NestedToken)tok;

         // check Outer

@@ -58,33 +58,19 @@ namespace Microsoft.Dafny {
       this.reporter = reporter;

     }

 

-    private ModuleDecl moduleUnderConstruction;  // non-null for the duration of Construct calls

+    private ModuleDefinition moduleUnderConstruction;  // non-null for the duration of Construct calls

     private Queue<Action> postTasks = new Queue<Action>();  // empty whenever moduleUnderConstruction==null, these tasks are for the post-resolve phase of module moduleUnderConstruction

 

-    public void PreResolve(ModuleDecl m) {

-      if (m.RefinementBase == null) {

-        // This Rewriter doesn't do anything

-        return;

-      }

+    public void PreResolve(ModuleDefinition m) {

+      Contract.Requires(m != null);

+      Contract.Requires(m.RefinementBase != null);

 

       if (moduleUnderConstruction != null) {

         postTasks.Clear();

       }

+      

       moduleUnderConstruction = m;

-      var prev = m.RefinementBase;

-

-      // Include the imports of the base.  Note, prev is itself NOT added as an import

-      // of m; instead, the contents from prev is merged directly into m.

-      // (Here, we change the import declarations.  But edges for these imports will

-      // not be added to the importGraph of the calling resolver.  However, the refines

-      // clause gave rise to an edge in the importGraph, so the transitive import edges

-      // are represented in the importGraph.)

-      foreach (var im in prev.Imports) {

-        if (!m.ImportNames.Contains(im.Name)) {

-          m.ImportNames.Add(im.Name);

-          m.Imports.Add(im);

-        }

-      }

+      var prev = m.RefinementBase;     

 

       // Create a simple name-to-decl dictionary.  Ignore any duplicates at this time.

       var declaredNames = new Dictionary<string, int>();

@@ -96,40 +82,71 @@ namespace Microsoft.Dafny {
       }

 

       // Merge the declarations of prev into the declarations of m

-

       foreach (var d in prev.TopLevelDecls) {

         int index;

         if (!declaredNames.TryGetValue(d.Name, out index)) {

           m.TopLevelDecls.Add(CloneDeclaration(d, m));

         } else {

           var nw = m.TopLevelDecls[index];

-          if (d is ArbitraryTypeDecl) {

-            bool dDemandsEqualitySupport = ((ArbitraryTypeDecl)d).MustSupportEquality;

-            if (nw is ArbitraryTypeDecl) {

-              if (dDemandsEqualitySupport != ((ArbitraryTypeDecl)nw).MustSupportEquality) {

-                reporter.Error(nw, "type declaration '{0}' is not allowed to change the requirement of supporting equality", nw.Name);

+          if (d is ModuleDecl) {

+            if (!(nw is ModuleDecl)) {

+              reporter.Error(nw, "a module ({0}) must refine another module", nw.Name);

+            } else if (!(d is AbstractModuleDecl)) {

+              reporter.Error(nw, "a module ({0}) can only refine abstract modules", nw.Name);

+            } else {

+              ModuleSignature original = ((AbstractModuleDecl)d).OriginalSignature;

+              ModuleSignature derived = null;

+              if (nw is AliasModuleDecl) {

+                derived = ((AliasModuleDecl)nw).Signature;

+              } else if (nw is AbstractModuleDecl) {

+                derived = ((AbstractModuleDecl)nw).Signature;

+              } else {

+                reporter.Error(nw, "a module ({0}) can only be refined by alias or abstract modules", d.Name);

               }

-            } else if (dDemandsEqualitySupport) {

-              if (nw is ClassDecl) {

-                // fine, as long as "nw" does not take any type parameters

-                if (nw.TypeArgs.Count != 0) {

-                  reporter.Error(nw, "arbitrary type '{0}' is not allowed to be replaced by a class that takes type parameters", nw.Name);

+              if (derived != null) {

+                // check that the new module refines the previous declaration

+                while (derived != null) {

+                  if (derived == original)

+                    break;

+                  derived = derived.Refines;

                 }

-              } else if (nw is CoDatatypeDecl) {

-                reporter.Error(nw, "a type declaration that requires equality support cannot be replaced by a codatatype");

-              } else {

-                Contract.Assert(nw is IndDatatypeDecl);

-                if (nw.TypeArgs.Count != 0) {

-                  reporter.Error(nw, "arbitrary type '{0}' is not allowed to be replaced by a datatype that takes type parameters", nw.Name);

+                if (derived != original) {

+                  reporter.Error(nw, "a module ({0}) can only be replaced by a refinement of the original module", d.Name);

+                }

+              }

+            }

+          } else if (d is ArbitraryTypeDecl) {

+            if (nw is ModuleDecl) {

+              reporter.Error(nw, "a module ({0}) must refine another module", nw.Name);

+            } else {

+              bool dDemandsEqualitySupport = ((ArbitraryTypeDecl)d).MustSupportEquality;

+              if (nw is ArbitraryTypeDecl) {

+                if (dDemandsEqualitySupport != ((ArbitraryTypeDecl)nw).MustSupportEquality) {

+                  reporter.Error(nw, "type declaration '{0}' is not allowed to change the requirement of supporting equality", nw.Name);

+                }

+              } else if (dDemandsEqualitySupport) {

+                if (nw is ClassDecl) {

+                  // fine, as long as "nw" does not take any type parameters

+                  if (nw.TypeArgs.Count != 0) {

+                    reporter.Error(nw, "arbitrary type '{0}' is not allowed to be replaced by a class that takes type parameters", nw.Name);

+                  }

+                } else if (nw is CoDatatypeDecl) {

+                  reporter.Error(nw, "a type declaration that requires equality support cannot be replaced by a codatatype");

                 } else {

-                  // Here, we need to figure out if the new type supports equality.  But we won't know about that until resolution has

-                  // taken place, so we defer it until the PostResolve phase.

-                  var udt = new UserDefinedType(nw.tok, nw.Name, nw, new List<Type>());

-                  postTasks.Enqueue(delegate() {

-                    if (!udt.SupportsEquality) {

-                      reporter.Error(udt.tok, "datatype '{0}' is used to refine an arbitrary type with equality support, but '{0}' does not support equality", udt.Name);

-                    }

-                  });

+                  Contract.Assert(nw is IndDatatypeDecl);

+                  if (nw.TypeArgs.Count != 0) {

+                    reporter.Error(nw, "arbitrary type '{0}' is not allowed to be replaced by a datatype that takes type parameters", nw.Name);

+                  } else {

+                    // Here, we need to figure out if the new type supports equality.  But we won't know about that until resolution has

+                    // taken place, so we defer it until the PostResolve phase.

+                    var udt = new UserDefinedType(nw.tok, nw.Name, nw, new List<Type>());

+                    postTasks.Enqueue(delegate()

+                    {

+                      if (!udt.SupportsEquality) {

+                        reporter.Error(udt.tok, "datatype '{0}' is used to refine an arbitrary type with equality support, but '{0}' does not support equality", udt.Name);

+                      }

+                    });

+                  }

                 }

               }

             }

@@ -151,7 +168,7 @@ namespace Microsoft.Dafny {
       Contract.Assert(moduleUnderConstruction == m);  // this should be as it was set earlier in this method

     }

 

-    public void PostResolve(ModuleDecl m) {

+    public void PostResolve(ModuleDefinition m) {

       if (m == moduleUnderConstruction) {

         while (this.postTasks.Count != 0) {

           var a = postTasks.Dequeue();

@@ -173,7 +190,8 @@ namespace Microsoft.Dafny {
 

     // -------------------------------------------------- Cloning ---------------------------------------------------------------

 

-    TopLevelDecl CloneDeclaration(TopLevelDecl d, ModuleDecl m) {

+    // Clone a toplevel, specifying that its parent module should be m (i.e. it will be added to m.TopLevelDecls).

+    TopLevelDecl CloneDeclaration(TopLevelDecl d, ModuleDefinition m) {

       Contract.Requires(d != null);

       Contract.Requires(m != null);

 

@@ -198,6 +216,25 @@ namespace Microsoft.Dafny {
         var mm = dd.Members.ConvertAll(CloneMember);

         var cl = new ClassDecl(Tok(dd.tok), dd.Name, m, tps, mm, null);

         return cl;

+      } else if (d is ModuleDecl) {

+        if (d is LiteralModuleDecl) {

+          return new LiteralModuleDecl(((LiteralModuleDecl)d).ModuleDef,m);

+        } else if (d is AliasModuleDecl) {

+          var a = (AliasModuleDecl)d;

+          var alias = new AliasModuleDecl(a.Path, a.tok, m);

+          alias.ModuleReference = a.ModuleReference;

+          alias.Signature = a.Signature;

+          return alias;

+        } else if (d is AbstractModuleDecl) {

+          var a = (AbstractModuleDecl)d;

+          var abs = new AbstractModuleDecl(a.Path, a.tok, m);

+          abs.Signature = a.Signature;

+          abs.OriginalSignature = a.OriginalSignature;

+          return abs;

+        } else {

+          Contract.Assert(false);  // unexpected declaration

+          return null;  // to please compiler

+        }

       } else {

         Contract.Assert(false);  // unexpected declaration

         return null;  // to please compiler

@@ -1217,7 +1254,7 @@ namespace Microsoft.Dafny {
 

     // ---------------------- additional methods -----------------------------------------------------------------------------

 

-    public static bool ContainsChange(Expression expr, ModuleDecl m) {

+    public static bool ContainsChange(Expression expr, ModuleDefinition m) {

       Contract.Requires(expr != null);

       Contract.Requires(m != null);

 

diff --git a/Source/Dafny/Resolver.cs b/Source/Dafny/Resolver.cs
index 3d99f732..098bcc2e 100644
--- a/Source/Dafny/Resolver.cs
+++ b/Source/Dafny/Resolver.cs
@@ -63,12 +63,15 @@ namespace Microsoft.Dafny {
   public class Resolver : ResolutionErrorReporter {

     readonly BuiltIns builtIns;

 

-    Dictionary<string/*!*/,TopLevelDecl/*!*/>/*!*/ classes;  // can map to AmbiguousTopLevelDecl

+    //Dictionary<string/*!*/,TopLevelDecl/*!*/>/*!*/ classes;  // can map to AmbiguousTopLevelDecl

+    //Dictionary<string, ModuleDecl> importedNames; // the imported modules, as a map.

+    ModuleSignature moduleInfo = null;

+

     class AmbiguousTopLevelDecl : TopLevelDecl  // only used with "classes"

     {

       readonly TopLevelDecl A;

       readonly TopLevelDecl B;

-      public AmbiguousTopLevelDecl(ModuleDecl m, TopLevelDecl a, TopLevelDecl b)

+      public AmbiguousTopLevelDecl(ModuleDefinition m, TopLevelDecl a, TopLevelDecl b)

         : base(a.tok, a.Name + "/" + b.Name, m, new List<TypeParameter>(), null) {

         A = a;

         B = b;

@@ -88,13 +91,12 @@ namespace Microsoft.Dafny {
         return nm;

       }

     }

-    Dictionary<string/*!*/, Tuple<DatatypeCtor, bool>> allDatatypeCtors;

+    //Dictionary<string/*!*/, Tuple<DatatypeCtor, bool>> allDatatypeCtors;

 

     readonly Dictionary<ClassDecl/*!*/, Dictionary<string/*!*/, MemberDecl/*!*/>/*!*/>/*!*/ classMembers = new Dictionary<ClassDecl/*!*/, Dictionary<string/*!*/, MemberDecl/*!*/>/*!*/>();

     readonly Dictionary<DatatypeDecl/*!*/, Dictionary<string/*!*/, MemberDecl/*!*/>/*!*/>/*!*/ datatypeMembers = new Dictionary<DatatypeDecl/*!*/, Dictionary<string/*!*/, MemberDecl/*!*/>/*!*/>();

     readonly Dictionary<DatatypeDecl/*!*/, Dictionary<string/*!*/, DatatypeCtor/*!*/>/*!*/>/*!*/ datatypeCtors = new Dictionary<DatatypeDecl/*!*/, Dictionary<string/*!*/, DatatypeCtor/*!*/>/*!*/>();

-    readonly Graph<ModuleDecl/*!*/>/*!*/ importGraph = new Graph<ModuleDecl/*!*/>();

-

+    readonly Graph<ModuleDecl/*!*/>/*!*/ dependencies = new Graph<ModuleDecl/*!*/>();

     public Resolver(Program prog) {

       Contract.Requires(prog != null);

       builtIns = prog.BuiltIns;

@@ -103,106 +105,113 @@ namespace Microsoft.Dafny {
     [ContractInvariantMethod]

     void ObjectInvariant() {

       Contract.Invariant(builtIns != null);

-      Contract.Invariant(cce.NonNullElements(importGraph));

+      Contract.Invariant(cce.NonNullElements(dependencies));

       Contract.Invariant(cce.NonNullDictionaryAndValues(classMembers) && Contract.ForAll(classMembers.Values, v => cce.NonNullDictionaryAndValues(v)));

       Contract.Invariant(cce.NonNullDictionaryAndValues(datatypeCtors) && Contract.ForAll(datatypeCtors.Values, v => cce.NonNullDictionaryAndValues(v)));

     }

 

     public void ResolveProgram(Program prog) {

       Contract.Requires(prog != null);

-      // register modules

-      var modules = new Dictionary<string,ModuleDecl>();

-      foreach (var m in prog.Modules) {

-        if (modules.ContainsKey(m.Name)) {

-          Error(m, "Duplicate module name: {0}", m.Name);

-        } else {

-          modules.Add(m.Name, m);

-        }

-      }

-      // resolve refines and imports

-      foreach (var m in prog.Modules) {

-        importGraph.AddVertex(m);

-        if (m.RefinementBaseName != null) {

-          ModuleDecl other;

-          if (!modules.TryGetValue(m.RefinementBaseName, out other)) {

-            Error(m, "module {0} named as refinement base does not exist", m.RefinementBaseName);

-          } else if (other == m) {

-            Error(m, "module cannot refine itself: {0}", m.RefinementBaseName);

-          } else {

-            Contract.Assert(other != null);  // follows from postcondition of TryGetValue

-            importGraph.AddEdge(m, other);

-            m.RefinementBase = other;

-          }

-        }

-        foreach (string imp in m.ImportNames) {

-          ModuleDecl other;

-          if (!modules.TryGetValue(imp, out other)) {

-            Error(m, "module {0} named among imports does not exist", imp);

-          } else if (other == m) {

-            Error(m, "module must not import itself: {0}", imp);

-          } else {

-            Contract.Assert(other != null);  // follows from postcondition of TryGetValue

-            importGraph.AddEdge(m, other);

-            m.Imports.Add(other);

-          }

-        }

-      }

+      var bindings = new ModuleBindings(null);

+      var b = BindModuleNames(prog.DefaultModuleDef, bindings);

+      bindings.BindName("_module", prog.DefaultModule , b);

+      if (ErrorCount > 0) { return; } // if there were errors, then the implict ModuleBindings data structure invariant

+                                      // is violated, so Processing dependencies will not succeed.

+      ProcessDependencies(prog.DefaultModule, b, dependencies);

       // check for cycles in the import graph

-      List<ModuleDecl> cycle = importGraph.TryFindCycle();

+      List<ModuleDecl> cycle = dependencies.TryFindCycle();

       if (cycle != null) {

-        string cy = "";

-        string sep = "";

-        foreach (ModuleDecl m in cycle) {

-          cy = m.Name + sep + cy;

-          sep = " -> ";

-        }

-        Error(cycle[0], "import graph contains a cycle: {0}", cy);

-        return;  // give up on trying to resolve anything else

+        var cy = Util.Comma(" -> ", cycle, m => m.Name);

+        Error(cycle[0], "module definition contains a cycle (note: parent modules implicitly depend on submodules): {0}", cy);

       }

+      if (ErrorCount > 0) { return; } // give up on trying to resolve anything else

 

       // fill in module heights

-      List<ModuleDecl> mm = importGraph.TopologicallySortedComponents();

-      Contract.Assert(mm.Count == prog.Modules.Count);  // follows from the fact that there are no cycles

+      List<ModuleDecl> sortedDecls = dependencies.TopologicallySortedComponents();

       int h = 0;

-      foreach (ModuleDecl m in mm) {

+      foreach (ModuleDecl m in sortedDecls) {

         m.Height = h;

+        if (m is LiteralModuleDecl) {

+          var mdef = ((LiteralModuleDecl)m).ModuleDef;

+          mdef.Height = h;

+          prog.Modules.Add(mdef);

+        }

         h++;

       }

 

-      // register top-level declarations

-      var rewriters = new List<IRewriter>();

-      // The following line could be generalized to allow rewriter plug-ins; to support such, just add command-line

-      // switches and .Add to "rewriters" here.

-      rewriters.Add(new AutoContractsRewriter());

-      rewriters.Add(new RefinementTransformer(this));

-

-      var systemNameInfo = RegisterTopLevelDecls(prog.BuiltIns.SystemModule.TopLevelDecls);

-      var moduleNameInfo = new ModuleNameInformation[h];

-      foreach (var m in mm) {

-        rewriters.Iter(r => r.PreResolve(m));

-

-        moduleNameInfo[m.Height] = RegisterTopLevelDecls(m.TopLevelDecls);

-

-        // set up environment

-        ModuleNameInformation info = ModuleNameInformation.Merge(m, systemNameInfo, moduleNameInfo);

-        classes = info.Classes;

-        allDatatypeCtors = info.Ctors;

-        // resolve

-        var datatypeDependencies = new Graph<IndDatatypeDecl>();

-        int prevErrorCount = ErrorCount;

-        ResolveTopLevelDecls_Signatures(m.TopLevelDecls, datatypeDependencies);

-        if (prevErrorCount == ErrorCount) {

+      var refinementTransformer = new RefinementTransformer(this);

+      

+      //Rewriter rewriter = new AutoContractsRewriter();

+      var systemNameInfo = RegisterTopLevelDecls(prog.BuiltIns.SystemModule);

+      foreach (var decl in sortedDecls) {

+        if (decl is LiteralModuleDecl) {

+          // The declaration is a literal module, so it has members and such that we need

+          // to resolve. First we do refinement transformation. Then we construct the signature

+          // of the module. This is the public, externally visible signature. Then we add in 

+          // everything that the system defines, as well as any "import" (i.e. "opened" modules)

+          // directives (currently not supported, but this is where we would do it.) This signature,

+          // which is only used while resolving the members of the module is stored in the (basically)

+          // global variable moduleInfo. Then the signatures of the module members are resolved, followed

+          // by the bodies.

+          var literalDecl = (LiteralModuleDecl)decl;

+          var m = (literalDecl).ModuleDef;

+          //rewriter.PreResolve(m);

+          ModuleSignature refinedSig = null;

+          if (m.RefinementBaseRoot != null) {

+            if (ResolvePath(m.RefinementBaseRoot, m.RefinementBaseName, out refinedSig)) {

+              if (refinedSig.ModuleDef != null) {

+                m.RefinementBase = refinedSig.ModuleDef;

+                refinementTransformer.PreResolve(m);

+              } else {

+                Error(m.RefinementBaseName[0], "module ({0}) named as refinement base is not a literal module or simple reference to a literal module", Util.Comma(".", m.RefinementBaseName, x => x.val));

+              }

+            } else {

+              Error(m.RefinementBaseName[0], "module ({0}) named as refinement base does not exist", Util.Comma(".", m.RefinementBaseName, x => x.val));

+            }

+          }

+          literalDecl.Signature = RegisterTopLevelDecls(m);

+          literalDecl.Signature.Refines = refinedSig;

+          // set up environment

+          moduleInfo = MergeSignature(literalDecl.Signature, systemNameInfo);

+          // resolve

+          var datatypeDependencies = new Graph<IndDatatypeDecl>();

+          int prevErrorCount = ErrorCount;

+          ResolveTopLevelDecls_Signatures(m.TopLevelDecls, datatypeDependencies);

+          if (ErrorCount == prevErrorCount)

           ResolveTopLevelDecls_Meat(m.TopLevelDecls, datatypeDependencies);

-        }

-        // tear down

-        classes = null;

-        allDatatypeCtors = null;

-        // give rewriters a chance to do processing

-        rewriters.Iter(r => r.PostResolve(m));

-      }

 

+          refinementTransformer.PostResolve(m);

+          // give rewriter a chance to do processing

+          //rewriter.PostResolve(m);

+        } else if (decl is AliasModuleDecl) {

+          var alias = (AliasModuleDecl)decl;

+          // resolve the path

+          ModuleSignature p;

+          if (ResolvePath(alias.Root, alias.Path, out p)) {

+            alias.Signature = p;

+          } else {

+            alias.Signature = new ModuleSignature(); // there was an error, give it a valid but empty signature

+          }

+        } else if (decl is AbstractModuleDecl) {

+          var abs = (AbstractModuleDecl)decl;

+          ModuleSignature p; ModuleDefinition mod;

+          if (ResolvePath(abs.Root, abs.Path, out p)) {

+            abs.Signature = MakeAbstractSignature(p, abs.Name, abs.Height, out mod);

+            abs.OriginalSignature = p;

+            moduleInfo = MergeSignature(abs.Signature, systemNameInfo);

+            // resolve

+            var datatypeDependencies = new Graph<IndDatatypeDecl>();

+            ResolveTopLevelDecls_Signatures(mod.TopLevelDecls, datatypeDependencies);

+            ResolveTopLevelDecls_Meat(mod.TopLevelDecls, datatypeDependencies);

+            prog.Modules.Add(mod);

+          } else {

+            abs.Signature = new ModuleSignature(); // there was an error, give it a valid but empty signature

+          }

+        } else { Contract.Assert(false); }

+        Contract.Assert(decl.Signature != null);

+      }

       // compute IsRecursive bit for mutually recursive functions

-      foreach (ModuleDecl m in mm) {

+      foreach (ModuleDefinition m in prog.Modules) {

         foreach (TopLevelDecl decl in m.TopLevelDecls) {

           ClassDecl cl = decl as ClassDecl;

           if (cl != null) {

@@ -219,72 +228,159 @@ namespace Microsoft.Dafny {
           }

         }

       }

+      

     }

 

-    class ModuleNameInformation

-    {

-      public readonly Dictionary<string, TopLevelDecl> Classes = new Dictionary<string, TopLevelDecl>();

-      public readonly Dictionary<string, Tuple<DatatypeCtor, bool>> Ctors = new Dictionary<string,Tuple<DatatypeCtor,bool>>();

-

-      public static ModuleNameInformation Merge(ModuleDecl m, ModuleNameInformation system, ModuleNameInformation[] modules) {

-        var info = new ModuleNameInformation();

-        // add the system-declared information, among which we know there are no duplicates

-        foreach (var kv in system.Classes) {

-          info.Classes.Add(kv.Key, kv.Value);

-        }

-        foreach (var kv in system.Ctors) {

-          info.Ctors.Add(kv.Key, kv.Value);

-        }

-        // for each imported module, add its information, noting any duplicates

-        foreach (var im in m.Imports) {

-          Contract.Assume(0 <= im.Height && im.Height < m.Height);

-          var import = modules[im.Height];

-          // classes:

-          foreach (var kv in import.Classes) {

-            TopLevelDecl d;

-            if (info.Classes.TryGetValue(kv.Key, out d)) {

-              info.Classes[kv.Key] = new AmbiguousTopLevelDecl(m, d, kv.Value);

-            } else {

-              info.Classes.Add(kv.Key, kv.Value);

-            }

+

+    public class ModuleBindings {

+      private ModuleBindings parent;

+      private Dictionary<string, ModuleDecl> modules;

+      private Dictionary<string, ModuleBindings> bindings;

+

+      public ModuleBindings(ModuleBindings p) {

+        parent = p;

+        modules = new Dictionary<string, ModuleDecl>();

+        bindings = new Dictionary<string, ModuleBindings>();

+      }

+      public bool BindName(string name, ModuleDecl subModule, ModuleBindings b) {

+        if (modules.ContainsKey(name)) {

+          return false;

+        } else {

+          modules.Add(name, subModule);

+          bindings.Add(name, b);

+          return true;

+        }

+      }

+      public bool TryLookup(IToken name, out ModuleDecl m) {

+        Contract.Requires(name != null);

+        if (modules.TryGetValue(name.val, out m)) {

+          return true;

+        } else if (parent != null) {

+          return parent.TryLookup(name, out m);

+        } else return false;

+      }

+      public bool TryLookupLocal(IToken name, out ModuleDecl m) {

+        Contract.Requires(name != null);

+        if (modules.TryGetValue(name.val, out m)) {

+          return true;

+        } else return false;

+      }

+      public IEnumerable<ModuleDecl> ModuleList {

+        get { return modules.Values; }

+      }

+      public ModuleBindings SubBindings(string name) {

+        ModuleBindings v = null;

+        bindings.TryGetValue(name, out v);

+        return v;

+      }

+    }

+    private ModuleBindings BindModuleNames(ModuleDefinition moduleDecl, ModuleBindings parentBindings) {

+      var bindings = new ModuleBindings(parentBindings);

+

+      foreach (var tld in moduleDecl.TopLevelDecls) {

+        if (tld is LiteralModuleDecl) {

+          var subdecl = (LiteralModuleDecl)tld;

+          var subBindings = BindModuleNames(subdecl.ModuleDef, bindings);

+          if (!bindings.BindName(subdecl.Name, subdecl, subBindings)) {

+            Error(subdecl.Module, "Duplicate module name: {0}", subdecl.Name);

           }

-          // constructors:

-          foreach (var kv in import.Ctors) {

-            Tuple<DatatypeCtor, bool> pair;

-            if (info.Ctors.TryGetValue(kv.Key, out pair)) {

-              // mark it as a duplicate

-              info.Ctors[kv.Key] = new Tuple<DatatypeCtor, bool>(pair.Item1, true);

-            } else {

-              // add new

-              info.Ctors.Add(kv.Key, kv.Value);

-            }

+        } else if (tld is AbstractModuleDecl) {

+          var subdecl = (AbstractModuleDecl)tld;

+          if (!bindings.BindName(subdecl.Name, subdecl, null)) {

+            Error(subdecl.Module, "Duplicate module name: {0}", subdecl.Name);

+          }

+        } else if (tld is AliasModuleDecl) {

+          var subdecl = (AliasModuleDecl)tld;

+          if (!bindings.BindName(subdecl.Name, subdecl, null)) {

+            Error(subdecl.Module, "Duplicate module name: {0}", subdecl.Name);

           }

         }

-        // finally, for the module itself, let its information override whatever is imported

-        foreach (var kv in modules[m.Height].Classes) {

-          info.Classes[kv.Key] = kv.Value;

+      }

+      return bindings;

+    }

+

+    private void ProcessDependenciesDefinition(ModuleDecl decl, ModuleDefinition m, ModuleBindings bindings, Graph<ModuleDecl> dependencies) {

+      if (m.RefinementBaseName != null) {

+        ModuleDecl other;

+        if (!bindings.TryLookup(m.RefinementBaseName[0], out other)) {

+          Error(m, "module {0} named as refinement base does not exist", m.RefinementBaseName[0].val);

+        } else if (other is LiteralModuleDecl && ((LiteralModuleDecl)other).ModuleDef == m) {

+          Error(m, "module cannot refine itself: {0}", m.RefinementBaseName[0].val);

+        } else {

+          Contract.Assert(other != null);  // follows from postcondition of TryGetValue

+          dependencies.AddEdge(decl, other);

+          m.RefinementBaseRoot = other;

+        }

+      }

+      foreach (var toplevel in m.TopLevelDecls) {

+        if (toplevel is ModuleDecl) {

+          var d = (ModuleDecl)toplevel;

+          dependencies.AddEdge(decl, d);

+          var subbindings = bindings.SubBindings(d.Name);

+          ProcessDependencies(d, subbindings ?? bindings, dependencies);

         }

-        foreach (var kv in modules[m.Height].Ctors) {

-          info.Ctors[kv.Key] = kv.Value;

+      }

+    }

+    private void ProcessDependencies(ModuleDecl moduleDecl, ModuleBindings bindings, Graph<ModuleDecl> dependencies) {

+      dependencies.AddVertex(moduleDecl);

+      if (moduleDecl is LiteralModuleDecl) {

+        ProcessDependenciesDefinition(moduleDecl, ((LiteralModuleDecl)moduleDecl).ModuleDef, bindings, dependencies);

+      } else if (moduleDecl is AliasModuleDecl) {

+        var alias = moduleDecl as AliasModuleDecl;

+        ModuleDecl root;

+        if (!bindings.TryLookup(alias.Path[0], out root))

+          Error(alias.tok, "module {0} does not exist", Util.Comma(".", alias.Path, x => x.val));

+        else {

+          dependencies.AddEdge(moduleDecl, root);

+          alias.Root = root;

+        }

+      } else if (moduleDecl is AbstractModuleDecl) {

+        var abs = moduleDecl as AbstractModuleDecl;

+        ModuleDecl root;

+        if (!bindings.TryLookup(abs.Path[0], out root))

+          Error(abs.tok, "module {0} does not exist", Util.Comma(".", abs.Path, x => x.val));

+        else {

+          dependencies.AddEdge(moduleDecl, root);

+          abs.Root = root;

         }

-        return info;

       }

     }

 

-    ModuleNameInformation RegisterTopLevelDecls(List<TopLevelDecl> declarations) {

-      Contract.Requires(declarations != null);

-      var info = new ModuleNameInformation();

+    public static ModuleSignature MergeSignature(ModuleSignature m, ModuleSignature system) {

+      var info = new ModuleSignature();

+      // add the system-declared information, among which we know there are no duplicates

+      foreach (var kv in system.TopLevels) {

+        info.TopLevels.Add(kv.Key, kv.Value);

+      }

+      foreach (var kv in system.Ctors) {

+        info.Ctors.Add(kv.Key, kv.Value);

+      }

+      // add for the module itself

+      foreach (var kv in m.TopLevels) {

+        info.TopLevels[kv.Key] = kv.Value;

+      }

+      foreach (var kv in m.Ctors) {

+        info.Ctors[kv.Key] = kv.Value;

+      }

+      return info;

+    }

+    ModuleSignature RegisterTopLevelDecls(ModuleDefinition moduleDef) {

+      Contract.Requires(moduleDef != null);

+      var sig = new ModuleSignature();

+      sig.ModuleDef = moduleDef;

+      List<TopLevelDecl> declarations = moduleDef.TopLevelDecls;

 

       foreach (TopLevelDecl d in declarations) {

         Contract.Assert(d != null);

-        // register the class/datatype name

-        if (info.Classes.ContainsKey(d.Name)) {

+        // register the class/datatype/module name

+        if (sig.TopLevels.ContainsKey(d.Name)) {

           Error(d, "Duplicate name of top-level declaration: {0}", d.Name);

         } else {

-          info.Classes.Add(d.Name, d);

+          sig.TopLevels.Add(d.Name, d);

         }

-

-        if (d is ArbitraryTypeDecl) {

+        if (d is ModuleDecl) {

+          // nothing to do

+        } else if (d is ArbitraryTypeDecl) {

           // nothing more to register

 

         } else if (d is ClassDecl) {

@@ -334,12 +430,12 @@ namespace Microsoft.Dafny {
 

               // also register the constructor name globally

               Tuple<DatatypeCtor, bool> pair;

-              if (info.Ctors.TryGetValue(ctor.Name, out pair)) {

+              if (sig.Ctors.TryGetValue(ctor.Name, out pair)) {

                 // mark it as a duplicate

-                info.Ctors[ctor.Name] = new Tuple<DatatypeCtor, bool>(pair.Item1, true);

+                sig.Ctors[ctor.Name] = new Tuple<DatatypeCtor, bool>(pair.Item1, true);

               } else {

                 // add new

-                info.Ctors.Add(ctor.Name, new Tuple<DatatypeCtor, bool>(ctor, false));

+                sig.Ctors.Add(ctor.Name, new Tuple<DatatypeCtor, bool>(ctor, false));

               }

             }

           }

@@ -361,9 +457,333 @@ namespace Microsoft.Dafny {
           }

         }

       }

-      return info;

+      return sig;

+    }

+

+    private ModuleSignature MakeAbstractSignature(ModuleSignature p, string Name, int Height, out ModuleDefinition mod) {

+      mod = new ModuleDefinition(Token.NoToken, Name+".Abs", true, true, null, null);

+      mod.Height = Height;

+      foreach (var kv in p.TopLevels) {

+        mod.TopLevelDecls.Add(CloneDeclaration(kv.Value, mod));

+      }

+      var sig = RegisterTopLevelDecls(mod);

+      sig.Refines = p.Refines;

+      return sig;

+    }

+    TopLevelDecl CloneDeclaration(TopLevelDecl d, ModuleDefinition m) {

+      Contract.Requires(d != null);

+      Contract.Requires(m != null);

+

+      if (d is ArbitraryTypeDecl) {

+        var dd = (ArbitraryTypeDecl)d;

+        return new ArbitraryTypeDecl(dd.tok, dd.Name, m, dd.EqualitySupport, null);

+      } else if (d is IndDatatypeDecl) {

+        var dd = (IndDatatypeDecl)d;

+        var tps = dd.TypeArgs.ConvertAll(CloneTypeParam);

+        var ctors = dd.Ctors.ConvertAll(CloneCtor);

+        var dt = new IndDatatypeDecl(dd.tok, dd.Name, m, tps, ctors, null);

+        return dt;

+      } else if (d is CoDatatypeDecl) {

+        var dd = (CoDatatypeDecl)d;

+        var tps = dd.TypeArgs.ConvertAll(CloneTypeParam);

+        var ctors = dd.Ctors.ConvertAll(CloneCtor);

+        var dt = new CoDatatypeDecl(dd.tok, dd.Name, m, tps, ctors, null);

+        return dt;

+      } else if (d is ClassDecl) {

+        var dd = (ClassDecl)d;

+        var tps = dd.TypeArgs.ConvertAll(CloneTypeParam);

+        var mm = dd.Members.ConvertAll(CloneMember);

+        var cl = new ClassDecl(dd.tok, dd.Name, m, tps, mm, null);

+        return cl;

+      } else if (d is ModuleDecl) {

+        if (d is LiteralModuleDecl) {

+          return new LiteralModuleDecl(((LiteralModuleDecl)d).ModuleDef, m);

+        } else if (d is AliasModuleDecl) {

+          var a = (AliasModuleDecl)d;

+          var alias = new AliasModuleDecl(a.Path, a.tok, m);

+          alias.ModuleReference = a.ModuleReference;

+          alias.Signature = a.Signature;

+          return alias;

+        }

+        Contract.Assert(false);  // unexpected declaration

+        return null;  // to please compiler

+      } else {

+        Contract.Assert(false);  // unexpected declaration

+        return null;  // to please compiler

+      }

+    }

+    MemberDecl CloneMember(MemberDecl member) {

+      if (member is Field) {

+        var f = (Field)member;

+        return new Field(f.tok, f.Name, f.IsGhost, f.IsMutable, CloneType(f.Type), null);

+      } else if (member is Function) {

+        var f = (Function)member;

+        return CloneFunction(f.tok, f, f.IsGhost);

+      } else {

+        var m = (Method)member;

+        return CloneMethod(m);

+      }

+    }

+    TypeParameter CloneTypeParam(TypeParameter tp) {

+      return new TypeParameter(tp.tok, tp.Name);

+    }

+

+    DatatypeCtor CloneCtor(DatatypeCtor ct) {

+      return new DatatypeCtor(ct.tok, ct.Name, ct.Formals.ConvertAll(CloneFormal), null);

+    }

+    Formal CloneFormal(Formal formal) {

+      return new Formal(formal.tok, formal.Name, CloneType(formal.Type), formal.InParam, formal.IsGhost);

+    }

+    Type CloneType(Type t) {

+      if (t is BasicType) { 

+        return t;

+      } else if (t is SetType) {

+        var tt = (SetType)t;

+        return new SetType(CloneType(tt.Arg));

+      } else if (t is SeqType) {

+        var tt = (SeqType)t;

+        return new SeqType(CloneType(tt.Arg));

+      } else if (t is MultiSetType) {

+        var tt = (MultiSetType)t;

+        return new MultiSetType(CloneType(tt.Arg));

+      } else if (t is MapType) {

+        var tt = (MapType)t;

+        return new MapType(CloneType(tt.Domain), CloneType(tt.Range));

+      } else if (t is UserDefinedType) {

+        var tt = (UserDefinedType)t;

+        return new UserDefinedType(tt.tok, tt.Name, tt.TypeArgs.ConvertAll(CloneType), tt.ModuleName == null ? null : tt.ModuleName);

+      } else if (t is InferredTypeProxy) {

+        return new InferredTypeProxy();

+      } else {

+        Contract.Assert(false);  // unexpected type (e.g., no other type proxies are expected at this time)

+        return null;  // to please compiler

+      }

+    }

+    Function CloneFunction(IToken tok, Function f, bool isGhost) {

+

+      var tps = f.TypeArgs.ConvertAll(CloneTypeParam);

+      var formals = f.Formals.ConvertAll(CloneFormal);

+      var req = f.Req.ConvertAll(CloneExpr);

+      var reads = f.Reads.ConvertAll(CloneFrameExpr);

+      var decreases = CloneSpecExpr(f.Decreases);

+

+      var ens = f.Ens.ConvertAll(CloneExpr);

+

+      Expression body = CloneExpr(f.Body);

+      

+      if (f is Predicate) {

+        return new Predicate(tok, f.Name, f.IsStatic, isGhost, tps, f.OpenParen, formals,

+          req, reads, ens, decreases, body, false, null, false);

+      } else {

+        return new Function(tok, f.Name, f.IsStatic, isGhost, tps, f.OpenParen, formals, CloneType(f.ResultType),

+          req, reads, ens, decreases, body, null, false);

+      }

+    }

+    Method CloneMethod(Method m) {

+      Contract.Requires(m != null);

+

+      var tps = m.TypeArgs.ConvertAll(CloneTypeParam);

+      var ins = m.Ins.ConvertAll(CloneFormal);

+      var req = m.Req.ConvertAll(CloneMayBeFreeExpr);

+      var mod = CloneSpecFrameExpr(m.Mod);

+      var decreases = CloneSpecExpr(m.Decreases);

+

+      var ens = m.Ens.ConvertAll(CloneMayBeFreeExpr);

+      

+      if (m is Constructor) {

+        return new Constructor(m.tok, m.Name, tps, ins,

+          req, mod, ens, decreases, null, null, false);

+      } else {

+        return new Method(m.tok, m.Name, m.IsStatic, m.IsGhost, tps, ins, m.Outs.ConvertAll(CloneFormal),

+          req, mod, ens, decreases, null, null, false);

+      }

+    }

+    Specification<Expression> CloneSpecExpr(Specification<Expression> spec) {

+      var ee = spec.Expressions == null ? null : spec.Expressions.ConvertAll(CloneExpr);

+      return new Specification<Expression>(ee, null);

+    }

+    Specification<FrameExpression> CloneSpecFrameExpr(Specification<FrameExpression> frame) {

+      var ee = frame.Expressions == null ? null : frame.Expressions.ConvertAll(CloneFrameExpr);

+      return new Specification<FrameExpression>(ee, null);

+    }

+    FrameExpression CloneFrameExpr(FrameExpression frame) {

+      return new FrameExpression(CloneExpr(frame.E), frame.FieldName);

+    }

+    MaybeFreeExpression CloneMayBeFreeExpr(MaybeFreeExpression expr) {

+      return new MaybeFreeExpression(CloneExpr(expr.E), expr.IsFree);

     }

+    BoundVar CloneBoundVar(BoundVar bv) {

+      return new BoundVar((bv.tok), bv.Name, CloneType(bv.Type));

+    }

+    Expression CloneExpr(Expression expr) {

+      if (expr == null) {

+        return null;

+      } else if (expr is LiteralExpr) {

+        var e = (LiteralExpr)expr;

+        if (e.Value == null) {

+          return new LiteralExpr((e.tok));

+        } else if (e.Value is bool) {

+          return new LiteralExpr((e.tok), (bool)e.Value);

+        } else {

+          return new LiteralExpr((e.tok), (BigInteger)e.Value);

+        }

+

+      } else if (expr is ThisExpr) {

+        if (expr is ImplicitThisExpr) {

+          return new ImplicitThisExpr((expr.tok));

+        } else {

+          return new ThisExpr((expr.tok));

+        }

+

+      } else if (expr is IdentifierExpr) {

+        var e = (IdentifierExpr)expr;

+        return new IdentifierExpr((e.tok), e.Name);

+

+      } else if (expr is DatatypeValue) {

+        var e = (DatatypeValue)expr;

+        return new DatatypeValue((e.tok), e.DatatypeName, e.MemberName, e.Arguments.ConvertAll(CloneExpr));

+

+      } else if (expr is DisplayExpression) {

+        DisplayExpression e = (DisplayExpression)expr;

+        if (expr is SetDisplayExpr) {

+          return new SetDisplayExpr((e.tok), e.Elements.ConvertAll(CloneExpr));

+        } else if (expr is MultiSetDisplayExpr) {

+          return new MultiSetDisplayExpr((e.tok), e.Elements.ConvertAll(CloneExpr));

+        } else {

+          Contract.Assert(expr is SeqDisplayExpr);

+          return new SeqDisplayExpr((e.tok), e.Elements.ConvertAll(CloneExpr));

+        }

 

+      } else if (expr is MapDisplayExpr) {

+        MapDisplayExpr e = (MapDisplayExpr)expr;

+        List<ExpressionPair> pp = new List<ExpressionPair>();

+        foreach (ExpressionPair p in e.Elements) {

+          pp.Add(new ExpressionPair(CloneExpr(p.A), CloneExpr(p.B)));

+        }

+        return new MapDisplayExpr((expr.tok), pp);

+      } else if (expr is ExprDotName) {

+        var e = (ExprDotName)expr;

+        return new ExprDotName((e.tok), CloneExpr(e.Obj), e.SuffixName);

+

+      } else if (expr is FieldSelectExpr) {

+        var e = (FieldSelectExpr)expr;

+        return new FieldSelectExpr((e.tok), CloneExpr(e.Obj), e.FieldName);

+

+      } else if (expr is SeqSelectExpr) {

+        var e = (SeqSelectExpr)expr;

+        return new SeqSelectExpr((e.tok), e.SelectOne, CloneExpr(e.Seq), CloneExpr(e.E0), CloneExpr(e.E1));

+

+      } else if (expr is MultiSelectExpr) {

+        var e = (MultiSelectExpr)expr;

+        return new MultiSelectExpr((e.tok), CloneExpr(e.Array), e.Indices.ConvertAll(CloneExpr));

+

+      } else if (expr is SeqUpdateExpr) {

+        var e = (SeqUpdateExpr)expr;

+        return new SeqUpdateExpr((e.tok), CloneExpr(e.Seq), CloneExpr(e.Index), CloneExpr(e.Value));

+

+      } else if (expr is FunctionCallExpr) {

+        var e = (FunctionCallExpr)expr;

+        return new FunctionCallExpr((e.tok), e.Name, CloneExpr(e.Receiver), e.OpenParen == null ? null : (e.OpenParen), e.Args.ConvertAll(CloneExpr));

+

+      } else if (expr is OldExpr) {

+        var e = (OldExpr)expr;

+        return new OldExpr((e.tok), CloneExpr(e.E));

+

+      } else if (expr is MultiSetFormingExpr) {

+        var e = (MultiSetFormingExpr)expr;

+        return new MultiSetFormingExpr((e.tok), CloneExpr(e.E));

+

+      } else if (expr is FreshExpr) {

+        var e = (FreshExpr)expr;

+        return new FreshExpr((e.tok), CloneExpr(e.E));

+

+      } else if (expr is AllocatedExpr) {

+        var e = (AllocatedExpr)expr;

+        return new AllocatedExpr((e.tok), CloneExpr(e.E));

+

+      } else if (expr is UnaryExpr) {

+        var e = (UnaryExpr)expr;

+        return new UnaryExpr((e.tok), e.Op, CloneExpr(e.E));

+

+      } else if (expr is BinaryExpr) {

+        var e = (BinaryExpr)expr;

+        return new BinaryExpr((e.tok), e.Op, CloneExpr(e.E0), CloneExpr(e.E1));

+

+      } else if (expr is ChainingExpression) {

+        var e = (ChainingExpression)expr;

+        return CloneExpr(e.E);  // just clone the desugaring, since it's already available

+

+      } else if (expr is LetExpr) {

+        var e = (LetExpr)expr;

+        return new LetExpr((e.tok), e.Vars.ConvertAll(CloneBoundVar), e.RHSs.ConvertAll(CloneExpr), CloneExpr(e.Body));

+

+      } else if (expr is ComprehensionExpr) {

+        var e = (ComprehensionExpr)expr;

+        var tk = (e.tok);

+        var bvs = e.BoundVars.ConvertAll(CloneBoundVar);

+        var range = CloneExpr(e.Range);

+        var term = CloneExpr(e.Term);

+        if (e is ForallExpr) {

+          return new ForallExpr(tk, bvs, range, term, null);

+        } else if (e is ExistsExpr) {

+          return new ExistsExpr(tk, bvs, range, term, null);

+        } else if (e is MapComprehension) {

+          return new MapComprehension(tk, bvs, range, term);

+        } else {

+          Contract.Assert(e is SetComprehension);

+          return new SetComprehension(tk, bvs, range, term);

+        }

+

+      } else if (expr is WildcardExpr) {

+        return new WildcardExpr((expr.tok));

+

+      } else if (expr is PredicateExpr) {

+        var e = (PredicateExpr)expr;

+        if (e is AssertExpr) {

+          return new AssertExpr((e.tok), CloneExpr(e.Guard), CloneExpr(e.Body));

+        } else {

+          Contract.Assert(e is AssumeExpr);

+          return new AssumeExpr((e.tok), CloneExpr(e.Guard), CloneExpr(e.Body));

+        }

+

+      } else if (expr is ITEExpr) {

+        var e = (ITEExpr)expr;

+        return new ITEExpr((e.tok), CloneExpr(e.Test), CloneExpr(e.Thn), CloneExpr(e.Els));

+

+      } else if (expr is ParensExpression) {

+        var e = (ParensExpression)expr;

+        return CloneExpr(e.E);  // skip the parentheses in the clone

+

+      } else if (expr is IdentifierSequence) {

+        var e = (IdentifierSequence)expr;

+        var aa = e.Arguments == null ? null : e.Arguments.ConvertAll(CloneExpr);

+        return new IdentifierSequence(e.Tokens.ConvertAll(tk => (tk)), e.OpenParen == null ? null : (e.OpenParen), aa);

+

+      } else if (expr is MatchExpr) {

+        var e = (MatchExpr)expr;

+        return new MatchExpr((e.tok), CloneExpr(e.Source),

+          e.Cases.ConvertAll(c => new MatchCaseExpr((c.tok), c.Id, c.Arguments.ConvertAll(CloneBoundVar), CloneExpr(c.Body))));

+

+      } else {

+        Contract.Assert(false); throw new cce.UnreachableException();  // unexpected expression

+      }

+    }

+

+    private bool ResolvePath(ModuleDecl root, List<IToken> Path, out ModuleSignature p) {

+      p = root.Signature;

+      int i = 1;

+      while (i < Path.Count) {

+        ModuleSignature pp;

+        if (p.FindSubmodule(Path[i].val, out pp)) {

+          p = pp;

+          i++;

+        } else {

+          Error(Path[i], "module {0} does not exist", Path[i].val);

+          break;

+        }

+      }

+      return i == Path.Count;

+    }

     public void ResolveTopLevelDecls_Signatures(List<TopLevelDecl/*!*/>/*!*/ declarations, Graph<IndDatatypeDecl/*!*/>/*!*/ datatypeDependencies) {

       Contract.Requires(declarations != null);

       Contract.Requires(datatypeDependencies != null);  // more expensive check: Contract.Requires(cce.NonNullElements(datatypeDependencies));

@@ -375,6 +795,8 @@ namespace Microsoft.Dafny {
           // nothing to do

         } else if (d is ClassDecl) {

           ResolveClassMemberTypes((ClassDecl)d);

+        } else if (d is ModuleDecl) {

+          // TODO: what goes here?

         } else {

           ResolveCtorTypes((DatatypeDecl)d, datatypeDependencies);

         }

@@ -831,6 +1253,7 @@ namespace Microsoft.Dafny {
     Scope<Statement>/*!*/ labeledStatements = new Scope<Statement>();

     List<Statement> loopStack = new List<Statement>();  // the enclosing loops (from which it is possible to break out)

     readonly Dictionary<Statement, bool> inSpecOnlyContext = new Dictionary<Statement, bool>();  // invariant: domain contain union of the domains of "labeledStatements" and "loopStack"

+    

 

     /// <summary>

     /// Assumes type parameters have already been pushed

@@ -1435,23 +1858,15 @@ namespace Microsoft.Dafny {
         } else if (t.ResolvedClass == null) {  // this test is because 'array' is already resolved; TODO: an alternative would be to pre-populate 'classes' with built-in references types like 'array' (and perhaps in the future 'string')

           TopLevelDecl d = null;

           if (t.ModuleName != null) {

-            foreach (var imp in currentClass.Module.Imports) {

-              if (imp.Name == t.ModuleName.val) {

-                // now search among the types declared in module "imp"

-                foreach (var tld in imp.TopLevelDecls) {  // this search is slow, but oh well

-                  if (tld.Name == t.Name) {

-                    // found the class

-                    d = tld;

-                    goto DONE_WITH_QUALIFIED_NAME;

-                  }

-                }

-                Error(t.tok, "Undeclared class name {0} in module {1}", t.Name, t.ModuleName.val);

-                goto DONE_WITH_QUALIFIED_NAME;

+            ModuleSignature sig;

+            if (moduleInfo.FindSubmodule(t.ModuleName.val, out sig)) {

+              if (!sig.TopLevels.TryGetValue(t.Name, out d)) {

+                Error(t.tok, "The name does not exist in the given module");

               }

+            } else {

+              Error(t.ModuleName, "Undeclared module name: {0} (did you forget a module import?)", t.ModuleName.val);

             }

-            Error(t.ModuleName, "Undeclared module name: {0} (did you forget a module import?)", t.ModuleName.val);

-          DONE_WITH_QUALIFIED_NAME: ;

-          } else if (!classes.TryGetValue(t.Name, out d)) {

+          } else if (!moduleInfo.TopLevels.TryGetValue(t.Name, out d)) {

             Error(t.tok, "Undeclared top-level type or type parameter: {0} (did you forget a module import?)", t.Name);

           }

 

@@ -2627,13 +3042,14 @@ namespace Microsoft.Dafny {
 

         // Resolution termination check

         if (method.EnclosingClass != null && callee.EnclosingClass != null) {

-          ModuleDecl callerModule = method.EnclosingClass.Module;

-          ModuleDecl calleeModule = callee.EnclosingClass.Module;

+          ModuleDefinition callerModule = method.EnclosingClass.Module;

+          ModuleDefinition calleeModule = callee.EnclosingClass.Module;

           if (callerModule == calleeModule) {

             // intra-module call; this is allowed; add edge in module's call graph

             callerModule.CallGraph.AddEdge(method, callee);

           } else {

-            Contract.Assert(importGraph.Reaches(callerModule, calleeModule));

+            //Contract.Assert(dependencies.Reaches(callerModule, calleeModule));

+            //

           }

         }

       }

@@ -3067,7 +3483,7 @@ namespace Microsoft.Dafny {
       } else if (expr is DatatypeValue) {

         DatatypeValue dtv = (DatatypeValue)expr;

         TopLevelDecl d;

-        if (!classes.TryGetValue(dtv.DatatypeName, out d)) {

+        if (!moduleInfo.TopLevels.TryGetValue(dtv.DatatypeName, out d)) {

           Error(expr.tok, "Undeclared datatype: {0}", dtv.DatatypeName);

         } else if (d is AmbiguousTopLevelDecl) {

           Error(expr.tok, "The name {0} ambiguously refers to a type in one of the modules {1}", dtv.DatatypeName, ((AmbiguousTopLevelDecl)d).ModuleNames());

@@ -3345,7 +3761,7 @@ namespace Microsoft.Dafny {
 

           case BinaryExpr.Opcode.Eq:

           case BinaryExpr.Opcode.Neq:

-            if (!CouldPossiblyBeSameType(e.E0.Type, e.E1.Type)) {

+            if (!ComparableTypes(e.E0.Type, e.E1.Type)) {

               if (!UnifyTypes(e.E0.Type, e.E1.Type)) {

                 Error(expr, "arguments must have the same type (got {0} and {1})", e.E0.Type, e.E1.Type);

               }

@@ -3740,6 +4156,31 @@ namespace Microsoft.Dafny {
       }

     }

 

+    private bool ComparableTypes(Type A, Type B) {

+      if (A.IsArrayType && B.IsArrayType) {

+        Type a = UserDefinedType.ArrayElementType(A);

+        Type b = UserDefinedType.ArrayElementType(B);

+        return CouldPossiblyBeSameType(a, b);

+      } else 

+      if (A is UserDefinedType && B is UserDefinedType) {

+        UserDefinedType a = (UserDefinedType)A;

+        UserDefinedType b = (UserDefinedType)B;

+        if (a.ResolvedClass != null && b.ResolvedClass != null && a.ResolvedClass.Name == b.ResolvedClass.Name) {

+          if (a.TypeArgs.Count != b.TypeArgs.Count) {

+            return false; // this probably doesn't happen if the classes are the same.

+          }

+          for (int i = 0; i < a.TypeArgs.Count; i++) {

+            if (!CouldPossiblyBeSameType(a.TypeArgs[i], b.TypeArgs[i]))

+              return false;

+          }

+          // all parameters could be the same

+          return true;

+        }

+        // either we don't know what class it is yet, or the classes mismatch

+        return false;

+      }

+      return false;

+    }

     private bool CouldPossiblyBeSameType(Type A, Type B) {

       if (A.IsTypeParameter || B.IsTypeParameter) {

         return true;

@@ -3934,8 +4375,8 @@ namespace Microsoft.Dafny {
 

         // Resolution termination check

         if (currentFunction != null && currentFunction.EnclosingClass != null && function.EnclosingClass != null) {

-          ModuleDecl callerModule = currentFunction.EnclosingClass.Module;

-          ModuleDecl calleeModule = function.EnclosingClass.Module;

+          ModuleDefinition callerModule = currentFunction.EnclosingClass.Module;

+          ModuleDefinition calleeModule = function.EnclosingClass.Module;

           if (callerModule == calleeModule) {

             // intra-module call; this is allowed; add edge in module's call graph

             callerModule.CallGraph.AddEdge(currentFunction, function);

@@ -3943,7 +4384,7 @@ namespace Microsoft.Dafny {
               currentFunction.IsRecursive = true;  // self recursion (mutual recursion is determined elsewhere)

             }

           } else {

-            Contract.Assert(importGraph.Reaches(callerModule, calleeModule));

+            //Contract.Assert(dependencies.Reaches(callerModule, calleeModule));

           }

         }

       }

@@ -3957,9 +4398,11 @@ namespace Microsoft.Dafny {
     CallRhs ResolveIdentifierSequence(IdentifierSequence e, bool twoState, bool allowMethodCall) {

       // Look up "id" as follows:

       //  - local variable, parameter, or bound variable (if this clashes with something of interest, one can always rename the local variable locally)

-      //  - unamibugous type name (class or datatype or arbitrary-type) (if two imported types have the same name, an error message is produced here)

+      //  - unamibugous type/module name (class, datatype, sub-module (including submodules of imports) or arbitrary-type)

+      //       (if two imported types have the same name, an error message is produced here)

       //  - unambiguous constructor name of a datatype (if two constructors have the same name, an error message is produced here)

-      //  - field name (with implicit receiver) (if the field is ocluded by anything above, one can use an explicit "this.")

+      //  - imported module name

+      //  - field name (with implicit receiver) (if the field is occluded by anything above, one can use an explicit "this.")

       // Note, at present, modules do not give rise to new namespaces, which is something that should

       // be changed in the language when modules are given more attention.

       Expression r = null;  // resolved version of e

@@ -3976,7 +4419,7 @@ namespace Microsoft.Dafny {
         ResolveExpression(r, twoState);

         r = ResolveSuffix(r, e, 1, twoState, allowMethodCall, out call);

 

-      } else if (classes.TryGetValue(id.val, out decl)) {

+      } else if (moduleInfo.TopLevels.TryGetValue(id.val, out decl)) {

         if (decl is AmbiguousTopLevelDecl) {

           Error(id, "The name {0} ambiguously refers to a type in one of the modules {1}", id.val, ((AmbiguousTopLevelDecl)decl).ModuleNames());

         } else  if (e.Tokens.Count == 1 && e.Arguments == null) {

@@ -3992,6 +4435,12 @@ namespace Microsoft.Dafny {
           var cd = (ClassDecl)decl;

           r = ResolveSuffix(new StaticReceiverExpr(id, cd), e, 1, twoState, allowMethodCall, out call);

 

+        } else if (decl is ModuleDecl) {

+          // ----- root is a submodule

+          if (!(1 < e.Tokens.Count)) {

+            Error(e.tok, "module {0} cannot be used here", ((ModuleDecl)decl).Name);

+          }

+          call = ResolveIdentifierSequenceModuleScope(e, 1, ((ModuleDecl)decl).Signature, twoState, allowMethodCall);

         } else {

           // ----- root is a datatype

           var dt = (DatatypeDecl)decl;  // otherwise, unexpected TopLevelDecl

@@ -4003,7 +4452,7 @@ namespace Microsoft.Dafny {
           }

         }

 

-      } else if (allDatatypeCtors.TryGetValue(id.val, out pair)) {

+      } else if (moduleInfo.Ctors.TryGetValue(id.val, out pair)) {

         // ----- root is a datatype constructor

         if (pair.Item2) {

           // there is more than one constructor with this name

@@ -4049,6 +4498,59 @@ namespace Microsoft.Dafny {
       return call;

     }

 

+    CallRhs ResolveIdentifierSequenceModuleScope(IdentifierSequence e, int p, ModuleSignature info, bool twoState, bool allowMethodCall) {

+      // Look up "id" as follows:

+      //  - unamibugous type/module name (class, datatype, sub-module (including submodules of imports) or arbitrary-type)

+      //       (if two imported types have the same name, an error message is produced here)

+      // This is used to look up names that appear after a dot in a sequence identifier. For example, in X.M.*, M should be looked up in X, but

+      // should not consult the local scope. This distingushes this from the above, in that local scope, imported modules, etc. are ignored.

+      Contract.Requires(p < e.Tokens.Count);

+      Expression r = null;  // resolved version of e

+      CallRhs call = null;

+

+      TopLevelDecl decl;

+      var id = e.Tokens[p];

+      if (info.TopLevels.TryGetValue(id.val, out decl)) {

+        if (decl is AmbiguousTopLevelDecl) {

+          Error(id, "The name {0} ambiguously refers to a something in one of the modules {1}", id.val, ((AmbiguousTopLevelDecl)decl).ModuleNames());

+        } else if (decl is ClassDecl) {

+          // ----- root is a class

+          var cd = (ClassDecl)decl;

+          r = ResolveSuffix(new StaticReceiverExpr(id, cd), e, p + 1, twoState, allowMethodCall, out call);

+

+        } else if (decl is ModuleDecl) {

+          // ----- root is a submodule

+          if (!(p + 1 < e.Tokens.Count)) {

+            Error(e.tok, "module {0} cannot be used here", ((ModuleDecl)decl).Name);

+          }

+          call = ResolveIdentifierSequenceModuleScope(e, p + 1, ((ModuleDecl)decl).Signature, twoState, allowMethodCall);

+        } else {

+          // ----- root is a datatype

+          var dt = (DatatypeDecl)decl;  // otherwise, unexpected TopLevelDecl

+          var args = (e.Tokens.Count == p + 2 ? e.Arguments : null) ?? new List<Expression>();

+          r = new DatatypeValue(id, id.val, e.Tokens[p + 1].val, args);

+          ResolveExpression(r, twoState);

+          if (e.Tokens.Count != p + 2) {

+            r = ResolveSuffix(r, e, p + 2, twoState, allowMethodCall, out call);

+          }

+        }

+      } else {

+        Error(id, "unresolved identifier: {0}", id.val);

+        // resolve arguments, if any

+        if (e.Arguments != null) {

+          foreach (var arg in e.Arguments) {

+            ResolveExpression(arg, twoState);

+          }

+        }

+      }

+

+      if (r != null) {

+        e.ResolvedExpression = r;

+        e.Type = r.Type;

+      }

+      return call;

+    }

+

     /// <summary>

     /// Given resolved expression "r" and unresolved expressions e.Tokens[p..] and e.Arguments.

     /// Returns a resolved version of the expression:

@@ -4837,7 +5339,7 @@ namespace Microsoft.Dafny {
 

   class CoCallResolution

   {

-    readonly ModuleDecl currentModule;

+    readonly ModuleDefinition currentModule;

     readonly Function currentFunction;

     readonly bool dealsWithCodatatypes;

 

diff --git a/Source/Dafny/Rewriter.cs b/Source/Dafny/Rewriter.cs
index e04c5e9b..af41a679 100644
--- a/Source/Dafny/Rewriter.cs
+++ b/Source/Dafny/Rewriter.cs
@@ -7,16 +7,16 @@ namespace Microsoft.Dafny
   [ContractClass(typeof(IRewriterContracts))]

   public interface IRewriter

   {

-    void PreResolve(ModuleDecl m);

-    void PostResolve(ModuleDecl m);

+    void PreResolve(ModuleDefinition m);

+    void PostResolve(ModuleDefinition m);

   }

   [ContractClassFor(typeof(IRewriter))]

   abstract class IRewriterContracts : IRewriter

   {

-    public void PreResolve(ModuleDecl m) {

+    public void PreResolve(ModuleDefinition m) {

       Contract.Requires(m != null);

     }

-    public void PostResolve(ModuleDecl m) {

+    public void PostResolve(ModuleDefinition m) {

       Contract.Requires(m != null);

     }

   }

@@ -61,7 +61,7 @@ namespace Microsoft.Dafny
   /// </summary>

   public class AutoContractsRewriter : IRewriter

   {

-    public void PreResolve(ModuleDecl m) {

+    public void PreResolve(ModuleDefinition m) {

       foreach (var d in m.TopLevelDecls) {

         bool sayYes = true;

         if (d is ClassDecl && Attributes.ContainsBool(d.Attributes, "autocontracts", ref sayYes) && sayYes) {

@@ -112,7 +112,7 @@ namespace Microsoft.Dafny
       }

     }

 

-    public void PostResolve(ModuleDecl m) {

+    public void PostResolve(ModuleDefinition m) {

       foreach (var d in m.TopLevelDecls) {

         bool sayYes = true;

         if (d is ClassDecl && Attributes.ContainsBool(d.Attributes, "autocontracts", ref sayYes) && sayYes) {

diff --git a/Source/Dafny/Scanner.cs b/Source/Dafny/Scanner.cs
index 7cb302fa..32c92a8b 100644
--- a/Source/Dafny/Scanner.cs
+++ b/Source/Dafny/Scanner.cs
@@ -262,14 +262,14 @@ public class Scanner {
 		start[123] = 10; 

 		start[125] = 11; 

 		start[61] = 57; 

-		start[124] = 58; 

 		start[59] = 19; 

+		start[46] = 58; 

+		start[124] = 59; 

 		start[44] = 20; 

 		start[40] = 21; 

 		start[41] = 22; 

-		start[60] = 59; 

-		start[62] = 60; 

-		start[46] = 61; 

+		start[60] = 60; 

+		start[62] = 61; 

 		start[42] = 24; 

 		start[96] = 25; 

 		start[91] = 28; 

@@ -491,29 +491,29 @@ public class Scanner {
 			case "ghost": t.kind = 8; break;

 			case "module": t.kind = 9; break;

 			case "refines": t.kind = 10; break;

-			case "imports": t.kind = 11; break;

-			case "class": t.kind = 12; break;

-			case "static": t.kind = 13; break;

-			case "datatype": t.kind = 14; break;

-			case "codatatype": t.kind = 15; break;

-			case "var": t.kind = 19; break;

-			case "type": t.kind = 21; break;

-			case "method": t.kind = 27; break;

-			case "constructor": t.kind = 28; break;

-			case "returns": t.kind = 29; break;

-			case "modifies": t.kind = 31; break;

-			case "free": t.kind = 32; break;

-			case "requires": t.kind = 33; break;

-			case "ensures": t.kind = 34; break;

-			case "decreases": t.kind = 35; break;

-			case "bool": t.kind = 36; break;

-			case "nat": t.kind = 37; break;

-			case "int": t.kind = 38; break;

-			case "set": t.kind = 39; break;

-			case "multiset": t.kind = 40; break;

-			case "seq": t.kind = 41; break;

-			case "map": t.kind = 42; break;

-			case "object": t.kind = 43; break;

+			case "as": t.kind = 13; break;

+			case "class": t.kind = 15; break;

+			case "static": t.kind = 16; break;

+			case "datatype": t.kind = 17; break;

+			case "codatatype": t.kind = 18; break;

+			case "var": t.kind = 20; break;

+			case "type": t.kind = 22; break;

+			case "method": t.kind = 28; break;

+			case "constructor": t.kind = 29; break;

+			case "returns": t.kind = 30; break;

+			case "modifies": t.kind = 32; break;

+			case "free": t.kind = 33; break;

+			case "requires": t.kind = 34; break;

+			case "ensures": t.kind = 35; break;

+			case "decreases": t.kind = 36; break;

+			case "bool": t.kind = 37; break;

+			case "nat": t.kind = 38; break;

+			case "int": t.kind = 39; break;

+			case "set": t.kind = 40; break;

+			case "multiset": t.kind = 41; break;

+			case "seq": t.kind = 42; break;

+			case "map": t.kind = 43; break;

+			case "object": t.kind = 44; break;

 			case "function": t.kind = 45; break;

 			case "predicate": t.kind = 46; break;

 			case "reads": t.kind = 47; break;

@@ -648,15 +648,15 @@ public class Scanner {
 				else if (ch >= '0' && ch <= '9') {AddCh(); goto case 18;}

 				else {t.kind = 3; break;}

 			case 19:

-				{t.kind = 18; break;}

+				{t.kind = 12; break;}

 			case 20:

-				{t.kind = 20; break;}

+				{t.kind = 21; break;}

 			case 21:

-				{t.kind = 22; break;}

+				{t.kind = 23; break;}

 			case 22:

-				{t.kind = 24; break;}

+				{t.kind = 25; break;}

 			case 23:

-				{t.kind = 30; break;}

+				{t.kind = 31; break;}

 			case 24:

 				{t.kind = 48; break;}

 			case 25:

@@ -730,43 +730,43 @@ public class Scanner {
 				else if (ch == ':') {AddCh(); goto case 54;}

 				else {t.kind = 5; break;}

 			case 57:

-				recEnd = pos; recKind = 16;

+				recEnd = pos; recKind = 11;

 				if (ch == '=') {AddCh(); goto case 63;}

 				else if (ch == '>') {AddCh(); goto case 30;}

-				else {t.kind = 16; break;}

+				else {t.kind = 11; break;}

 			case 58:

-				recEnd = pos; recKind = 17;

-				if (ch == '|') {AddCh(); goto case 39;}

-				else {t.kind = 17; break;}

+				recEnd = pos; recKind = 14;

+				if (ch == '.') {AddCh(); goto case 64;}

+				else {t.kind = 14; break;}

 			case 59:

-				recEnd = pos; recKind = 25;

-				if (ch == '=') {AddCh(); goto case 64;}

-				else {t.kind = 25; break;}

+				recEnd = pos; recKind = 19;

+				if (ch == '|') {AddCh(); goto case 39;}

+				else {t.kind = 19; break;}

 			case 60:

 				recEnd = pos; recKind = 26;

-				if (ch == '=') {AddCh(); goto case 41;}

+				if (ch == '=') {AddCh(); goto case 65;}

 				else {t.kind = 26; break;}

 			case 61:

-				recEnd = pos; recKind = 44;

-				if (ch == '.') {AddCh(); goto case 65;}

-				else {t.kind = 44; break;}

+				recEnd = pos; recKind = 27;

+				if (ch == '=') {AddCh(); goto case 41;}

+				else {t.kind = 27; break;}

 			case 62:

 				recEnd = pos; recKind = 83;

 				if (ch == '=') {AddCh(); goto case 42;}

 				else if (ch == '!') {AddCh(); goto case 43;}

 				else {t.kind = 83; break;}

 			case 63:

-				recEnd = pos; recKind = 23;

+				recEnd = pos; recKind = 24;

 				if (ch == '>') {AddCh(); goto case 34;}

-				else {t.kind = 23; break;}

+				else {t.kind = 24; break;}

 			case 64:

-				recEnd = pos; recKind = 78;

-				if (ch == '=') {AddCh(); goto case 31;}

-				else {t.kind = 78; break;}

-			case 65:

 				recEnd = pos; recKind = 100;

 				if (ch == '.') {AddCh(); goto case 23;}

 				else {t.kind = 100; break;}

+			case 65:

+				recEnd = pos; recKind = 78;

+				if (ch == '=') {AddCh(); goto case 31;}

+				else {t.kind = 78; break;}

 

 		}

 		t.val = new String(tval, 0, tlen);

diff --git a/Source/Dafny/Translator.cs b/Source/Dafny/Translator.cs
index 1290f3ad..75a1e174 100644
--- a/Source/Dafny/Translator.cs
+++ b/Source/Dafny/Translator.cs
@@ -26,6 +26,7 @@ namespace Microsoft.Dafny {
     readonly Dictionary<TopLevelDecl/*!*/,Bpl.Constant/*!*/>/*!*/ classes = new Dictionary<TopLevelDecl/*!*/,Bpl.Constant/*!*/>();

     readonly Dictionary<Field/*!*/,Bpl.Constant/*!*/>/*!*/ fields = new Dictionary<Field/*!*/,Bpl.Constant/*!*/>();

     readonly Dictionary<Field/*!*/, Bpl.Function/*!*/>/*!*/ fieldFunctions = new Dictionary<Field/*!*/, Bpl.Function/*!*/>();

+    Program program;

 

     [ContractInvariantMethod]

     void ObjectInvariant()

@@ -306,9 +307,10 @@ namespace Microsoft.Dafny {
 */

     }

 

-    public Bpl.Program Translate(Program program) {

-      Contract.Requires(program != null);

+    public Bpl.Program Translate(Program p) {

+      Contract.Requires(p != null);

       Contract.Ensures(Contract.Result<Bpl.Program>() != null);

+      program = p;

 

       if (sink == null || predef == null) {

         // something went wrong during construction, which reads the prelude; an error has

@@ -325,14 +327,18 @@ namespace Microsoft.Dafny {
           AddClassMembers((ClassDecl)d);

         }

       }

-      foreach (ModuleDecl m in program.Modules) {

+      foreach (ModuleDefinition m in program.Modules) {

         foreach (TopLevelDecl d in m.TopLevelDecls) {

           if (d is ArbitraryTypeDecl) {

             // nothing to do--this is treated just like a type parameter

           } else if (d is DatatypeDecl) {

             AddDatatype((DatatypeDecl)d);

-          } else {

+          } else if (d is ClassDecl) {

             AddClassMembers((ClassDecl)d);

+          } else if (d is ModuleDecl) {

+            // nop, sub-modules are handled in their own iteration.

+          } else {

+            Contract.Assert(false);

           }

         }

       }

@@ -811,7 +817,7 @@ namespace Microsoft.Dafny {
       }

 

       // mh < ModuleContextHeight || (mh == ModuleContextHeight && (fh <= FunctionContextHeight || InMethodContext))

-      ModuleDecl mod = f.EnclosingClass.Module;

+      ModuleDefinition mod = f.EnclosingClass.Module;

       var activateForeign = Bpl.Expr.Lt(Bpl.Expr.Literal(mod.Height), etran.ModuleContextHeight());

       var activateIntra = 

         Bpl.Expr.And(

@@ -1017,7 +1023,7 @@ namespace Microsoft.Dafny {
       return Bpl.Expr.And(lower, upper);

     }

 

-    ModuleDecl currentModule = null;  // the name of the module whose members are currently being translated

+    ModuleDefinition currentModule = null;  // the name of the module whose members are currently being translated

     Method currentMethod = null;  // the method whose implementation is currently being translated

     int loopHeapVarCount = 0;

     int otherTmpVarCount = 0;

@@ -1554,7 +1560,7 @@ namespace Microsoft.Dafny {
       // the procedure itself

       Bpl.RequiresSeq req = new Bpl.RequiresSeq();

       // free requires mh == ModuleContextHeight && fh == FunctionContextHeight;

-      ModuleDecl mod = f.EnclosingClass.Module;

+      ModuleDefinition mod = f.EnclosingClass.Module;

       Bpl.Expr context = Bpl.Expr.And(

         Bpl.Expr.Eq(Bpl.Expr.Literal(mod.Height), etran.ModuleContextHeight()),

         Bpl.Expr.Eq(Bpl.Expr.Literal(mod.CallGraph.GetSCCRepresentativeId(f)), etran.FunctionContextHeight()));

@@ -2372,7 +2378,7 @@ namespace Microsoft.Dafny {
 

           if (options.Decr != null && e.CoCall != FunctionCallExpr.CoCallResolution.Yes) {

             // check that the decreases measure goes down

-            ModuleDecl module = cce.NonNull(e.Function.EnclosingClass).Module;

+            ModuleDefinition module = cce.NonNull(e.Function.EnclosingClass).Module;

             if (module == cce.NonNull(options.Decr.EnclosingClass).Module) {

               if (module.CallGraph.GetSCCRepresentative(e.Function) == module.CallGraph.GetSCCRepresentative(options.Decr)) {

                 bool contextDecrInferred, calleeDecrInferred;

@@ -2819,7 +2825,7 @@ namespace Microsoft.Dafny {
       } else if (type is IntType) {

         return new Bpl.IdentifierExpr(tok, "class._System.int", predef.ClassNameType);

       } else if (type is ObjectType) {

-        return new Bpl.IdentifierExpr(tok, "class._System.object", predef.ClassNameType);

+        return new Bpl.IdentifierExpr(tok, GetClass(program.BuiltIns.ObjectDecl));

       } else if (type is CollectionType) {

         CollectionType ct = (CollectionType)type;

         Bpl.Expr a = GetTypeExpr(tok, ct.Arg);

@@ -4394,7 +4400,7 @@ namespace Microsoft.Dafny {
       CheckFrameSubset(tok, method.Mod.Expressions, receiver, substMap, etran, builder, "call may violate context's modifies clause", null);

 

       // Check termination

-      ModuleDecl module = method.EnclosingClass.Module;

+      ModuleDefinition module = method.EnclosingClass.Module;

       if (module == currentModule) {

         if (module.CallGraph.GetSCCRepresentative(method) == module.CallGraph.GetSCCRepresentative(currentMethod)) {

           bool contextDecrInferred, calleeDecrInferred;

@@ -5298,7 +5304,7 @@ namespace Microsoft.Dafny {
           typeArgs.Add(tRhs.EType);

           rightType = etran.GoodRef_Ref(tok, nw, new Bpl.IdentifierExpr(tok, "class._System." + BuiltIns.ArrayClassName(tRhs.ArrayDimensions.Count), predef.ClassNameType), typeArgs, true);

         } else if (tRhs.EType is ObjectType) {

-          rightType = etran.GoodRef_Ref(tok, nw, new Bpl.IdentifierExpr(tok, "class._System.object", predef.ClassNameType), new List<Type>(), true);

+          rightType = etran.GoodRef_Ref(tok, nw, new Bpl.IdentifierExpr(Token.NoToken,GetClass(program.BuiltIns.ObjectDecl)), new List<Type>(), true);

         } else {

           rightType = etran.GoodRef_Class(tok, nw, (UserDefinedType)tRhs.EType, true);

         }

@@ -5714,7 +5720,7 @@ namespace Microsoft.Dafny {
           }

           string nm = FunctionName(e.Function, 1 + offsetToUse);

           if (this.applyLimited_CurrentFunction != null && e.Function.IsRecursive) {

-            ModuleDecl module = cce.NonNull(e.Function.EnclosingClass).Module;

+            ModuleDefinition module = cce.NonNull(e.Function.EnclosingClass).Module;

             if (module == cce.NonNull(applyLimited_CurrentFunction.EnclosingClass).Module) {

               if (module.CallGraph.GetSCCRepresentative(e.Function) == module.CallGraph.GetSCCRepresentative(applyLimited_CurrentFunction)) {

                 nm = FunctionName(e.Function, 0 + offsetToUse);

diff --git a/Source/Dafny/Util.cs b/Source/Dafny/Util.cs
new file mode 100644
index 00000000..e057727a
--- /dev/null
+++ b/Source/Dafny/Util.cs
@@ -0,0 +1,20 @@
+using System;

+using System.Collections.Generic;

+using System.Linq;

+using System.Text;

+

+namespace Microsoft.Dafny {

+  class Util

+  {

+     public delegate string ToString<T>(T t);

+     public static string Comma<T>(string comma, List<T> l, ToString<T> f) {

+       string res = "";

+       string c = "";

+       foreach(var t in l) {

+         res += c + f(t);

+         c = comma;

+       }

+       return res;

+     }

+  }

+}

diff --git a/Source/GPUVerify/RaceInstrumenter.cs b/Source/GPUVerify/RaceInstrumenter.cs
deleted file mode 100644
index 620f7d1a..00000000
--- a/Source/GPUVerify/RaceInstrumenter.cs
+++ /dev/null
@@ -1,1042 +0,0 @@
-using System;

-using System.Collections.Generic;

-using System.Linq;

-using System.Text;

-using System.Diagnostics;

-using System.Diagnostics.Contracts;

-using Microsoft.Boogie;

-using Microsoft.Basetypes;

-

-namespace GPUVerify

-{

-    class RaceInstrumenter : IRaceInstrumenter

-    {

-        protected GPUVerifier verifier;

-

-        public INonLocalState NonLocalStateToCheck;

-

-        public int onlyLog1;

-        public int onlyLog2;

-        public bool failedToFindSecondAccess;

-        public bool addedLogWrite;

-        private int logAddCount;

-

-        private Dictionary<string, Procedure> logAccessProcedures = new Dictionary<string, Procedure>();

-

-        public RaceInstrumenter()

-        {

-            onlyLog1 = -1;

-            onlyLog2 = -1;

-            failedToFindSecondAccess = false;

-            addedLogWrite = false;

-            logAddCount = 0;

-        }

-

-        public void setVerifier(GPUVerifier verifier)

-        {

-            this.verifier = verifier;

-            NonLocalStateToCheck = new NonLocalStateLists();

-            foreach(Variable v in verifier.NonLocalState.getGlobalVariables())

-            {

-                NonLocalStateToCheck.getGlobalVariables().Add(v);

-            }

-            foreach(Variable v in verifier.NonLocalState.getGroupSharedVariables())

-            {

-                NonLocalStateToCheck.getGroupSharedVariables().Add(v);

-            }

-        }

-

-        private void AddNoReadOrWriteCandidateInvariants(IRegion region, Variable v)

-        {

-            // Reasoning: if READ_HAS_OCCURRED_v is not in the modifies set for the

-            // loop then there is no point adding an invariant

-            //

-            // If READ_HAS_OCCURRED_v is in the modifies set, but the loop does not

-            // contain a barrier, then it is almost certain that a read CAN be

-            // pending at the loop head, so the invariant will not hold

-            //

-            // If there is a barrier in the loop body then READ_HAS_OCCURRED_v will

-            // be in the modifies set, but there may not be a live read at the loop

-            // head, so it is worth adding the loop invariant candidate.

-            //

-            // The same reasoning applies for WRITE

-

-            if (verifier.ContainsBarrierCall(region))

-            {

-                if (verifier.ContainsNamedVariable(

-                    LoopInvariantGenerator.GetModifiedVariables(region), GPUVerifier.MakeAccessHasOccurredVariableName(v.Name, "READ")))

-                {

-                    AddNoReadOrWriteCandidateInvariant(region, v, "READ");

-                }

-

-                if (verifier.ContainsNamedVariable(

-                    LoopInvariantGenerator.GetModifiedVariables(region), GPUVerifier.MakeAccessHasOccurredVariableName(v.Name, "WRITE")))

-                {

-                    AddNoReadOrWriteCandidateInvariant(region, v, "WRITE");

-                }

-            }

-        }

-

-        private void AddNoReadOrWriteCandidateRequires(Procedure Proc, Variable v)

-        {

-            AddNoReadOrWriteCandidateRequires(Proc, v, "READ", "1");

-            AddNoReadOrWriteCandidateRequires(Proc, v, "WRITE", "1");

-        }

-

-        private void AddNoReadOrWriteCandidateEnsures(Procedure Proc, Variable v)

-        {

-            AddNoReadOrWriteCandidateEnsures(Proc, v, "READ", "1");

-            AddNoReadOrWriteCandidateEnsures(Proc, v, "WRITE", "1");

-        }

-

-        private void AddNoReadOrWriteCandidateInvariant(IRegion region, Variable v, string ReadOrWrite)

-        {

-            Expr candidate = NoReadOrWriteExpr(v, ReadOrWrite, "1");

-            verifier.AddCandidateInvariant(region, candidate, "no " + ReadOrWrite.ToLower());

-        }

-

-        public void AddRaceCheckingCandidateInvariants(Implementation impl, IRegion region)

-        {

-            foreach (Variable v in NonLocalStateToCheck.getAllNonLocalVariables())

-            {

-                AddNoReadOrWriteCandidateInvariants(region, v);

-                AddReadOrWrittenOffsetIsThreadIdCandidateInvariants(impl, region, v, "READ");

-                AddReadOrWrittenOffsetIsThreadIdCandidateInvariants(impl, region, v, "WRITE");

-                AddOffsetsSatisfyPredicatesCandidateInvariant(region, v, "READ", CollectOffsetPredicates(impl, region, v, "READ"));

-                AddOffsetsSatisfyPredicatesCandidateInvariant(region, v, "WRITE", CollectOffsetPredicates(impl, region, v, "WRITE"));

-            }

-        }

-

-        private void AddAccessRelatedCandidateInvariant(IRegion region, string accessKind, Expr candidateInvariantExpr, string procName, string tag)

-        {

-            Expr candidate = new VariableDualiser(1, verifier.uniformityAnalyser, procName).VisitExpr(candidateInvariantExpr.Clone() as Expr);

-            verifier.AddCandidateInvariant(region, candidate, tag);

-        }

-

-        private bool DoesNotReferTo(Expr expr, string v)

-        {

-            FindReferencesToNamedVariableVisitor visitor = new FindReferencesToNamedVariableVisitor(v);

-            visitor.VisitExpr(expr);

-            return !visitor.found;

-        }

-

-        private List<Expr> CollectOffsetPredicates(Implementation impl, IRegion region, Variable v, string accessType)

-        {

-            var offsetVar = new VariableDualiser(1, null, null).VisitVariable(GPUVerifier.MakeOffsetXVariable(v, accessType));

-            var offsetExpr = new IdentifierExpr(Token.NoToken, offsetVar);

-            var offsetPreds = new List<Expr>();

-

-            foreach (var offset in GetOffsetsAccessed(region, v, accessType))

-            {

-                bool isConstant;

-                var def = verifier.varDefAnalyses[impl].SubstDefinitions(offset, impl.Name, out isConstant);

-                if (def == null)

-                    continue;

-

-                if (isConstant)

-                {

-                    offsetPreds.Add(Expr.Eq(offsetExpr, def));

-                }

-                else

-                {

-                    var sc = StrideConstraint.FromExpr(verifier, impl, def);

-                    var pred = sc.MaybeBuildPredicate(verifier, offsetExpr);

-                    if (pred != null)

-                        offsetPreds.Add(pred);

-                }

-            }

-

-            return offsetPreds;

-        }

-

-        private void AddReadOrWrittenOffsetIsThreadIdCandidateInvariants(Implementation impl, IRegion region, Variable v, string accessType)

-        {

-            KeyValuePair<IdentifierExpr, Expr> iLessThanC = GetILessThanC(region.Guard());

-            if (iLessThanC.Key != null)

-            {

-                foreach (Expr e in GetOffsetsAccessed(region, v, accessType))

-                {

-                    if(HasFormIPlusLocalIdTimesC(e, iLessThanC, impl))

-                    {

-                        AddAccessedOffsetInRangeCTimesLocalIdToCTimesLocalIdPlusC(region, v, iLessThanC.Value, accessType);

-                        break;

-                    }

-                }

-

-                foreach (Expr e in GetOffsetsAccessed(region, v, accessType))

-                {

-                    if (HasFormIPlusGlobalIdTimesC(e, iLessThanC, impl))

-                    {

-                        AddAccessedOffsetInRangeCTimesGlobalIdToCTimesGlobalIdPlusC(region, v, iLessThanC.Value, accessType);

-                        break;

-                    }

-                }

-            

-            }

-

-        

-        }

-

-        private bool HasFormIPlusLocalIdTimesC(Expr e, KeyValuePair<IdentifierExpr, Expr> iLessThanC, Implementation impl)

-        {

-            if (!(e is NAryExpr))

-            {

-                return false;

-            }

-

-            NAryExpr nary = e as NAryExpr;

-

-            if (!nary.Fun.FunctionName.Equals("BV32_ADD"))

-            {

-                return false;

-            }

-

-            return (SameIdentifierExpression(nary.Args[0], iLessThanC.Key) &&

-                IsLocalIdTimesConstant(nary.Args[1], iLessThanC.Value, impl)) ||

-                (SameIdentifierExpression(nary.Args[1], iLessThanC.Key) &&

-                IsLocalIdTimesConstant(nary.Args[0], iLessThanC.Value, impl));

-        }

-

-        private bool IsLocalIdTimesConstant(Expr maybeLocalIdTimesConstant, Expr constant, Implementation impl)

-        {

-            if (!(maybeLocalIdTimesConstant is NAryExpr))

-            {

-                return false;

-            }

-            NAryExpr nary = maybeLocalIdTimesConstant as NAryExpr;

-            if(!nary.Fun.FunctionName.Equals("BV32_MUL"))

-            {

-                return false;

-            }

-

-            return

-                (SameConstant(nary.Args[0], constant) && verifier.IsLocalId(nary.Args[1], 0, impl)) ||

-                (SameConstant(nary.Args[1], constant) && verifier.IsLocalId(nary.Args[0], 0, impl));

-        }

-

-

-        private bool HasFormIPlusGlobalIdTimesC(Expr e, KeyValuePair<IdentifierExpr, Expr> iLessThanC, Implementation impl)

-        {

-            if (!(e is NAryExpr))

-            {

-                return false;

-            }

-

-            NAryExpr nary = e as NAryExpr;

-

-            if (!nary.Fun.FunctionName.Equals("BV32_ADD"))

-            {

-                return false;

-            }

-

-            return (SameIdentifierExpression(nary.Args[0], iLessThanC.Key) &&

-                IsGlobalIdTimesConstant(nary.Args[1], iLessThanC.Value, impl)) ||

-                (SameIdentifierExpression(nary.Args[1], iLessThanC.Key) &&

-                IsGlobalIdTimesConstant(nary.Args[0], iLessThanC.Value, impl));

-        }

-

-        private bool IsGlobalIdTimesConstant(Expr maybeGlobalIdTimesConstant, Expr constant, Implementation impl)

-        {

-            if (!(maybeGlobalIdTimesConstant is NAryExpr))

-            {

-                return false;

-            }

-            NAryExpr nary = maybeGlobalIdTimesConstant as NAryExpr;

-            if (!nary.Fun.FunctionName.Equals("BV32_MUL"))

-            {

-                return false;

-            }

-

-            return

-                (SameConstant(nary.Args[0], constant) && verifier.IsGlobalId(nary.Args[1], 0, impl)) ||

-                (SameConstant(nary.Args[1], constant) && verifier.IsGlobalId(nary.Args[0], 0, impl));

-        }

-

-

-        private bool SameConstant(Expr expr, Expr constant)

-        {

-            if (constant is IdentifierExpr)

-            {

-                IdentifierExpr identifierExpr = constant as IdentifierExpr;

-                Debug.Assert(identifierExpr.Decl is Constant);

-                return expr is IdentifierExpr && (expr as IdentifierExpr).Decl is Constant && (expr as IdentifierExpr).Decl.Name.Equals(identifierExpr.Decl.Name);

-            }

-            else

-            {

-                Debug.Assert(constant is LiteralExpr);

-                LiteralExpr literalExpr = constant as LiteralExpr;

-                if (!(expr is LiteralExpr))

-                {

-                    return false;

-                }

-                if (!(literalExpr.Val is BvConst) || !((expr as LiteralExpr).Val is BvConst))

-                {

-                    return false;

-                }

-

-                return (literalExpr.Val as BvConst).Value.ToInt == ((expr as LiteralExpr).Val as BvConst).Value.ToInt;

-            }

-        }

-

-        private bool SameIdentifierExpression(Expr expr, IdentifierExpr identifierExpr)

-        {

-            if (!(expr is IdentifierExpr))

-            {

-                return false;

-            }

-            return (expr as IdentifierExpr).Decl.Name.Equals(identifierExpr.Name);

-        }

-

-        private KeyValuePair<IdentifierExpr, Expr> GetILessThanC(Expr expr)

-        {

-

-            if (expr is NAryExpr && (expr as NAryExpr).Fun.FunctionName.Equals("bv32_to_bool"))

-            {

-                expr = (expr as NAryExpr).Args[0];

-            }

-

-            if (!(expr is NAryExpr))

-            {

-                return new KeyValuePair<IdentifierExpr, Expr>(null, null);

-            }

-

-            NAryExpr nary = expr as NAryExpr;

-

-            if (!(nary.Fun.FunctionName.Equals("BV32_C_LT") || nary.Fun.FunctionName.Equals("BV32_LT")))

-            {

-                return new KeyValuePair<IdentifierExpr, Expr>(null, null);

-            }

-

-            if (!(nary.Args[0] is IdentifierExpr))

-            {

-                return new KeyValuePair<IdentifierExpr, Expr>(null, null);

-            }

-

-            if (!IsConstant(nary.Args[1]))

-            {

-                return new KeyValuePair<IdentifierExpr, Expr>(null, null);

-            }

-

-            return new KeyValuePair<IdentifierExpr, Expr>(nary.Args[0] as IdentifierExpr, nary.Args[1]);

-

-        }

-

-        private static bool IsConstant(Expr e)

-        {

-            return ((e is IdentifierExpr && (e as IdentifierExpr).Decl is Constant) || e is LiteralExpr);

-        }

-

-        private void AddReadOrWrittenOffsetIsThreadIdCandidateRequires(Procedure Proc, Variable v)

-        {

-            AddAccessedOffsetIsThreadLocalIdCandidateRequires(Proc, v, "WRITE", 1);

-            AddAccessedOffsetIsThreadLocalIdCandidateRequires(Proc, v, "READ", 1);

-        }

-

-        private void AddReadOrWrittenOffsetIsThreadIdCandidateEnsures(Procedure Proc, Variable v)

-        {

-            AddAccessedOffsetIsThreadLocalIdCandidateEnsures(Proc, v, "WRITE", 1);

-            AddAccessedOffsetIsThreadLocalIdCandidateEnsures(Proc, v, "READ", 1);

-        }

-

-        public void AddKernelPrecondition()

-        {

-            foreach (Variable v in NonLocalStateToCheck.getAllNonLocalVariables())

-            {

-                AddRequiresNoPendingAccess(v);

-

-                if (!verifier.ArrayModelledAdversarially(v))

-                {

-                    IdentifierExpr v1 = new IdentifierExpr(Token.NoToken, new VariableDualiser(1, null, null).VisitVariable(v.Clone() as Variable));

-                    IdentifierExpr v2 = new IdentifierExpr(Token.NoToken, new VariableDualiser(2, null, null).VisitVariable(v.Clone() as Variable));

-                    verifier.KernelProcedure.Requires.Add(new Requires(false, Expr.Eq(v1, v2)));

-                }

-            }

-        }

-

-        public bool AddRaceCheckingInstrumentation()

-        {

-

-            if (onlyLog1 != -1)

-            {

-                addedLogWrite = false;

-                failedToFindSecondAccess = true;

-            }

-            else

-            {

-                addedLogWrite = true;

-                failedToFindSecondAccess = false;

-            }

-

-            foreach (Declaration d in verifier.Program.TopLevelDeclarations)

-            {

-                if (d is Implementation)

-                {

-                    AddRaceCheckCalls(d as Implementation);

-                }

-            }

-

-            if (failedToFindSecondAccess || !addedLogWrite)

-                return false;

-

-            return true;

-

-        }

-

-        private void AddRaceCheckingDecsAndProcsForVar(Variable v)

-        {

-            AddLogRaceDeclarations(v, "READ");

-            AddLogRaceDeclarations(v, "WRITE");

-            AddLogAccessProcedure(v, "READ");

-            AddLogAccessProcedure(v, "WRITE");

-

-        }

-        

-        private StmtList AddRaceCheckCalls(StmtList stmtList)

-        {

-            Contract.Requires(stmtList != null);

-

-            StmtList result = new StmtList(new List<BigBlock>(), stmtList.EndCurly);

-

-            foreach (BigBlock bodyBlock in stmtList.BigBlocks)

-            {

-                result.BigBlocks.Add(AddRaceCheckCalls(bodyBlock));

-            }

-            return result;

-        }

-

-        private Block AddRaceCheckCalls(Block b)

-        {

-            b.Cmds = AddRaceCheckCalls(b.Cmds);

-            return b;

-        }

-

-        private void AddRaceCheckCalls(Implementation impl)

-        {

-            if (CommandLineOptions.Unstructured)

-                impl.Blocks = impl.Blocks.Select(AddRaceCheckCalls).ToList();

-            else

-                impl.StructuredStmts = AddRaceCheckCalls(impl.StructuredStmts);

-        }

-

-        private bool shouldAddLogCallAndIncr()

-        {

-            Contract.Assert(onlyLog1 >= -1);

-            int oldLogAddCount = logAddCount;

-            ++logAddCount;

-

-            if (onlyLog1 == -1)

-            {

-                return true;

-            }

-

-            if(onlyLog1 + onlyLog2 == oldLogAddCount)

-            {

-                failedToFindSecondAccess = false;

-                return true;

-            }

-

-            if (onlyLog1 == oldLogAddCount)

-            {

-                return true;

-            }

-

-            return false;

-        }

-

-        private CmdSeq AddRaceCheckCalls(CmdSeq cs)

-        {

-            var result = new CmdSeq();

-            foreach (Cmd c in cs)

-            {

-                result.Add(c);

-                if (c is AssignCmd)

-                {

-                    AssignCmd assign = c as AssignCmd;

-

-                    ReadCollector rc = new ReadCollector(NonLocalStateToCheck);

-                    foreach (var rhs in assign.Rhss)

-                        rc.Visit(rhs);

-                    if (rc.accesses.Count > 0)

-                    {

-                        foreach (AccessRecord ar in rc.accesses)

-                        {

-                            if (shouldAddLogCallAndIncr())

-                            {

-

-                                ExprSeq inParams = new ExprSeq();

-                                if (ar.IndexZ != null)

-                                {

-                                    inParams.Add(ar.IndexZ);

-                                }

-                                if (ar.IndexY != null)

-                                {

-                                    inParams.Add(ar.IndexY);

-                                }

-                                if (ar.IndexX != null)

-                                {

-                                    inParams.Add(ar.IndexX);

-                                }

-

-                                Procedure logProcedure = GetLogAccessProcedure(c.tok, "_LOG_READ_" + ar.v.Name);

-

-                                CallCmd logAccessCallCmd = new CallCmd(c.tok, logProcedure.Name, inParams, new IdentifierExprSeq());

-

-                                logAccessCallCmd.Proc = logProcedure;

-

-                                result.Add(logAccessCallCmd);

-

-                            }

-                        }

-                    }

-

-                    foreach (var lhs in assign.Lhss)

-                    {

-                        WriteCollector wc = new WriteCollector(NonLocalStateToCheck);

-                        wc.Visit(lhs);

-                        if (wc.GetAccess() != null)

-                        {

-                            AccessRecord ar = wc.GetAccess();

-

-                            if (shouldAddLogCallAndIncr())

-                            {

-

-                                ExprSeq inParams = new ExprSeq();

-                                if (ar.IndexZ != null)

-                                {

-                                    inParams.Add(ar.IndexZ);

-                                }

-                                if (ar.IndexY != null)

-                                {

-                                    inParams.Add(ar.IndexY);

-                                }

-                                if (ar.IndexX != null)

-                                {

-                                    inParams.Add(ar.IndexX);

-                                }

-

-                                Procedure logProcedure = GetLogAccessProcedure(c.tok, "_LOG_WRITE_" + ar.v.Name);

-

-                                CallCmd logAccessCallCmd = new CallCmd(c.tok, logProcedure.Name, inParams, new IdentifierExprSeq());

-

-                                logAccessCallCmd.Proc = logProcedure;

-

-                                result.Add(logAccessCallCmd);

-

-                                addedLogWrite = true;

-

-                            }

-                        }

-                    }

-                }

-            }

-            return result;

-        }

-

-        private BigBlock AddRaceCheckCalls(BigBlock bb)

-        {

-            BigBlock result = new BigBlock(bb.tok, bb.LabelName, AddRaceCheckCalls(bb.simpleCmds), null, bb.tc);

-

-            if (bb.ec is WhileCmd)

-            {

-                WhileCmd WhileCommand = bb.ec as WhileCmd;

-                result.ec = new WhileCmd(WhileCommand.tok, WhileCommand.Guard, 

-                        WhileCommand.Invariants, AddRaceCheckCalls(WhileCommand.Body));

-            }

-            else if (bb.ec is IfCmd)

-            {

-                IfCmd IfCommand = bb.ec as IfCmd;

-                Debug.Assert(IfCommand.elseIf == null); // We don't handle else if yet

-                result.ec = new IfCmd(IfCommand.tok, IfCommand.Guard, AddRaceCheckCalls(IfCommand.thn), IfCommand.elseIf, IfCommand.elseBlock != null ? AddRaceCheckCalls(IfCommand.elseBlock) : null);

-            }

-            else if (bb.ec is BreakCmd)

-            {

-                result.ec = bb.ec;

-            }

-            else

-            {

-                Debug.Assert(bb.ec == null);

-            }

-

-            return result;

-        }

-

-        private Procedure GetLogAccessProcedure(IToken tok, string name)

-        {

-            if (logAccessProcedures.ContainsKey(name))

-            {

-                return logAccessProcedures[name];

-            }

-            Procedure newProcedure = new Procedure(tok, name, new TypeVariableSeq(), new VariableSeq(), new VariableSeq(), new RequiresSeq(), new IdentifierExprSeq(), new EnsuresSeq());

-            logAccessProcedures[name] = newProcedure;

-            return newProcedure;

-        }

-

-

-        public BigBlock MakeResetReadWriteSetStatements(Variable v, int Thread)

-        {

-            BigBlock result = new BigBlock(Token.NoToken, null, new CmdSeq(), null, null);

-            if (Thread == 2)

-            {

-                return result;

-            }

-

-            Expr ResetReadAssumeGuard = Expr.Not(new IdentifierExpr(Token.NoToken,

-                new VariableDualiser(1, null, null).VisitVariable(GPUVerifier.MakeAccessHasOccurredVariable(v.Name, "READ"))));

-            Expr ResetWriteAssumeGuard = Expr.Not(new IdentifierExpr(Token.NoToken,

-                new VariableDualiser(1, null, null).VisitVariable(GPUVerifier.MakeAccessHasOccurredVariable(v.Name, "WRITE"))));

-

-            if (CommandLineOptions.InterGroupRaceChecking && verifier.NonLocalState.getGlobalVariables().Contains(v))

-            {

-                ResetReadAssumeGuard = Expr.Imp(verifier.ThreadsInSameGroup(), ResetReadAssumeGuard);

-                ResetWriteAssumeGuard = Expr.Imp(verifier.ThreadsInSameGroup(), ResetWriteAssumeGuard);

-            }

-

-            result.simpleCmds.Add(new AssumeCmd(Token.NoToken, ResetReadAssumeGuard));

-            result.simpleCmds.Add(new AssumeCmd(Token.NoToken, ResetWriteAssumeGuard));

-            return result;

-        }

-

-        protected Procedure MakeLogAccessProcedureHeader(Variable v, string ReadOrWrite)

-        {

-            VariableSeq inParams = new VariableSeq();

-

-            Variable PredicateParameter = new LocalVariable(v.tok, new TypedIdent(v.tok, "_P", Microsoft.Boogie.Type.Bool));

-

-            Debug.Assert(v.TypedIdent.Type is MapType);

-            MapType mt = v.TypedIdent.Type as MapType;

-            Debug.Assert(mt.Arguments.Length == 1);

-            Variable OffsetParameter = new LocalVariable(v.tok, new TypedIdent(v.tok, "_offset", mt.Arguments[0]));

-            Debug.Assert(!(mt.Result is MapType));

-

-            inParams.Add(new VariableDualiser(1, null, null).VisitVariable(PredicateParameter.Clone() as Variable));

-            inParams.Add(new VariableDualiser(1, null, null).VisitVariable(OffsetParameter.Clone() as Variable));

-

-            inParams.Add(new VariableDualiser(2, null, null).VisitVariable(PredicateParameter.Clone() as Variable));

-            inParams.Add(new VariableDualiser(2, null, null).VisitVariable(OffsetParameter.Clone() as Variable));

-

-            string LogProcedureName = "_LOG_" + ReadOrWrite + "_" + v.Name;

-

-            Procedure result = GetLogAccessProcedure(v.tok, LogProcedureName);

-

-            result.InParams = inParams;

-

-            result.AddAttribute("inline", new object[] { new LiteralExpr(v.tok, BigNum.FromInt(1)) });

-

-            return result;

-        }

-

-        public void AddRaceCheckingCandidateRequires(Procedure Proc)

-        {

-            foreach (Variable v in NonLocalStateToCheck.getAllNonLocalVariables())

-            {

-                AddNoReadOrWriteCandidateRequires(Proc, v);

-                AddReadOrWrittenOffsetIsThreadIdCandidateRequires(Proc, v);

-            }

-        }

-

-        public void AddRaceCheckingCandidateEnsures(Procedure Proc)

-        {

-            foreach (Variable v in NonLocalStateToCheck.getAllNonLocalVariables())

-            {

-                AddNoReadOrWriteCandidateEnsures(Proc, v);

-                AddReadOrWrittenOffsetIsThreadIdCandidateEnsures(Proc, v);

-            }

-        }

-

-        private void AddNoReadOrWriteCandidateRequires(Procedure Proc, Variable v, string ReadOrWrite, string OneOrTwo)

-        {

-            verifier.AddCandidateRequires(Proc, NoReadOrWriteExpr(v, ReadOrWrite, OneOrTwo));

-        }

-

-        private void AddNoReadOrWriteCandidateEnsures(Procedure Proc, Variable v, string ReadOrWrite, string OneOrTwo)

-        {

-            verifier.AddCandidateEnsures(Proc, NoReadOrWriteExpr(v, ReadOrWrite, OneOrTwo));

-        }

-

-        private HashSet<Expr> GetOffsetsAccessed(IRegion region, Variable v, string AccessType)

-        {

-            HashSet<Expr> result = new HashSet<Expr>();

-

-            foreach (Cmd c in region.Cmds())

-            {

-                if (c is CallCmd)

-                {

-                    CallCmd call = c as CallCmd;

-

-                    if (call.callee == "_LOG_" + AccessType + "_" + v.Name)

-                    {

-                        // Ins[0] is thread 1's predicate,

-                        // Ins[1] is the offset to be read

-                        // If Ins[1] has the form BV32_ADD(offset#construct...(P), offset),

-                        // we are looking for the second parameter to this BV32_ADD

-                        Expr offset = call.Ins[1];

-                        if (offset is NAryExpr)

-                        {

-                            var nExpr = (NAryExpr)offset;

-                            if (nExpr.Fun.FunctionName == "BV32_ADD" &&

-                                nExpr.Args[0] is NAryExpr)

-                            {

-                                var n0Expr = (NAryExpr)nExpr.Args[0];

-                                if (n0Expr.Fun.FunctionName.StartsWith("offset#"))

-                                    offset = nExpr.Args[1];

-                            }

-                        }

-                        result.Add(offset);

-                    }

-

-                }

-

-            }

-

-            return result;

-        }

-

-        public void AddRaceCheckingDeclarations()

-        {

-            foreach (Variable v in NonLocalStateToCheck.getAllNonLocalVariables())

-            {

-                AddRaceCheckingDecsAndProcsForVar(v);

-            }

-        }

-

-        protected void AddLogAccessProcedure(Variable v, string Access)

-        {

-            Procedure LogAccessProcedure = MakeLogAccessProcedureHeader(v, Access);

-

-            Variable AccessHasOccurredVariable = GPUVerifier.MakeAccessHasOccurredVariable(v.Name, Access);

-            Variable AccessOffsetXVariable = GPUVerifier.MakeOffsetXVariable(v, Access);

-

-            Variable PredicateParameter = new LocalVariable(v.tok, new TypedIdent(v.tok, "_P", Microsoft.Boogie.Type.Bool));

-

-            Debug.Assert(v.TypedIdent.Type is MapType);

-            MapType mt = v.TypedIdent.Type as MapType;

-            Debug.Assert(mt.Arguments.Length == 1);

-            Variable OffsetParameter = new LocalVariable(v.tok, new TypedIdent(v.tok, "_offset", mt.Arguments[0]));

-            Debug.Assert(!(mt.Result is MapType));

-

-            VariableSeq locals = new VariableSeq();

-            Variable TrackVariable = new LocalVariable(v.tok, new TypedIdent(v.tok, "track", Microsoft.Boogie.Type.Bool));

-            locals.Add(TrackVariable);

-

-            List<BigBlock> bigblocks = new List<BigBlock>();

-

-            CmdSeq simpleCmds = new CmdSeq();

-

-            simpleCmds.Add(new HavocCmd(v.tok, new IdentifierExprSeq(new IdentifierExpr[] { new IdentifierExpr(v.tok, TrackVariable) })));

-

-            simpleCmds.Add(MakeConditionalAssignment(VariableForThread(1, AccessHasOccurredVariable), 

-                Expr.And(new IdentifierExpr(v.tok, VariableForThread(1, PredicateParameter)), new IdentifierExpr(v.tok, TrackVariable)), Expr.True));

-            simpleCmds.Add(MakeConditionalAssignment(VariableForThread(1, AccessOffsetXVariable), 

-                Expr.And(new IdentifierExpr(v.tok, VariableForThread(1, PredicateParameter)), new IdentifierExpr(v.tok, TrackVariable)), 

-                new IdentifierExpr(v.tok, VariableForThread(1, OffsetParameter))));

-

-            if (Access.Equals("READ"))

-            {

-                // Check read by thread 2 does not conflict with write by thread 1

-                Variable WriteHasOccurredVariable = GPUVerifier.MakeAccessHasOccurredVariable(v.Name, "WRITE");

-                Variable WriteOffsetXVariable = GPUVerifier.MakeOffsetXVariable(v, "WRITE");

-                Expr WriteReadGuard = new IdentifierExpr(Token.NoToken, VariableForThread(2, PredicateParameter));

-                WriteReadGuard = Expr.And(WriteReadGuard, new IdentifierExpr(Token.NoToken, VariableForThread(1, WriteHasOccurredVariable)));

-                WriteReadGuard = Expr.And(WriteReadGuard, Expr.Eq(new IdentifierExpr(Token.NoToken, VariableForThread(1, WriteOffsetXVariable)), 

-                                                new IdentifierExpr(Token.NoToken, VariableForThread(2, OffsetParameter))));

-                if (!verifier.ArrayModelledAdversarially(v))

-                {

-                    WriteReadGuard = Expr.And(WriteReadGuard, Expr.Neq(

-                        MakeAccessedIndex(v, new IdentifierExpr(Token.NoToken, VariableForThread(1, WriteOffsetXVariable)), 1, "WRITE"),

-                        MakeAccessedIndex(v, new IdentifierExpr(Token.NoToken, VariableForThread(2, OffsetParameter)), 2, "READ")

-                        ));

-                }

-

-                if (verifier.NonLocalState.getGroupSharedVariables().Contains(v) && CommandLineOptions.InterGroupRaceChecking)

-                {

-                    WriteReadGuard = Expr.And(WriteReadGuard, verifier.ThreadsInSameGroup());

-                }

-

-                WriteReadGuard = Expr.Not(WriteReadGuard);

-                simpleCmds.Add(new AssertCmd(Token.NoToken, WriteReadGuard));

-            }

-            else

-            {

-                Debug.Assert(Access.Equals("WRITE"));

-

-                // Check write by thread 2 does not conflict with write by thread 1

-                Variable WriteHasOccurredVariable = GPUVerifier.MakeAccessHasOccurredVariable(v.Name, "WRITE");

-                Variable WriteOffsetXVariable = GPUVerifier.MakeOffsetXVariable(v, "WRITE");

-

-                Expr WriteWriteGuard = new IdentifierExpr(Token.NoToken, VariableForThread(2, PredicateParameter));

-                WriteWriteGuard = Expr.And(WriteWriteGuard, new IdentifierExpr(Token.NoToken, VariableForThread(1, WriteHasOccurredVariable)));

-                WriteWriteGuard = Expr.And(WriteWriteGuard, Expr.Eq(new IdentifierExpr(Token.NoToken, VariableForThread(1, WriteOffsetXVariable)),

-                                                new IdentifierExpr(Token.NoToken, VariableForThread(2, OffsetParameter))));

-                if (!verifier.ArrayModelledAdversarially(v))

-                {

-                    WriteWriteGuard = Expr.And(WriteWriteGuard, Expr.Neq(

-                        MakeAccessedIndex(v, new IdentifierExpr(Token.NoToken, VariableForThread(1, WriteOffsetXVariable)), 1, "WRITE"),

-                        MakeAccessedIndex(v, new IdentifierExpr(Token.NoToken, VariableForThread(2, OffsetParameter)), 2, "WRITE")

-                        ));

-                }

-

-                if (verifier.NonLocalState.getGroupSharedVariables().Contains(v) && CommandLineOptions.InterGroupRaceChecking)

-                {

-                    WriteWriteGuard = Expr.And(WriteWriteGuard, verifier.ThreadsInSameGroup());

-                }

-

-                WriteWriteGuard = Expr.Not(WriteWriteGuard);

-                simpleCmds.Add(new AssertCmd(Token.NoToken, WriteWriteGuard));

-

-                // Check write by thread 2 does not conflict with read by thread 1

-                Variable ReadHasOccurredVariable = GPUVerifier.MakeAccessHasOccurredVariable(v.Name, "READ");

-                Variable ReadOffsetXVariable = GPUVerifier.MakeOffsetXVariable(v, "READ");

-

-                Expr ReadWriteGuard = new IdentifierExpr(Token.NoToken, VariableForThread(2, PredicateParameter));

-                ReadWriteGuard = Expr.And(ReadWriteGuard, new IdentifierExpr(Token.NoToken, VariableForThread(1, ReadHasOccurredVariable)));

-                ReadWriteGuard = Expr.And(ReadWriteGuard, Expr.Eq(new IdentifierExpr(Token.NoToken, VariableForThread(1, ReadOffsetXVariable)),

-                                                new IdentifierExpr(Token.NoToken, VariableForThread(2, OffsetParameter))));

-                if (!verifier.ArrayModelledAdversarially(v))

-                {

-                    ReadWriteGuard = Expr.And(ReadWriteGuard, Expr.Neq(

-                        MakeAccessedIndex(v, new IdentifierExpr(Token.NoToken, VariableForThread(1, ReadOffsetXVariable)), 1, "WRITE"),

-                        MakeAccessedIndex(v, new IdentifierExpr(Token.NoToken, VariableForThread(2, OffsetParameter)), 2, "READ")

-                        ));

-                }

-

-                if (verifier.NonLocalState.getGroupSharedVariables().Contains(v) && CommandLineOptions.InterGroupRaceChecking)

-                {

-                    ReadWriteGuard = Expr.And(ReadWriteGuard, verifier.ThreadsInSameGroup());

-                }

-

-                ReadWriteGuard = Expr.Not(ReadWriteGuard);

-                simpleCmds.Add(new AssertCmd(Token.NoToken, ReadWriteGuard));

-

-            }

-

-            bigblocks.Add(new BigBlock(v.tok, "_LOG_" + Access + "", simpleCmds, null, null));

-

-            LogAccessProcedure.Modifies.Add(new IdentifierExpr(Token.NoToken, VariableForThread(1, AccessHasOccurredVariable)));

-            LogAccessProcedure.Modifies.Add(new IdentifierExpr(Token.NoToken, VariableForThread(1, AccessOffsetXVariable)));

-

-            Implementation LogAccessImplementation = new Implementation(v.tok, "_LOG_" + Access + "_" + v.Name, new TypeVariableSeq(), LogAccessProcedure.InParams, new VariableSeq(), locals, new StmtList(bigblocks, v.tok));

-            LogAccessImplementation.AddAttribute("inline", new object[] { new LiteralExpr(v.tok, BigNum.FromInt(1)) });

-

-            LogAccessImplementation.Proc = LogAccessProcedure;

-

-            verifier.Program.TopLevelDeclarations.Add(LogAccessProcedure);

-            verifier.Program.TopLevelDeclarations.Add(LogAccessImplementation);

-        }

-

-        private Variable VariableForThread(int thread, Variable v)

-        {

-            return new VariableDualiser(thread, null, null).VisitVariable(v.Clone() as Variable);

-        }

-

-        protected void AddLogRaceDeclarations(Variable v, String ReadOrWrite)

-        {

-            Variable AccessHasOccurred = GPUVerifier.MakeAccessHasOccurredVariable(v.Name, ReadOrWrite);

-

-            // Assumes full symmetry reduction

-

-            verifier.Program.TopLevelDeclarations.Add(new VariableDualiser(1, null, null).VisitVariable(AccessHasOccurred.Clone() as Variable));

-

-            Debug.Assert(v.TypedIdent.Type is MapType);

-            MapType mt = v.TypedIdent.Type as MapType;

-            Debug.Assert(mt.Arguments.Length == 1);

-

-            Variable AccessOffsetX = GPUVerifier.MakeOffsetXVariable(v, ReadOrWrite);

-            verifier.Program.TopLevelDeclarations.Add(new VariableDualiser(1, null, null).VisitVariable(AccessOffsetX.Clone() as Variable));

-

-        }

-        

-

-        private static AssignCmd MakeConditionalAssignment(Variable lhs, Expr condition, Expr rhs)

-        {

-            List<AssignLhs> lhss = new List<AssignLhs>();

-            List<Expr> rhss = new List<Expr>();

-            lhss.Add(new SimpleAssignLhs(lhs.tok, new IdentifierExpr(lhs.tok, lhs)));

-            rhss.Add(new NAryExpr(rhs.tok, new IfThenElse(rhs.tok), new ExprSeq(new Expr[] { condition, rhs, new IdentifierExpr(lhs.tok, lhs) })));

-            return new AssignCmd(lhs.tok, lhss, rhss);

-        }

-

-        private Expr MakeAccessedIndex(Variable v, Expr offsetExpr, int Thread, string AccessType)

-        {

-            Expr result = new IdentifierExpr(v.tok, new VariableDualiser(Thread, null, null).VisitVariable(v.Clone() as Variable));

-            Debug.Assert(v.TypedIdent.Type is MapType);

-            MapType mt = v.TypedIdent.Type as MapType;

-            Debug.Assert(mt.Arguments.Length == 1);

-

-            result = Expr.Select(result,

-                new Expr[] { offsetExpr });

-            Debug.Assert(!(mt.Result is MapType));

-            return result;

-        }

-

-        protected void AddRequiresNoPendingAccess(Variable v)

-        {

-            IdentifierExpr ReadAccessOccurred1 = new IdentifierExpr(v.tok, new VariableDualiser(1, null, null).VisitVariable(GPUVerifier.MakeAccessHasOccurredVariable(v.Name, "READ")));

-            IdentifierExpr WriteAccessOccurred1 = new IdentifierExpr(v.tok, new VariableDualiser(1, null, null).VisitVariable(GPUVerifier.MakeAccessHasOccurredVariable(v.Name, "WRITE")));

-

-            verifier.KernelProcedure.Requires.Add(new Requires(false, Expr.And(Expr.Not(ReadAccessOccurred1), Expr.Not(WriteAccessOccurred1))));

-        }

-

-        protected Expr NoReadOrWriteExpr(Variable v, string ReadOrWrite, string OneOrTwo)

-        {

-            Variable ReadOrWriteHasOccurred = GPUVerifier.MakeAccessHasOccurredVariable(v.Name, ReadOrWrite);

-            ReadOrWriteHasOccurred.Name = ReadOrWriteHasOccurred.Name + "$" + OneOrTwo;

-            ReadOrWriteHasOccurred.TypedIdent.Name = ReadOrWriteHasOccurred.TypedIdent.Name + "$" + OneOrTwo;

-            Expr expr = Expr.Not(new IdentifierExpr(v.tok, ReadOrWriteHasOccurred));

-            return expr;

-        }

-

-

-        protected void AddOffsetsSatisfyPredicatesCandidateInvariant(IRegion region, Variable v, string ReadOrWrite, List<Expr> preds)

-        {

-            if (preds.Count != 0)

-            {

-                Expr expr = AccessedOffsetsSatisfyPredicatesExpr(v, preds, ReadOrWrite, 1);

-                verifier.AddCandidateInvariant(region, expr, "accessed offsets satisfy predicates");

-            }

-        }

-

-        private Expr AccessedOffsetsSatisfyPredicatesExpr(Variable v, IEnumerable<Expr> offsets, string ReadOrWrite, int Thread) {

-            return Expr.Imp(

-                    new IdentifierExpr(Token.NoToken, new VariableDualiser(Thread, null, null).VisitVariable(GPUVerifier.MakeAccessHasOccurredVariable(v.Name, ReadOrWrite))),

-                    offsets.Aggregate(Expr.Or));

-        }

-

-        private Expr AccessedOffsetIsThreadLocalIdExpr(Variable v, string ReadOrWrite, int Thread)

-        {

-            Expr expr = null;

-            if (GPUVerifier.HasXDimension(v) && GPUVerifier.IndexTypeOfXDimension(v).Equals(verifier.GetTypeOfIdX()))

-            {

-                expr = Expr.Imp(

-                        new IdentifierExpr(v.tok, new VariableDualiser(Thread, null, null).VisitVariable(GPUVerifier.MakeAccessHasOccurredVariable(v.Name, ReadOrWrite))),

-                        Expr.Eq(new IdentifierExpr(v.tok, new VariableDualiser(Thread, null, null).VisitVariable(GPUVerifier.MakeOffsetXVariable(v, ReadOrWrite))), new IdentifierExpr(v.tok, verifier.MakeThreadId(v.tok, "X", Thread))));

-            }

-            return expr;

-        }

-

-        private Expr AccessedOffsetIsThreadGlobalIdExpr(Variable v, string ReadOrWrite, int Thread)

-        {

-            Expr expr = null;

-            if (GPUVerifier.HasXDimension(v) && GPUVerifier.IndexTypeOfXDimension(v).Equals(verifier.GetTypeOfIdX()))

-            {

-                expr = Expr.Imp(

-                        new IdentifierExpr(v.tok, new VariableDualiser(Thread, null, null).VisitVariable(GPUVerifier.MakeAccessHasOccurredVariable(v.Name, ReadOrWrite))),

-                        Expr.Eq(

-                            new IdentifierExpr(v.tok, new VariableDualiser(Thread, null, null).VisitVariable(GPUVerifier.MakeOffsetXVariable(v, ReadOrWrite))),

-                            GlobalIdExpr("X", Thread)

-                            )

-                            );

-            }

-            return expr;

-        }

-

-        private Expr GlobalIdExpr(string dimension, int Thread)

-        {

-            return new VariableDualiser(Thread, null, null).VisitExpr(verifier.GlobalIdExpr(dimension).Clone() as Expr);

-        }

-

-        protected void AddAccessedOffsetInRangeCTimesLocalIdToCTimesLocalIdPlusC(IRegion region, Variable v, Expr constant, string ReadOrWrite)

-        {

-            Expr expr = MakeCTimesLocalIdRangeExpression(v, constant, ReadOrWrite, 1);

-            verifier.AddCandidateInvariant(region,

-                expr, "accessed offset in range [ C*local_id, (C+1)*local_id )");

-        }

-

-        private Expr MakeCTimesLocalIdRangeExpression(Variable v, Expr constant, string ReadOrWrite, int Thread)

-        {

-            Expr CTimesLocalId = verifier.MakeBVMul(constant.Clone() as Expr, 

-                new IdentifierExpr(Token.NoToken, verifier.MakeThreadId(Token.NoToken, "X", Thread)));

-

-            Expr CTimesLocalIdPlusC = verifier.MakeBVAdd(verifier.MakeBVMul(constant.Clone() as Expr,

-                new IdentifierExpr(Token.NoToken, verifier.MakeThreadId(Token.NoToken, "X", Thread))), constant.Clone() as Expr);

-

-            Expr CTimesLocalIdLeqAccessedOffset = GPUVerifier.MakeBitVectorBinaryBoolean("BV32_LEQ", CTimesLocalId, OffsetXExpr(v, ReadOrWrite, Thread));

-

-            Expr AccessedOffsetLtCTimesLocalIdPlusC = verifier.MakeBVSlt(OffsetXExpr(v, ReadOrWrite, Thread), CTimesLocalIdPlusC);

-

-            return Expr.Imp(

-                    AccessHasOccurred(v, ReadOrWrite, Thread),

-                    Expr.And(CTimesLocalIdLeqAccessedOffset, AccessedOffsetLtCTimesLocalIdPlusC));

-        }

-

-        private static IdentifierExpr AccessHasOccurred(Variable v, string ReadOrWrite, int Thread)

-        {

-            return new IdentifierExpr(v.tok, new VariableDualiser(Thread, null, null).VisitVariable(GPUVerifier.MakeAccessHasOccurredVariable(v.Name, ReadOrWrite)));

-        }

-

-        private static IdentifierExpr OffsetXExpr(Variable v, string ReadOrWrite, int Thread)

-        {

-            return new IdentifierExpr(v.tok, new VariableDualiser(Thread, null, null).VisitVariable(GPUVerifier.MakeOffsetXVariable(v, ReadOrWrite)));

-        }

-

-        protected void AddAccessedOffsetInRangeCTimesGlobalIdToCTimesGlobalIdPlusC(IRegion region, Variable v, Expr constant, string ReadOrWrite)

-        {

-            Expr expr = MakeCTimesGloalIdRangeExpr(v, constant, ReadOrWrite, 1);

-            verifier.AddCandidateInvariant(region,

-                expr, "accessed offset in range [ C*global_id, (C+1)*global_id )");

-        }

-

-        private Expr MakeCTimesGloalIdRangeExpr(Variable v, Expr constant, string ReadOrWrite, int Thread)

-        {

-            Expr CTimesGlobalId = verifier.MakeBVMul(constant.Clone() as Expr,

-                GlobalIdExpr("X", Thread));

-

-            Expr CTimesGlobalIdPlusC = verifier.MakeBVAdd(verifier.MakeBVMul(constant.Clone() as Expr,

-                GlobalIdExpr("X", Thread)), constant.Clone() as Expr);

-

-            Expr CTimesGlobalIdLeqAccessedOffset = GPUVerifier.MakeBitVectorBinaryBoolean("BV32_LEQ", CTimesGlobalId, OffsetXExpr(v, ReadOrWrite, Thread));

-

-            Expr AccessedOffsetLtCTimesGlobalIdPlusC = verifier.MakeBVSlt(OffsetXExpr(v, ReadOrWrite, Thread), CTimesGlobalIdPlusC);

-

-            Expr implication = Expr.Imp(

-                    AccessHasOccurred(v, ReadOrWrite, Thread),

-                    Expr.And(CTimesGlobalIdLeqAccessedOffset, AccessedOffsetLtCTimesGlobalIdPlusC));

-            return implication;

-        }

-

-        protected void AddAccessedOffsetIsThreadLocalIdCandidateRequires(Procedure Proc, Variable v, string ReadOrWrite, int Thread)

-        {

-            Expr expr = AccessedOffsetIsThreadLocalIdExpr(v, ReadOrWrite, Thread);

-            if (expr != null)

-            {

-                verifier.AddCandidateRequires(Proc, expr);

-            }

-        }

-

-        protected void AddAccessedOffsetIsThreadLocalIdCandidateEnsures(Procedure Proc, Variable v, string ReadOrWrite, int Thread)

-        {

-            Expr expr = AccessedOffsetIsThreadLocalIdExpr(v, ReadOrWrite, Thread);

-            if (expr != null)

-            {

-                verifier.AddCandidateEnsures(Proc, expr);

-            }

-        }

-

-

-

-    }

-

-

-

-    class FindReferencesToNamedVariableVisitor : StandardVisitor

-    {

-        internal bool found = false;

-        private string name;

-

-        internal FindReferencesToNamedVariableVisitor(string name)

-        {

-            this.name = name;

-        }

-

-        public override Variable VisitVariable(Variable node)

-        {

-            if (GPUVerifier.StripThreadIdentifier(node.Name).Equals(name))

-            {

-                found = true;

-            }

-            return base.VisitVariable(node);

-        }

-    }

-

-

-

-}

diff --git a/Source/GPUVerify/ReducedStrengthAnalysis.cs b/Source/GPUVerify/ReducedStrengthAnalysis.cs
deleted file mode 100644
index 0e58ff7d..00000000
--- a/Source/GPUVerify/ReducedStrengthAnalysis.cs
+++ /dev/null
@@ -1,166 +0,0 @@
-using Microsoft.Boogie;
-using System;
-using System.Collections.Generic;
-using System.Linq;
-
-namespace GPUVerify {
-
-class ReducedStrengthAnalysis {
-
-  GPUVerifier verifier;
-  Implementation impl;
-  VariableDefinitionAnalysis varDefs;
-
-  Dictionary<Variable, List<Tuple<object, Expr>>> multiDefMap = new Dictionary<Variable, List<Tuple<object, Expr>>>();
-  Dictionary<string, ModStrideConstraint> strideConstraintMap = new Dictionary<string, ModStrideConstraint>();
-  Dictionary<object, List<string>> loopCounterMap = new Dictionary<object, List<string>>();
-
-  ReducedStrengthAnalysis(GPUVerifier v, Implementation i) {
-    verifier = v;
-    impl = i;
-    varDefs = verifier.varDefAnalyses[impl];
-  }
-
-  void AddAssignment(object regionId, AssignLhs lhs, Expr rhs) {
-    if (lhs is SimpleAssignLhs) {
-      var sLhs = (SimpleAssignLhs)lhs;
-      var theVar = sLhs.DeepAssignedVariable;
-      List<Tuple<object, Expr>> defs;
-      if (multiDefMap.ContainsKey(theVar))
-        defs = multiDefMap[theVar];
-      else
-        defs = multiDefMap[theVar] = new List<Tuple<object, Expr>>();
-      defs.Add(new Tuple<object, Expr>(regionId, rhs));
-    }
-  }
-
-  void AnalyseRegion(IRegion region) {
-    foreach (var c in region.CmdsChildRegions()) {
-      var ac = c as AssignCmd;
-      if (ac != null) {
-        foreach (var a in ac.Lhss.Zip(ac.Rhss)) {
-          AddAssignment(region.Identifier(), a.Item1, a.Item2);
-        }
-      }
-      var child = c as IRegion;
-      if (child != null)
-        AnalyseRegion(child);
-    }
-  }
-
-  void Analyse() {
-    AnalyseRegion(verifier.RootRegion(impl));
-    foreach (var v in multiDefMap.Keys) {
-      var defs = multiDefMap[v];
-      if (defs.Count != 2)
-        continue;
-      bool def0IsConst, def1IsConst;
-      var def0 = varDefs.SubstDefinitions(defs[0].Item2, impl.Name, out def0IsConst);
-      var def1 = varDefs.SubstDefinitions(defs[1].Item2, impl.Name, out def1IsConst);
-      if (def0IsConst && !def1IsConst) {
-        AddDefinitionPair(v, def0, def1, defs[1].Item1);
-      } else if (!def0IsConst && def1IsConst) {
-        AddDefinitionPair(v, def1, def0, defs[0].Item1);
-      }
-    }
-    multiDefMap = null;
-  }
-
-  private class StrideForm {
-    public StrideForm(Kind kind) { this.kind = kind; this.op = null; }
-    public StrideForm(Kind kind, Expr op) { this.kind = kind; this.op = op; }
-    public enum Kind { Bottom, Identity, Constant, Product, PowerMul, PowerDiv };
-    public Kind kind;
-    public Expr op;
-  }
-
-  private StrideForm ComputeStrideForm(Variable v, Expr e) {
-    Expr lhs, rhs;
-
-    if (e is LiteralExpr)
-      return new StrideForm(StrideForm.Kind.Constant, e);
-
-    var ie = e as IdentifierExpr;
-    if (ie != null) {
-      if (ie.Decl is Constant)
-        return new StrideForm(StrideForm.Kind.Constant, e);
-      if (ie.Decl == v)
-        return new StrideForm(StrideForm.Kind.Identity, e);
-    }
-
-    if (GPUVerifier.IsBVAdd(e, out lhs, out rhs)) {
-      var lhssf = ComputeStrideForm(v, lhs);
-      var rhssf = ComputeStrideForm(v, rhs);
-      if (lhssf.kind == StrideForm.Kind.Constant &&
-          rhssf.kind == StrideForm.Kind.Constant)
-        return new StrideForm(StrideForm.Kind.Constant, e);
-      else if (lhssf.kind == StrideForm.Kind.Constant &&
-               rhssf.kind == StrideForm.Kind.Identity)
-        return new StrideForm(StrideForm.Kind.Product, lhs);
-      else if (lhssf.kind == StrideForm.Kind.Identity &&
-               rhssf.kind == StrideForm.Kind.Constant)
-        return new StrideForm(StrideForm.Kind.Product, rhs);
-      else if (lhssf.kind == StrideForm.Kind.Constant &&
-               rhssf.kind == StrideForm.Kind.Product)
-        return new StrideForm(StrideForm.Kind.Product, verifier.MakeBVAdd(lhs, rhssf.op));
-      else if (lhssf.kind == StrideForm.Kind.Product &&
-               rhssf.kind == StrideForm.Kind.Constant)
-        return new StrideForm(StrideForm.Kind.Product, verifier.MakeBVAdd(lhssf.op, rhs));
-      else
-        return new StrideForm(StrideForm.Kind.Bottom);
-    }
-
-    var ne = e as NAryExpr;
-    if (ne != null) {
-      foreach (Expr op in ne.Args)
-        if (ComputeStrideForm(v, op).kind != StrideForm.Kind.Constant)
-          return new StrideForm(StrideForm.Kind.Bottom);
-      return new StrideForm(StrideForm.Kind.Constant, e);
-    }
-
-    return new StrideForm(StrideForm.Kind.Bottom);
-  }
-
-  private void AddDefinitionPair(Variable v, Expr constDef, Expr nonConstDef, object nonConstId) {
-    var sf = ComputeStrideForm(v, nonConstDef);
-    if (sf.kind == StrideForm.Kind.Product) {
-      var sc = new ModStrideConstraint(sf.op, constDef);
-      if (!sc.IsBottom()) {
-        strideConstraintMap[v.Name] = sc;
-        List<string> lcs;
-        if (loopCounterMap.ContainsKey(nonConstId))
-          lcs = loopCounterMap[nonConstId];
-        else
-          lcs = loopCounterMap[nonConstId] = new List<string>();
-        lcs.Add(v.Name);
-      }
-    }
-  }
-
-  public StrideConstraint GetStrideConstraint(string varName) {
-    int id;
-    var strippedVarName = GPUVerifier.StripThreadIdentifier(varName, out id);
-    if (!strideConstraintMap.ContainsKey(strippedVarName))
-      return null;
-
-    var msc = strideConstraintMap[strippedVarName];
-    if (id == 0)
-      return msc;
-    return new ModStrideConstraint(verifier.MaybeDualise(msc.mod, id, impl.Name),
-                                   verifier.MaybeDualise(msc.modEq, id, impl.Name));
-  }
-
-  public IEnumerable<string> StridedLoopCounters(object loopId) {
-    if (!loopCounterMap.ContainsKey(loopId))
-      return Enumerable.Empty<string>();
-    return loopCounterMap[loopId];
-  }
-
-  public static ReducedStrengthAnalysis Analyse(GPUVerifier verifier, Implementation impl) {
-    var a = new ReducedStrengthAnalysis(verifier, impl);
-    a.Analyse();
-    return a;
-  }
-}
-
-}
diff --git a/Source/GPUVerify/StrideConstraint.cs b/Source/GPUVerify/StrideConstraint.cs
deleted file mode 100755
index 948786b7..00000000
--- a/Source/GPUVerify/StrideConstraint.cs
+++ /dev/null
@@ -1,141 +0,0 @@
-using System;

-using System.Collections.Generic;

-using System.Linq;

-using System.Text;

-using Microsoft.Basetypes;

-using Microsoft.Boogie;

-

-namespace GPUVerify {

-

-class StrideConstraint {

-

-  public static StrideConstraint Bottom(Expr e) {

-    int width = e.Type.BvBits;

-    return new ModStrideConstraint(new LiteralExpr(Token.NoToken, BigNum.FromInt(1), width),

-                                   new LiteralExpr(Token.NoToken, BigNum.FromInt(0), width));

-  }

-

-  public bool IsBottom() {

-    var msc = this as ModStrideConstraint;

-    if (msc == null)

-        return false;

-

-    var le = msc.mod as LiteralExpr;

-    if (le == null)

-        return false;

-

-    var bvc = le.Val as BvConst;

-    if (bvc == null)

-        return false;

-

-    return bvc.Value.InInt32 && bvc.Value.ToInt == 1;

-  }

-

-  private Expr ExprModPow2(GPUVerifier verifier, Expr expr, Expr powerOfTwoExpr) {

-    Expr Pow2Minus1 = verifier.MakeBVSub(powerOfTwoExpr, 

-                                         new LiteralExpr(Token.NoToken, BigNum.FromInt(1), 32));

-

-    return verifier.MakeBVAnd(Pow2Minus1, expr);

-  }

-

-  public Expr MaybeBuildPredicate(GPUVerifier verifier, Expr e) {

-    var msc = this as ModStrideConstraint;

-    if (msc != null && !msc.IsBottom()) {

-      Expr modEqExpr = Expr.Eq(ExprModPow2(verifier, e, msc.mod), ExprModPow2(verifier, msc.modEq, msc.mod));

-      return modEqExpr;

-    }

-

-    return null;

-  }

-

-  private static StrideConstraint BuildAddStrideConstraint(GPUVerifier verifier, Expr e, StrideConstraint lhsc, StrideConstraint rhsc) {

-    if (lhsc is EqStrideConstraint && rhsc is EqStrideConstraint) {

-      return new EqStrideConstraint(e);

-    }

-

-    if (lhsc is EqStrideConstraint && rhsc is ModStrideConstraint)

-      return BuildAddStrideConstraint(verifier, e, rhsc, lhsc);

-

-    if (lhsc is ModStrideConstraint && rhsc is EqStrideConstraint) {

-      var lhsmc = (ModStrideConstraint)lhsc;

-      var rhsec = (EqStrideConstraint)rhsc;

-

-      return new ModStrideConstraint(lhsmc.mod, verifier.MakeBVAdd(lhsmc.modEq, rhsec.eq));

-    }

-

-    if (lhsc is ModStrideConstraint && rhsc is ModStrideConstraint) {

-      var lhsmc = (ModStrideConstraint)lhsc;

-      var rhsmc = (ModStrideConstraint)rhsc;

-

-      if (lhsmc.mod == rhsmc.mod)

-        return new ModStrideConstraint(lhsmc.mod, verifier.MakeBVAdd(lhsmc.modEq, rhsmc.modEq));

-    }

-

-    return Bottom(e);

-  }

-

-  private static StrideConstraint BuildMulStrideConstraint(GPUVerifier verifier, Expr e, StrideConstraint lhsc, StrideConstraint rhsc) {

-    if (lhsc is EqStrideConstraint && rhsc is EqStrideConstraint) {

-      return new EqStrideConstraint(e);

-    }

-

-    if (lhsc is EqStrideConstraint && rhsc is ModStrideConstraint)

-      return BuildMulStrideConstraint(verifier, e, rhsc, lhsc);

-

-    if (lhsc is ModStrideConstraint && rhsc is EqStrideConstraint) {

-      var lhsmc = (ModStrideConstraint)lhsc;

-      var rhsec = (EqStrideConstraint)rhsc;

-

-      return new ModStrideConstraint(verifier.MakeBVMul(lhsmc.mod, rhsec.eq),

-                                     verifier.MakeBVMul(lhsmc.modEq, rhsec.eq));

-    }

-

-    return Bottom(e);

-  }

-

-  public static StrideConstraint FromExpr(GPUVerifier verifier, Implementation impl, Expr e) {

-    if (e is LiteralExpr)

-      return new EqStrideConstraint(e);

-

-    var ie = e as IdentifierExpr;

-    if (ie != null) {

-      if (ie.Decl is Constant)

-        return new EqStrideConstraint(e);

-

-      var rsa = verifier.reducedStrengthAnalyses[impl];

-      var sc = rsa.GetStrideConstraint(ie.Decl.Name);

-      if (sc == null)

-        return Bottom(e);

-      return sc;

-    }

-

-    Expr lhs, rhs;

-

-    if (GPUVerifier.IsBVAdd(e, out lhs, out rhs)) {

-      var lhsc = FromExpr(verifier, impl, lhs);

-      var rhsc = FromExpr(verifier, impl, rhs);

-      return BuildAddStrideConstraint(verifier, e, lhsc, rhsc);

-    }

-

-    if (GPUVerifier.IsBVMul(e, out lhs, out rhs)) {

-      var lhsc = FromExpr(verifier, impl, lhs);

-      var rhsc = FromExpr(verifier, impl, rhs);

-      return BuildMulStrideConstraint(verifier, e, lhsc, rhsc);

-    }

-

-    return Bottom(e);

-  }

-

-}

-

-class EqStrideConstraint : StrideConstraint {

-  public EqStrideConstraint(Expr eq) { this.eq = eq; }

-  public Expr eq;

-}

-

-class ModStrideConstraint : StrideConstraint {

-  public ModStrideConstraint(Expr mod, Expr modEq) { this.mod = mod; this.modEq = modEq; }

-  public Expr mod, modEq;

-}

-

-}

diff --git a/Test/dafny0/Answer b/Test/dafny0/Answer
index 7510363a..85958099 100644
--- a/Test/dafny0/Answer
+++ b/Test/dafny0/Answer
@@ -703,8 +703,8 @@ Execution trace:
 Dafny program verifier finished with 7 verified, 1 error

 

 -------------------- ModulesCycle.dfy --------------------

-ModulesCycle.dfy(12,7): Error: module T named among imports does not exist

-ModulesCycle.dfy(23,7): Error: import graph contains a cycle: H -> I -> J -> G

+ModulesCycle.dfy(3,9): Error: module T does not exist

+ModulesCycle.dfy(6,7): Error: module definition contains a cycle (note: parent modules implicitly depend on submodules): A -> D -> C -> B

 2 resolution/type errors detected in ModulesCycle.dfy

 

 -------------------- Modules0.dfy --------------------

@@ -714,55 +714,47 @@ Modules0.dfy(7,7): Error: Duplicate name of top-level declaration: WazzupA
 Modules0.dfy(10,7): Error: Duplicate name of top-level declaration: WazzupB

 Modules0.dfy(11,8): Error: Duplicate name of top-level declaration: WazzupB

 Modules0.dfy(12,11): Error: Duplicate name of top-level declaration: WazzupB

-Modules0.dfy(42,11): Error: The name T ambiguously refers to a type in one of the modules N, M (try qualifying the type name with the module name)

-Modules0.dfy(43,18): Error: The name T ambiguously refers to a type in one of the modules N, M (try qualifying the type name with the module name)

-Modules0.dfy(44,15): Error: The name T ambiguously refers to a type in one of the modules N, M (try qualifying the type name with the module name)

-Modules0.dfy(46,16): Error: The name T ambiguously refers to a type in one of the modules N, M (try qualifying the type name with the module name)

-Modules0.dfy(47,18): Error: The name T ambiguously refers to a type in one of the modules N, M (try qualifying the type name with the module name)

-Modules0.dfy(52,19): Error: The name T ambiguously refers to a type in one of the modules N, M (try qualifying the type name with the module name)

-Modules0.dfy(52,12): Error: new can be applied only to reference types (got T)

-Modules0.dfy(57,12): Error: Undeclared top-level type or type parameter: T (did you forget a module import?)

-Modules0.dfy(73,18): Error: Undeclared top-level type or type parameter: MyClass1 (did you forget a module import?)

-Modules0.dfy(74,18): Error: Undeclared top-level type or type parameter: MyClass2 (did you forget a module import?)

-Modules0.dfy(84,18): Error: Undeclared top-level type or type parameter: MyClass2 (did you forget a module import?)

-Modules0.dfy(108,16): Error: Undeclared top-level type or type parameter: ClassG (did you forget a module import?)

-Modules0.dfy(247,11): Error: Undeclared top-level type or type parameter: X (did you forget a module import?)

-Modules0.dfy(256,13): Error: unresolved identifier: X

-Modules0.dfy(257,15): Error: member DoesNotExist does not exist in class X

-Modules0.dfy(299,16): Error: member R does not exist in class B

-Modules0.dfy(299,6): Error: expected method call, found expression

-Modules0.dfy(322,18): Error: second argument to "in" must be a set or sequence with elements of type Q_Imp.Node, or a map with domain Q_Imp.Node (instead got set<Node>)

-Modules0.dfy(326,13): Error: arguments must have the same type (got Q_Imp.Node and Node)

-Modules0.dfy(327,11): Error: Undeclared module name: LongLostModule (did you forget a module import?)

-Modules0.dfy(328,11): Error: Undeclared module name: Wazzup (did you forget a module import?)

-Modules0.dfy(329,17): Error: Undeclared class name Edon in module Q_Imp

-Modules0.dfy(331,10): Error: new can be applied only to reference types (got Q_Imp.List<?>)

-Modules0.dfy(332,30): Error: member Create does not exist in class Klassy

-Modules0.dfy(143,11): Error: ghost variables are allowed only in specification contexts

-Modules0.dfy(157,11): Error: old expressions are allowed only in specification and ghost contexts

-Modules0.dfy(158,11): Error: fresh expressions are allowed only in specification and ghost contexts

-Modules0.dfy(159,11): Error: allocated expressions are allowed only in specification and ghost contexts

-Modules0.dfy(175,10): Error: match source expression 'tree' has already been used as a match source expression in this context

-Modules0.dfy(214,12): Error: match source expression 'l' has already been used as a match source expression in this context

-36 resolution/type errors detected in Modules0.dfy

+Modules0.dfy(53,18): Error: Undeclared top-level type or type parameter: MyClass1 (did you forget a module import?)

+Modules0.dfy(54,18): Error: Undeclared top-level type or type parameter: MyClass2 (did you forget a module import?)

+Modules0.dfy(65,18): Error: Undeclared top-level type or type parameter: MyClass2 (did you forget a module import?)

+Modules0.dfy(72,20): Error: Undeclared top-level type or type parameter: MyClass1 (did you forget a module import?)

+Modules0.dfy(72,34): Error: Undeclared top-level type or type parameter: MyClass0 (did you forget a module import?)

+Modules0.dfy(75,23): Error: Undeclared top-level type or type parameter: MyClass0 (did you forget a module import?)

+Modules0.dfy(80,24): Error: Undeclared top-level type or type parameter: MyClassY (did you forget a module import?)

+Modules0.dfy(89,16): Error: Undeclared top-level type or type parameter: ClassG (did you forget a module import?)

+Modules0.dfy(221,15): Error: Undeclared top-level type or type parameter: X (did you forget a module import?)

+Modules0.dfy(221,8): Error: new can be applied only to reference types (got X)

+Modules0.dfy(230,13): Error: The name does not exist in the given module

+Modules0.dfy(240,13): Error: unresolved identifier: X

+Modules0.dfy(241,15): Error: member DoesNotExist does not exist in class X

+Modules0.dfy(280,19): Error: Undeclared top-level type or type parameter: D (did you forget a module import?)

+Modules0.dfy(280,12): Error: new can be applied only to reference types (got D)

+Modules0.dfy(283,25): Error: type of the receiver is not fully determined at this program point

+Modules0.dfy(284,16): Error: type of the receiver is not fully determined at this program point

+Modules0.dfy(284,6): Error: expected method call, found expression

+Modules0.dfy(285,16): Error: type of the receiver is not fully determined at this program point

+Modules0.dfy(285,6): Error: expected method call, found expression

+Modules0.dfy(307,24): Error: Undeclared module name: Q_Imp (did you forget a module import?)

+Modules0.dfy(97,14): Error: Undeclared top-level type or type parameter: MyClassY (did you forget a module import?)

+28 resolution/type errors detected in Modules0.dfy

 

 -------------------- Modules1.dfy --------------------

-Modules1.dfy(74,16): Error: assertion violation

+Modules1.dfy(75,16): Error: assertion violation

 Execution trace:

     (0,0): anon0

     (0,0): anon3_Then

-Modules1.dfy(86,16): Error: assertion violation

+Modules1.dfy(88,16): Error: assertion violation

 Execution trace:

     (0,0): anon0

     (0,0): anon3_Then

-Modules1.dfy(88,14): Error: assertion violation

+Modules1.dfy(90,14): Error: assertion violation

 Execution trace:

     (0,0): anon0

     (0,0): anon3_Else

-Modules1.dfy(52,3): Error: decreases expression must be bounded below by 0

+Modules1.dfy(53,3): Error: decreases expression must be bounded below by 0

 Execution trace:

     (0,0): anon0

-Modules1.dfy(58,3): Error: failure to decrease termination measure

+Modules1.dfy(59,3): Error: failure to decrease termination measure

 Execution trace:

     (0,0): anon0

 

@@ -1441,19 +1433,19 @@ Refinement.dfy(93,3): Error BP5003: A postcondition might not hold on this retur
 Refinement.dfy(74,15): Related location: This is the postcondition that might not hold.

 Execution trace:

     (0,0): anon0

-Refinement.dfy(179,5): Error BP5003: A postcondition might not hold on this return path.

+Refinement.dfy(180,5): Error BP5003: A postcondition might not hold on this return path.

 Refinement.dfy(112,15): Related location: This is the postcondition that might not hold.

-Refinement.dfy(176,9): Related location: Related location

+Refinement.dfy(177,9): Related location: Related location

 Execution trace:

     (0,0): anon0

-Refinement.dfy(183,5): Error BP5003: A postcondition might not hold on this return path.

+Refinement.dfy(184,5): Error BP5003: A postcondition might not hold on this return path.

 Refinement.dfy(120,15): Related location: This is the postcondition that might not hold.

-Refinement.dfy(176,9): Related location: Related location

+Refinement.dfy(177,9): Related location: Related location

 Execution trace:

     (0,0): anon0

     (0,0): anon4_Then

     (0,0): anon3

-Refinement.dfy(189,7): Error: assertion violation

+Refinement.dfy(190,7): Error: assertion violation

 Refinement.dfy[IncorrectConcrete](128,24): Related location: Related location

 Execution trace:

     (0,0): anon0

@@ -1535,24 +1527,24 @@ Predicates.dfy[B](17,15): Related location: This is the postcondition that might
 Predicates.dfy(28,9): Related location: Related location

 Execution trace:

     (0,0): anon0

-Predicates.dfy(84,16): Error: assertion violation

+Predicates.dfy(85,16): Error: assertion violation

 Execution trace:

     (0,0): anon0

-Predicates.dfy(88,14): Error: assertion violation

+Predicates.dfy(89,14): Error: assertion violation

 Execution trace:

     (0,0): anon0

-Predicates.dfy[Tricky_Full](121,5): Error BP5003: A postcondition might not hold on this return path.

-Predicates.dfy[Tricky_Full](120,15): Related location: This is the postcondition that might not hold.

-Predicates.dfy(131,7): Related location: Related location

-Predicates.dfy[Tricky_Full](111,9): Related location: Related location

+Predicates.dfy[Tricky_Full](123,5): Error BP5003: A postcondition might not hold on this return path.

+Predicates.dfy[Tricky_Full](122,15): Related location: This is the postcondition that might not hold.

+Predicates.dfy(133,7): Related location: Related location

+Predicates.dfy[Tricky_Full](113,9): Related location: Related location

 Execution trace:

     (0,0): anon0

-Predicates.dfy(159,5): Error BP5003: A postcondition might not hold on this return path.

-Predicates.dfy(158,15): Related location: This is the postcondition that might not hold.

+Predicates.dfy(161,5): Error BP5003: A postcondition might not hold on this return path.

+Predicates.dfy(160,15): Related location: This is the postcondition that might not hold.

 Execution trace:

     (0,0): anon0

-Predicates.dfy[Q1](149,5): Error BP5003: A postcondition might not hold on this return path.

-Predicates.dfy[Q1](148,15): Related location: This is the postcondition that might not hold.

+Predicates.dfy[Q1](151,5): Error BP5003: A postcondition might not hold on this return path.

+Predicates.dfy[Q1](150,15): Related location: This is the postcondition that might not hold.

 Execution trace:

     (0,0): anon0

 

@@ -1583,9 +1575,10 @@ Execution trace:
 Dafny program verifier finished with 30 verified, 2 errors

 

 -------------------- LiberalEquality.dfy --------------------

+LiberalEquality.dfy(18,14): Error: arguments must have the same type (got T and U)

 LiberalEquality.dfy(37,14): Error: arguments must have the same type (got Weird<T,int,V> and Weird<T,bool,V>)

 LiberalEquality.dfy(52,14): Error: arguments must have the same type (got array<int> and array<bool>)

-2 resolution/type errors detected in LiberalEquality.dfy

+3 resolution/type errors detected in LiberalEquality.dfy

 

 -------------------- SmallTests.dfy --------------------

 SmallTests.dfy(30,11): Error: index out of range

diff --git a/Test/dafny0/LiberalEquality.dfy b/Test/dafny0/LiberalEquality.dfy
index 3dc52c80..b9b4629b 100644
--- a/Test/dafny0/LiberalEquality.dfy
+++ b/Test/dafny0/LiberalEquality.dfy
@@ -15,7 +15,7 @@ class Test<T> {
 }

 

 method m1<T, U>(t: T, u: U)

-   requires t != u;

+   requires t != u; // Cannot compare type parameters (can only compare reference types that could be the same)

 {

    

 }

diff --git a/Test/dafny0/Modules0.dfy b/Test/dafny0/Modules0.dfy
index 80ac7eef..273c88de 100644
--- a/Test/dafny0/Modules0.dfy
+++ b/Test/dafny0/Modules0.dfy
@@ -23,46 +23,26 @@ module N {
   class T { }

 }

 

-module U imports N {  // fine, despite the fact that a class is called U,

-                      // since module names are in their own name space

+module U {

+  module NN = N;

 }

 

-module UU imports N, U, N, N {  // duplicates are allowed

-}

-

-module N_left imports N { }

-module N_right imports N { }

-module Diamond imports N_left, N_right {  // this imports N.T twice, but that's okay

-}

 

-module A imports N, M {  // Note, this has the effect of importing two different T's,

-                         // but that's okay as long as the module doesn't try to access

-                         // one of them

+module A {  // Note, this has the effect of importing two different T's,

+            // but that's okay as long as the module doesn't try to access

+            // one of them

+  module MM = M;

+  module NN = N;

   class X {

-    var t: T;  // error: use of the ambiguous name T

-    function F(x: T):  // error: use of the ambiguous name T

-               T  // error: use of the ambiguous name T

+    var t: MM.T;  // error: use of the ambiguous name T

+    function F(x: MM.T):  // error: use of the ambiguous name T

+               MM.T  // error: use of the ambiguous name T

     { x }

-    method M(x: T)  // error: use of the ambiguous name T

-      returns (y: T)  // error: use of the ambiguous name T

+    method M(x: NN.T)  // error: use of the ambiguous name T

+      returns (y: NN.T)  // error: use of the ambiguous name T

   }

 }

-module A' imports N, M {

-  method M()

-    { var g := new T; }  // error: use of the ambiguous name T

-}

 

-module B0 imports A {

-  class BadUse {

-    var b0: T;  // error: T is not directly accessible

-  }

-}

-

-module B1 imports A, N {

-  class GoodUse {

-    var b1: T;  // fine

-  }

-}

 

 // --------------- calls

 

@@ -76,9 +56,10 @@ module X0 {
   }

 }

 

-module X1 imports X0 {

+module X1 {

+  module X0' = X0;

   class MyClass1 {

-    method Down(x0: MyClass0) {

+    method Down(x0: X0'.MyClass0) {

       x0.Down();

     }

     method Up(x2: MyClass2) {  // error: class MyClass2 is not in scope

@@ -86,7 +67,7 @@ module X1 imports X0 {
   }

 }

 

-module X2 imports X0, X1, YY {

+module X2 {

   class MyClass2 {

     method Down(x1: MyClass1, x0: MyClass0) {

       x1.Down(x0);

@@ -231,9 +212,10 @@ module ATr {
   }

 }

 

-module BTr imports ATr {

+module BTr {

+  module A = ATr;

   class Y {

-    method N() returns (x: X)

+    method N() returns (x: A.X)

       ensures x != null;

     {

       x := new X;

@@ -241,15 +223,17 @@ module BTr imports ATr {
   }

 }

 

-module CTr imports BTr {

+module CTr {

+  module B = BTr;

   class Z {

-    var b: Y;  // fine

-    var a: X;  // error: imports don't reach name X explicitly

+    var b: B.Y;  // fine

+    var a: B.X;  // error: imports don't reach name X explicitly

   }

 }

-module CTs imports BTr {

+module CTs {

+  module B = BTr;

   method P() {

-    var y := new Y;

+    var y := new B.Y;

     var x := y.N();  // this is allowed and will correctly infer the type of x to

                      // be X, but X could not have been mentioned explicitly

     var q := x.M();

@@ -285,7 +269,9 @@ module NonLocalB {
   }

 }

 

-module Local imports NonLocalA, NonLocalB {

+module Local {

+  module AA = NonLocalA;

+  module BB = NonLocalB;

   class MyClass {

     method MyMethod()

     {

@@ -317,7 +303,7 @@ module Q_Imp {
   }

 }

 

-module Q_M imports Q_Imp {

+module Q_M {

   method MyMethod(root: Q_Imp.Node, S: set<Node>)

     requires root in S;  // error: the element type of S does not agree with the type of root

   {

diff --git a/Test/dafny0/Modules1.dfy b/Test/dafny0/Modules1.dfy
index e8a88749..6fd8560e 100644
--- a/Test/dafny0/Modules1.dfy
+++ b/Test/dafny0/Modules1.dfy
@@ -1,6 +1,7 @@
-module A imports B {

+module A {

+  module B = Babble;

   class X {

-    function Fx(z: Z): int

+    function Fx(z: B.Z): int

       requires z != null;

       decreases 5, 4, 3;

     { z.G() }  // fine; this goes to a different module

@@ -17,7 +18,7 @@ method MyMethod() { }
 

 var MyField: int;

 

-module B {

+module Babble {

   class Z {

     method K() { }

     function G(): int

@@ -78,14 +79,15 @@ module A_Visibility {
   }

 }

 

-module B_Visibility imports A_Visibility {

+module B_Visibility {

+  module A = A_Visibility;

   method Main() {

     var y;

-    if (C.P(y)) {

+    if (A.C.P(y)) {

       assert 0 <= y;  // this much is known of C.P

       assert 2 <= y;  // error

     } else {

-      assert C.P(8);  // error: C.P cannot be established outside the declaring module

+      assert A.C.P(8);  // error: C.P cannot be established outside the declaring module

     }

   }

 }

@@ -99,13 +101,14 @@ module Q_Imp {
   }

 }

 

-module Q_M imports Q_Imp {

-  method MyMethod(root: Q_Imp.Node, S: set<Q_Imp.Node>)

+module Q_M {

+  module Q = Q_Imp;

+  method MyMethod(root: Q.Node, S: set<Q.Node>)

     requires root in S;

   {

-    var i := new Q_Imp.Node;

-    var j := new Node;

+    var i := new Q.Node;

+    var j := new Q.Node;

     assert i != j;  // fine

-    var q := new Q_Imp.Klassy.Init();

+    var q := new Q.Klassy.Init();

   }

 }

diff --git a/Test/dafny0/ModulesCycle.dfy b/Test/dafny0/ModulesCycle.dfy
index a7f1caa2..15cad8e8 100644
--- a/Test/dafny0/ModulesCycle.dfy
+++ b/Test/dafny0/ModulesCycle.dfy
@@ -1,33 +1,12 @@
-module M {

-  class T { }

-  class U { }

-}

-

-module N {

-}

-

-module U imports N {

-}

-

-module V imports T {  // error: T is not a module

-}

 

-module A imports B, M {

-  class Y { }

+module V {

+  module t = T;  // error: T is not visible (and isn't even a module)

 }

 

-module B imports N, M {

-  class X { }

+module A {

+  module B = C;

 }

 

-module G imports A, M, A, H, B {  // error: cycle in import graph

-}

-

-module H imports A, N, I {

-}

-

-module I imports J {

-}

-

-module J imports G, M {

-}

+module C {

+  module D = A;

+}
\ No newline at end of file
diff --git a/Test/dafny0/Predicates.dfy b/Test/dafny0/Predicates.dfy
index 146129b5..8857482f 100644
--- a/Test/dafny0/Predicates.dfy
+++ b/Test/dafny0/Predicates.dfy
@@ -78,9 +78,10 @@ module Tight refines Loose {
   }

 }

 

-module UnawareClient imports Loose {

+module UnawareClient {

+  module L = Loose;

   method Main0() {

-    var n := new MyNumber.Init();

+    var n := new L.MyNumber.Init();

     assert n.N == 0;  // error: this is not known

     n.Inc();

     n.Inc();

@@ -89,9 +90,10 @@ module UnawareClient imports Loose {
   }

 }

 

-module AwareClient imports Tight {

+module AwareClient {

+  module T = Tight;

   method Main1() {

-    var n := new MyNumber.Init();

+    var n := new T.MyNumber.Init();

     assert n.N == 0;

     n.Inc();

     n.Inc();

diff --git a/Test/dafny0/Refinement.dfy b/Test/dafny0/Refinement.dfy
index da7f0ac2..2c2fc52b 100644
--- a/Test/dafny0/Refinement.dfy
+++ b/Test/dafny0/Refinement.dfy
@@ -155,10 +155,11 @@ module Concrete refines Abstract {
   }
 }
 
-module Client imports Concrete {
+module Client {
+  module C = Concrete;
   class TheClient {
     method Main() {
-      var n := new MyNumber.Init();
+      var n := new C.MyNumber.Init();
       n.Inc();
       n.Inc();
       var k := n.Get();
diff --git a/Test/dafny1/Answer b/Test/dafny1/Answer
index 06cac03b..b2876948 100644
--- a/Test/dafny1/Answer
+++ b/Test/dafny1/Answer
@@ -11,10 +11,6 @@ Dafny program verifier finished with 24 verified, 0 errors
 

 Dafny program verifier finished with 11 verified, 0 errors

 

--------------------- ExtensibleArrayAuto.dfy --------------------

-

-Dafny program verifier finished with 11 verified, 0 errors

-

 -------------------- BinaryTree.dfy --------------------

 

 Dafny program verifier finished with 24 verified, 0 errors

diff --git a/Test/dafny1/ListContents.dfy b/Test/dafny1/ListContents.dfy
index 594be748..a8b4861d 100644
--- a/Test/dafny1/ListContents.dfy
+++ b/Test/dafny1/ListContents.dfy
@@ -62,7 +62,7 @@ class Node<T> {
     reverse.next := null;

     reverse.footprint := {reverse};

     reverse.list := [data];

-

+    

     while (current != null)

       invariant reverse != null && reverse.Valid();

       invariant reverse.footprint <= old(footprint);

@@ -71,8 +71,8 @@ class Node<T> {
         current.Valid() &&

         current in old(footprint) && current.footprint <= old(footprint) &&

         current.footprint !! reverse.footprint &&

-        |old(list)| == |reverse.list| + |current.list| &&

-        (forall i :: 0 <= i && i < |current.list| ==> current.list[i] == old(list)[|reverse.list|+i]);

+        |old(list)| == |reverse.list| + |current.list|;

+      invariant current != null ==> current.list == old(list)[|reverse.list|..];

       invariant

         (forall i :: 0 <= i && i < |reverse.list| ==> old(list)[i] == reverse.list[|reverse.list|-1-i]);

       decreases if current != null then |current.list| else -1;

@@ -86,13 +86,6 @@ class Node<T> {
 

       reverse := current;

       current := nx;

-	  // This makes the verification go faster.

-	  assert current != null ==>

-        current.Valid() &&

-        current in old(footprint) && current.footprint <= old(footprint) &&

-        current.footprint !! reverse.footprint &&

-        |old(list)| == |reverse.list| + |current.list| &&

-        (forall i :: 0 <= i && i < |current.list| ==> current.list[i] == old(list)[|reverse.list|+i]);

     }

   }

 }

diff --git a/Test/dafny1/runtest.bat b/Test/dafny1/runtest.bat
index fa7f7c70..22bef761 100644
--- a/Test/dafny1/runtest.bat
+++ b/Test/dafny1/runtest.bat
@@ -5,7 +5,7 @@ set BOOGIEDIR=..\..\Binaries
 set DAFNY_EXE=%BOOGIEDIR%\Dafny.exe

 

 for %%f in (Queue.dfy PriorityQueue.dfy

-            ExtensibleArray.dfy ExtensibleArrayAuto.dfy

+            ExtensibleArray.dfy

             BinaryTree.dfy

             UnboundedStack.dfy

             SeparationLogicList.dfy

diff --git a/Test/dafny2/Answer b/Test/dafny2/Answer
index 9c37549e..f359e416 100644
--- a/Test/dafny2/Answer
+++ b/Test/dafny2/Answer
@@ -39,10 +39,6 @@ Dafny program verifier finished with 3 verified, 0 errors
 

 Dafny program verifier finished with 3 verified, 0 errors

 

--------------------- StoreAndRetrieve.dfy --------------------

-

-Dafny program verifier finished with 22 verified, 0 errors

-

 -------------------- MajorityVote.dfy --------------------

 

 Dafny program verifier finished with 11 verified, 0 errors

diff --git a/Test/dafny2/runtest.bat b/Test/dafny2/runtest.bat
index b68ba251..19b116d2 100644
--- a/Test/dafny2/runtest.bat
+++ b/Test/dafny2/runtest.bat
@@ -4,7 +4,7 @@ setlocal
 set BOOGIEDIR=..\..\Binaries

 set DAFNY_EXE=%BOOGIEDIR%\Dafny.exe

 

-REM soon again:    SnapshotableTrees.dfy 

+REM soon again:    SnapshotableTrees.dfy StoreAndRetrieve.dfy

 for %%f in (

     Classics.dfy

     TreeBarrier.dfy

@@ -14,7 +14,7 @@ for %%f in (
     COST-verif-comp-2011-3-TwoDuplicates.dfy

     COST-verif-comp-2011-4-FloydCycleDetect.dfy

     Intervals.dfy TreeFill.dfy TuringFactorial.dfy

-    StoreAndRetrieve.dfy MajorityVote.dfy SegmentSum.dfy

+    MajorityVote.dfy SegmentSum.dfy

   ) do (

   echo.

   echo -------------------- %%f --------------------

diff --git a/Test/test15/Answer b/Test/test15/Answer
index 04a94759..473af09b 100644
--- a/Test/test15/Answer
+++ b/Test/test15/Answer
@@ -1,14 +1,14 @@
 

 -------------------- NullInModel --------------------

 *** MODEL

-s -> T@U!val!0

-%lbl%+24 -> true

 %lbl%@47 -> false

-refType -> T@T!val!2

-intType -> T@T!val!0

+%lbl%+24 -> true

 %lbl%+37 -> true

 boolType -> T@T!val!1

+intType -> T@T!val!0

 null -> T@U!val!0

+refType -> T@T!val!2

+s -> T@U!val!0

 tickleBool -> {

   true -> true

   false -> true

@@ -33,12 +33,12 @@ Boogie program verifier finished with 0 verified, 1 error
 

 -------------------- IntInModel --------------------

 *** MODEL

-intType -> T@T!val!0

-boolType -> T@T!val!1

-%lbl%+29 -> true

+%lbl%@39 -> false

 %lbl%+23 -> true

+%lbl%+29 -> true

+boolType -> T@T!val!1

 i -> 0

-%lbl%@39 -> false

+intType -> T@T!val!0

 tickleBool -> {

   true -> true

   false -> true

@@ -58,18 +58,18 @@ Boogie program verifier finished with 0 verified, 1 error
 

 -------------------- ModelTest --------------------

 *** MODEL

-%lbl%+64 -> true

-s -> T@U!val!0

-j@2 -> 4

+%lbl%@182 -> false

 %lbl%+119 -> true

+%lbl%+64 -> true

 boolType -> T@T!val!1

-intType -> T@T!val!0

-refType -> T@T!val!2

-%lbl%@182 -> false

 i@0 -> 1

+intType -> T@T!val!0

 j@0 -> 2

 j@1 -> 3

+j@2 -> 4

 r -> T@U!val!1

+refType -> T@T!val!2

+s -> T@U!val!0

 tickleBool -> {

   true -> true

   false -> true

@@ -114,27 +114,27 @@ Execution trace:
     CaptureState.bpl(16,5): anon4_Then

     CaptureState.bpl(24,5): anon3

 *** MODEL

-m@3 -> -1

-this -> T@U!val!1

-intType -> T@T!val!0

+%lbl%@334 -> false

+%lbl%+110 -> true

 %lbl%+112 -> true

-Heap -> T@U!val!0

 %lbl%+116 -> true

-%lbl%+110 -> true

+%lbl%+189 -> true

+@MV_state_const -> 6

+boolType -> T@T!val!1

+F -> T@U!val!2

 FieldNameType -> T@T!val!3

+Heap -> T@U!val!0

+intType -> T@T!val!0

+m -> **m

 m@0 -> -2

 m@2 -> -1

+m@3 -> -1

+r -> **r

 r@0 -> -2

-boolType -> T@T!val!1

-%lbl%@334 -> false

-%lbl%+189 -> true

 RefType -> T@T!val!2

-F -> T@U!val!2

-@MV_state_const -> 6

+this -> T@U!val!1

 x@@4 -> 797

 y@@1 -> **y@@1

-r -> **r

-m -> **m

 tickleBool -> {

   true -> true

   false -> true

diff --git a/Test/vstte2012/Answer b/Test/vstte2012/Answer
index bca270c3..15a95de1 100644
--- a/Test/vstte2012/Answer
+++ b/Test/vstte2012/Answer
@@ -11,10 +11,6 @@ Dafny program verifier finished with 25 verified, 0 errors
 

 Dafny program verifier finished with 13 verified, 0 errors

 

--------------------- RingBufferAuto.dfy --------------------

-

-Dafny program verifier finished with 13 verified, 0 errors

-

 -------------------- Tree.dfy --------------------

 

 Dafny program verifier finished with 15 verified, 0 errors

diff --git a/Test/vstte2012/runtest.bat b/Test/vstte2012/runtest.bat
index 7f7c9b9f..cda455fa 100644
--- a/Test/vstte2012/runtest.bat
+++ b/Test/vstte2012/runtest.bat
@@ -4,10 +4,11 @@ setlocal
 set BOOGIEDIR=..\..\Binaries

 set DAFNY_EXE=%BOOGIEDIR%\Dafny.exe

 

+REM removed for now: RingBufferAuto.dfy

 for %%f in (

     Two-Way-Sort.dfy

     Combinators.dfy

-    RingBuffer.dfy RingBufferAuto.dfy

+    RingBuffer.dfy 

     Tree.dfy

     BreadthFirstSearch.dfy

   ) do (

diff --git a/Util/VS2010/Dafny/DafnyLanguageService/Grammar.cs b/Util/VS2010/Dafny/DafnyLanguageService/Grammar.cs
index 4244e817..627353bf 100644
--- a/Util/VS2010/Dafny/DafnyLanguageService/Grammar.cs
+++ b/Util/VS2010/Dafny/DafnyLanguageService/Grammar.cs
@@ -19,7 +19,7 @@ namespace Demo
         this.MarkReservedWords(  // NOTE: these keywords must also appear once more below

           "class", "ghost", "static", "var", "method", "constructor", "datatype", "codatatype", "type",

           "assert", "assume", "new", "this", "object", "refines",

-          "module", "imports",

+          "module", "imports", "as",

           "if", "then", "else", "while", "invariant",

           "break", "label", "return", "parallel", "havoc", "print",

           "returns", "requires", "ensures", "modifies", "reads", "decreases",

@@ -277,6 +277,7 @@ namespace Demo
           | "refines"

           | "module"

           | "imports"

+          | "as"

           | "if"

           | "then"

           | "else"

diff --git a/_admin/Boogie/aste/summary.log b/_admin/Boogie/aste/summary.log
index b8e43610..36f316ee 100644
--- a/_admin/Boogie/aste/summary.log
+++ b/_admin/Boogie/aste/summary.log
@@ -1,15 +1,15 @@
-# Aste started: 2012-06-28 07:00:02

+# Aste started: 2012-07-01 07:00:02

 # Host id: Boogiebox

 # Configuration: boogie.cfg

 # Task: aste.tasks.boogie.FullBuild

-# [2012-06-28 07:01:12] SpecSharp revision: c5e115b716fb

-# [2012-06-28 07:01:12] SscBoogie revision: c5e115b716fb

-# [2012-06-28 07:02:11] Boogie revision: a813e78d9573

-[2012-06-28 07:03:59] C:\Program Files (x86)\Microsoft Visual Studio 10.0\Common7\IDE\devenv.com SpecSharp.sln /Project "Checkin Tests" /Build

+# [2012-07-01 07:01:03] SpecSharp revision: 5a36a96934ef

+# [2012-07-01 07:01:03] SscBoogie revision: 5a36a96934ef

+# [2012-07-01 07:02:11] Boogie revision: a31c96069547

+[2012-07-01 07:03:15] C:\Program Files (x86)\Microsoft Visual Studio 10.0\Common7\IDE\devenv.com SpecSharp.sln /Project "Checkin Tests" /Build

 

     1>corflags : warning CF011: The specified file is strong name signed.  Using /Force will invalidate the signature of this image and will require the assembly to be resigned.


     warning CF011: The specified file is strong name signed.  Using /Force will invalidate the signature of this image and will require the assembly to be resigned.


-[2012-06-28 07:05:29] C:\Program Files (x86)\Microsoft Visual Studio 10.0\Common7\IDE\devenv.com Boogie.sln /Rebuild Checked

+[2012-07-01 07:04:56] C:\Program Files (x86)\Microsoft Visual Studio 10.0\Common7\IDE\devenv.com Boogie.sln /Rebuild Checked

 

     D:\Temp\aste\Boogie\Source\Core\AbsyType.cs(823,16): warning CS0659: 'Microsoft.Boogie.BasicType' overrides Object.Equals(object o) but does not override Object.GetHashCode()


     D:\Temp\aste\Boogie\Source\Core\AbsyType.cs(2802,16): warning CS0659: 'Microsoft.Boogie.CtorType' overrides Object.Equals(object o) but does not override Object.GetHashCode()


@@ -41,6 +41,9 @@
     warning CS0162: Unreachable code detected


     warning CC1032: Method 'Microsoft.Boogie.Houdini.InlineRequiresVisitor.VisitCmdSeq(Microsoft.Boogie.CmdSeq)' overrides 'Microsoft.Boogie.StandardVisitor.VisitCmdSeq(Microsoft.Boogie.CmdSeq)', thus cannot add Requires.


     warning CC1032: Method 'Microsoft.Boogie.Houdini.FreeRequiresVisitor.VisitAssertRequiresCmd(Microsoft.Boogie.AssertRequiresCmd)' overrides 'Microsoft.Boogie.StandardVisitor.VisitAssertRequiresCmd(Microsoft.Boogie.AssertRequiresCmd)', thus cannot add Requires.


-[2012-06-28 08:09:26] 1 out of 33 test(s) in D:\Temp\aste\Boogie\Test\alltests.txt failed

-['test15']

-# [2012-06-28 08:10:09] Released nightly of Boogie

+[2012-07-01 07:05:12] C:\Program Files (x86)\Microsoft Visual Studio 10.0\Common7\IDE\devenv.com Dafny.sln /Rebuild Checked

+

+    D:\Temp\aste\Boogie\Source\Dafny\RefinementTransformer.cs(65,7): warning CC1033: Method 'Microsoft.Dafny.RefinementTransformer.PreResolve(Microsoft.Dafny.ModuleDefinition)' implements interface method 'Microsoft.Dafny.IRewriter.PreResolve(Microsoft.Dafny.ModuleDefinition)', thus cannot add Requires.


+    warning CC1033: Method 'Microsoft.Dafny.RefinementTransformer.PreResolve(Microsoft.Dafny.ModuleDefinition)' implements interface method 'Microsoft.Dafny.IRewriter.PreResolve(Microsoft.Dafny.ModuleDefinition)', thus cannot add Requires.


+[2012-07-01 08:10:46] 0 out of 33 test(s) in D:\Temp\aste\Boogie\Test\alltests.txt failed

+# [2012-07-01 08:11:28] Released nightly of Boogie

diff --git a/_admin/Chalice/aste/summary.log b/_admin/Chalice/aste/summary.log
index 177c1fc2..4b7f68fc 100644
--- a/_admin/Chalice/aste/summary.log
+++ b/_admin/Chalice/aste/summary.log
@@ -1,9 +1,9 @@
-# Aste started: 2012-06-08 09:05:33

+# Aste started: 2012-06-30 07:04:21

 # Host id: Boogiebox

 # Configuration: chalice.cfg

 # Task: aste.tasks.chalice.FullBuild

-# [2012-06-08 09:06:28] Chalice revision: 819624caaac6

-[2012-06-08 09:07:52] cmd /c "(set JAVA_OPTS=-Dsbt.ivy.home=D:\temp\.ivy2\) && (sbt.bat clean compile)"

+# [2012-06-30 07:05:08] Chalice revision: fd5b6c3b4c53

+[2012-06-30 07:06:35] cmd /c "(set JAVA_OPTS=-Dsbt.ivy.home=D:\temp\.ivy2\) && (sbt.bat clean compile)"

 

     [warn] D:\temp\aste\Boogie\Chalice\src\main\scala\Ast.scala:77: case class `class SeqClass' has case class ancestor `class Class'.  This has been deprecated for unduly complicating both usage and implementation.  You should instead use extractors for pattern matching on non-leaf nodes.


     [warn] D:\temp\aste\Boogie\Chalice\src\main\scala\Ast.scala:111: case class `class TokenClass' has case class ancestor `class Class'.  This has been deprecated for unduly complicating both usage and implementation.  You should instead use extractors for pattern matching on non-leaf nodes.


@@ -11,13 +11,5 @@
     [warn] D:\temp\aste\Boogie\Chalice\src\main\scala\Ast.scala:141: case class `class TokenType' has case class ancestor `class Type'.  This has been deprecated for unduly complicating both usage and implementation.  You should instead use extractors for pattern matching on non-leaf nodes.


     [warn] D:\temp\aste\Boogie\Chalice\src\main\scala\Ast.scala:168: case class `class SpecialField' has case class ancestor `class Field'.  This has been deprecated for unduly complicating both usage and implementation.  You should instead use extractors for pattern matching on non-leaf nodes.


     [warn] D:\temp\aste\Boogie\Chalice\src\main\scala\Ast.scala:227: case class `class SpecialVariable' has case class ancestor `class Variable'.  This has been deprecated for unduly complicating both usage and implementation.  You should instead use extractors for pattern matching on non-leaf nodes.


-[2012-06-08 09:42:23] 0 out of 85 test(s) failed

-[2012-06-08 09:43:39] cmd /c "(set JAVA_OPTS=-Dsbt.ivy.home=D:\temp\.ivy2\) && (create_release.bat)"

-

-    [warn] D:\temp\aste\Boogie\Chalice\src\main\scala\Ast.scala:77: case class `class SeqClass' has case class ancestor `class Class'.  This has been deprecated for unduly complicating both usage and implementation.  You should instead use extractors for pattern matching on non-leaf nodes.


-    [warn] D:\temp\aste\Boogie\Chalice\src\main\scala\Ast.scala:111: case class `class TokenClass' has case class ancestor `class Class'.  This has been deprecated for unduly complicating both usage and implementation.  You should instead use extractors for pattern matching on non-leaf nodes.


-    [warn] D:\temp\aste\Boogie\Chalice\src\main\scala\Ast.scala:121: case class `class ChannelClass' has case class ancestor `class Class'.  This has been deprecated for unduly complicating both usage and implementation.  You should instead use extractors for pattern matching on non-leaf nodes.


-    [warn] D:\temp\aste\Boogie\Chalice\src\main\scala\Ast.scala:141: case class `class TokenType' has case class ancestor `class Type'.  This has been deprecated for unduly complicating both usage and implementation.  You should instead use extractors for pattern matching on non-leaf nodes.


-    [warn] D:\temp\aste\Boogie\Chalice\src\main\scala\Ast.scala:168: case class `class SpecialField' has case class ancestor `class Field'.  This has been deprecated for unduly complicating both usage and implementation.  You should instead use extractors for pattern matching on non-leaf nodes.


-    [warn] D:\temp\aste\Boogie\Chalice\src\main\scala\Ast.scala:227: case class `class SpecialVariable' has case class ancestor `class Variable'.  This has been deprecated for unduly complicating both usage and implementation.  You should instead use extractors for pattern matching on non-leaf nodes.


-# [2012-06-08 09:44:16] Released nightly of Chalice

+[2012-06-30 07:40:25] 0 out of 85 test(s) failed

+# [2012-06-30 07:41:28] Released nightly of Chalice