Dafny: Removed the previous optional curly braces in match expressions (use parens instead, when needed!).

4 files changed, 83 insertions, 112 deletions

diff --git a/Source/Dafny/Dafny.atg b/Source/Dafny/Dafny.atg
index 8c771dd7..3d07af57 100644
--- a/Source/Dafny/Dafny.atg
+++ b/Source/Dafny/Dafny.atg
@@ -485,22 +485,14 @@ FunctionBody<out Expression! e>
   .

   

 MatchExpression<out Expression! e>

-= (. Token! x;

+= (. Token! x;  MatchCaseExpr! c;

      List<MatchCaseExpr!> cases = new List<MatchCaseExpr!>();

   .)

   "match"                     (. x = token; .)

   Expression<out e>

-  ( "{" CaseExpressions<cases> "}"  /* curly braces are optional; in the future, when match expressions can be nested, this will be handy */

-  /* Note, because the curly braces are optional, Coco generates a "CaseExpressions deletable" warning, but that's okay. */

-  | CaseExpressions<cases>

-  )

-  (. e = new MatchExpr(x, e, cases); .)

-  .

-

-CaseExpressions<List<MatchCaseExpr!\>! cases>

-= (. MatchCaseExpr! c; .)

   { CaseExpression<out c>     (. cases.Add(c); .)

   }

+  (. e = new MatchExpr(x, e, cases); .)

   .

 

 CaseExpression<out MatchCaseExpr! c>

@@ -696,18 +688,15 @@ Guard<out Expression e>   /* null represents demonic-choice */
   .

 

 MatchStmt<out Statement! s>

-= (. Token x;  Expression! e;

+= (. Token x;  Expression! e;  MatchCaseStmt! c;

      List<MatchCaseStmt!> cases = new List<MatchCaseStmt!>(); .)

   "match"                     (. x = token; .)

   Expression<out e>

-  "{" CaseStatements<cases> "}"

-  (. s = new MatchStmt(x, e, cases); .)

-  .

-

-CaseStatements<List<MatchCaseStmt!\>! cases>

-= (. MatchCaseStmt! c; .)

+  "{"

   { CaseStatement<out c>     (. cases.Add(c); .)

   }

+  "}"

+  (. s = new MatchStmt(x, e, cases); .)

   .

 

 CaseStatement<out MatchCaseStmt! c>

diff --git a/Source/Dafny/Parser.ssc b/Source/Dafny/Parser.ssc
index 4761d317..9551f031 100644
--- a/Source/Dafny/Parser.ssc
+++ b/Source/Dafny/Parser.ssc
@@ -721,28 +721,17 @@ List<Expression!>! decreases) {
 	}

 

 	static void MatchExpression(out Expression! e) {

-		Token! x;

+		Token! x;  MatchCaseExpr! c;

 		List<MatchCaseExpr!> cases = new List<MatchCaseExpr!>();

 		

 		Expect(36);

 		x = token; 

 		Expression(out e);

-		if (t.kind == 6) {

-			Get();

-			CaseExpressions(cases);

-			Expect(7);

-		} else if (t.kind == 7 || t.kind == 37) {

-			CaseExpressions(cases);

-		} else Error(108);

-		e = new MatchExpr(x, e, cases); 

-	}

-

-	static void CaseExpressions(List<MatchCaseExpr!>! cases) {

-		MatchCaseExpr! c; 

 		while (t.kind == 37) {

 			CaseExpression(out c);

 			cases.Add(c); 

 		}

+		e = new MatchExpr(x, e, cases); 

 	}

 

 	static void CaseExpression(out MatchCaseExpr! c) {

@@ -783,7 +772,7 @@ List<Expression!>! decreases) {
 			ss.Add(s); 

 		} else if (t.kind == 9 || t.kind == 14) {

 			VarDeclStmts(ss);

-		} else Error(109);

+		} else Error(108);

 	}

 

 	static void OneStmt(out Statement! s) {

@@ -857,7 +846,7 @@ List<Expression!>! decreases) {
 			s = new ReturnStmt(x); 

 			break;

 		}

-		default: Error(110); break;

+		default: Error(109); break;

 		}

 	}

 

@@ -1009,7 +998,7 @@ List<Expression!>! decreases) {
 			} else if (t.kind == 6) {

 				BlockStmt(out s);

 				els = s; 

-			} else Error(111);

+			} else Error(110);

 		}

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

 	}

@@ -1048,13 +1037,16 @@ List<Expression!>! decreases) {
 	}

 

 	static void MatchStmt(out Statement! s) {

-		Token x;  Expression! e;

+		Token x;  Expression! e;  MatchCaseStmt! c;

 		List<MatchCaseStmt!> cases = new List<MatchCaseStmt!>(); 

 		Expect(36);

 		x = token; 

 		Expression(out e);

 		Expect(6);

-		CaseStatements(cases);

+		while (t.kind == 37) {

+			CaseStatement(out c);

+			cases.Add(c); 

+		}

 		Expect(7);

 		s = new MatchStmt(x, e, cases); 

 	}

@@ -1106,7 +1098,7 @@ List<Expression!>! decreases) {
 		} else if (t.kind == 44) {

 			HavocStmt(out s);

 			if (s is AssignStmt) { bodyAssign = (AssignStmt)s; } 

-		} else Error(112);

+		} else Error(111);

 		Expect(7);

 		if (bodyAssign != null) {

 		 s = new ForeachStmt(x, new BoundVar(boundVar, boundVar.val, ty), collection, range, bodyPrefix, bodyAssign);

@@ -1132,7 +1124,7 @@ List<Expression!>! decreases) {
 		} else if (StartOf(7)) {

 			Expression(out ee);

 			e = ee; 

-		} else Error(113);

+		} else Error(112);

 		if (e == null && ty == null) { e = dummyExpr; } 

 	}

 

@@ -1142,7 +1134,7 @@ List<Expression!>! decreases) {
 			IdentOrFuncExpression(out e);

 		} else if (t.kind == 26 || t.kind == 88 || t.kind == 89) {

 			ObjectExpression(out e);

-		} else Error(114);

+		} else Error(113);

 		while (t.kind == 83 || t.kind == 85) {

 			SelectOrCallSuffix(ref e);

 		}

@@ -1184,18 +1176,10 @@ List<Expression!>! decreases) {
 		} else if (StartOf(7)) {

 			Expression(out ee);

 			e = ee; 

-		} else Error(115);

+		} else Error(114);

 		Expect(27);

 	}

 

-	static void CaseStatements(List<MatchCaseStmt!>! cases) {

-		MatchCaseStmt! c; 

-		while (t.kind == 37) {

-			CaseStatement(out c);

-			cases.Add(c); 

-		}

-	}

-

 	static void CaseStatement(out MatchCaseStmt! c) {

 		Token! x, id, arg;

 		List<BoundVar!> arguments = new List<BoundVar!>();

@@ -1234,7 +1218,7 @@ List<Expression!>! decreases) {
 		} else if (t.kind == 26 || t.kind == 88 || t.kind == 89) {

 			ObjectExpression(out e);

 			SelectOrCallSuffix(ref e);

-		} else Error(116);

+		} else Error(115);

 		while (t.kind == 83 || t.kind == 85) {

 			SelectOrCallSuffix(ref e);

 		}

@@ -1267,7 +1251,7 @@ List<Expression!>! decreases) {
 			Get();

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

 			Get();

-		} else Error(117);

+		} else Error(116);

 	}

 

 	static void LogicalExpression(out Expression! e0) {

@@ -1305,7 +1289,7 @@ List<Expression!>! decreases) {
 			Get();

 		} else if (t.kind == 59) {

 			Get();

-		} else Error(118);

+		} else Error(117);

 	}

 

 	static void RelationalExpression(out Expression! e0) {

@@ -1323,7 +1307,7 @@ List<Expression!>! decreases) {
 			Get();

 		} else if (t.kind == 61) {

 			Get();

-		} else Error(119);

+		} else Error(118);

 	}

 

 	static void OrOp() {

@@ -1331,7 +1315,7 @@ List<Expression!>! decreases) {
 			Get();

 		} else if (t.kind == 63) {

 			Get();

-		} else Error(120);

+		} else Error(119);

 	}

 

 	static void Term(out Expression! e0) {

@@ -1407,7 +1391,7 @@ List<Expression!>! decreases) {
 			x = token;  op = BinaryExpr.Opcode.Ge; 

 			break;

 		}

-		default: Error(121); break;

+		default: Error(120); break;

 		}

 	}

 

@@ -1429,7 +1413,7 @@ List<Expression!>! decreases) {
 		} else if (t.kind == 74) {

 			Get();

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

-		} else Error(122);

+		} else Error(121);

 	}

 

 	static void UnaryExpression(out Expression! e) {

@@ -1448,7 +1432,7 @@ List<Expression!>! decreases) {
 			SelectExpression(out e);

 		} else if (StartOf(15)) {

 			ConstAtomExpression(out e);

-		} else Error(123);

+		} else Error(122);

 	}

 

 	static void MulOp(out Token! x, out BinaryExpr.Opcode op) {

@@ -1462,7 +1446,7 @@ List<Expression!>! decreases) {
 		} else if (t.kind == 76) {

 			Get();

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

-		} else Error(124);

+		} else Error(123);

 	}

 

 	static void NegOp() {

@@ -1470,7 +1454,7 @@ List<Expression!>! decreases) {
 			Get();

 		} else if (t.kind == 78) {

 			Get();

-		} else Error(125);

+		} else Error(124);

 	}

 

 	static void ConstAtomExpression(out Expression! e) {

@@ -1552,7 +1536,7 @@ List<Expression!>! decreases) {
 			Expect(86);

 			break;

 		}

-		default: Error(126); break;

+		default: Error(125); break;

 		}

 	}

 

@@ -1607,9 +1591,9 @@ List<Expression!>! decreases) {
 				QuantifierGuts(out e);

 			} else if (StartOf(7)) {

 				Expression(out e);

-			} else Error(127);

+			} else Error(126);

 			Expect(27);

-		} else Error(128);

+		} else Error(127);

 	}

 

 	static void SelectOrCallSuffix(ref Expression! e) {

@@ -1654,7 +1638,7 @@ List<Expression!>! decreases) {
 				Get();

 				Expression(out ee);

 				anyDots = true;  e1 = ee; 

-			} else Error(129);

+			} else Error(128);

 			assert !anyDots ==> e0 != null;

 			if (anyDots) {

 			  assert e0 != null || e1 != null;

@@ -1668,7 +1652,7 @@ List<Expression!>! decreases) {
 			}

 			

 			Expect(86);

-		} else Error(130);

+		} else Error(129);

 	}

 

 	static void QuantifierGuts(out Expression! q) {

@@ -1687,7 +1671,7 @@ List<Expression!>! decreases) {
 		} else if (t.kind == 92 || t.kind == 93) {

 			Exists();

 			x = token; 

-		} else Error(131);

+		} else Error(130);

 		parseVarScope.PushMarker(); 

 		IdentTypeOptional(out bv);

 		bvars.Add(bv);  parseVarScope.Push(bv.Name, bv.Name); 

@@ -1715,7 +1699,7 @@ List<Expression!>! decreases) {
 			Get();

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

 			Get();

-		} else Error(132);

+		} else Error(131);

 	}

 

 	static void Exists() {

@@ -1723,7 +1707,7 @@ List<Expression!>! decreases) {
 			Get();

 		} else if (t.kind == 93) {

 			Get();

-		} else Error(133);

+		} else Error(132);

 	}

 

 	static void AttributeOrTrigger(ref Attributes attrs, ref Triggers trigs) {

@@ -1736,7 +1720,7 @@ List<Expression!>! decreases) {
 			es = new List<Expression!>(); 

 			Expressions(es);

 			trigs = new Triggers(es, trigs); 

-		} else Error(134);

+		} else Error(133);

 		Expect(7);

 	}

 

@@ -1745,7 +1729,7 @@ List<Expression!>! decreases) {
 			Get();

 		} else if (t.kind == 95) {

 			Get();

-		} else Error(135);

+		} else Error(134);

 	}

 

 	static void AttributeBody(ref Attributes attrs) {

@@ -1776,7 +1760,7 @@ List<Expression!>! decreases) {
 		} else if (StartOf(7)) {

 			Expression(out e);

 			arg = new Attributes.Argument(e); 

-		} else Error(136);

+		} else Error(135);

 	}

 

 

@@ -1903,35 +1887,34 @@ List<Expression!>! decreases) {
 			case 105: s = "invalid FunctionSpec"; break;

 			case 106: s = "invalid FunctionBody"; break;

 			case 107: s = "invalid PossiblyWildExpression"; break;

-			case 108: s = "invalid MatchExpression"; break;

-			case 109: s = "invalid Stmt"; break;

-			case 110: s = "invalid OneStmt"; break;

-			case 111: s = "invalid IfStmt"; break;

-			case 112: s = "invalid ForeachStmt"; break;

-			case 113: s = "invalid AssignRhs"; break;

-			case 114: s = "invalid SelectExpression"; break;

-			case 115: s = "invalid Guard"; break;

-			case 116: s = "invalid CallStmtSubExpr"; break;

-			case 117: s = "invalid EquivOp"; break;

-			case 118: s = "invalid ImpliesOp"; break;

-			case 119: s = "invalid AndOp"; break;

-			case 120: s = "invalid OrOp"; break;

-			case 121: s = "invalid RelOp"; break;

-			case 122: s = "invalid AddOp"; break;

-			case 123: s = "invalid UnaryExpression"; break;

-			case 124: s = "invalid MulOp"; break;

-			case 125: s = "invalid NegOp"; break;

-			case 126: s = "invalid ConstAtomExpression"; break;

+			case 108: s = "invalid Stmt"; break;

+			case 109: s = "invalid OneStmt"; break;

+			case 110: s = "invalid IfStmt"; break;

+			case 111: s = "invalid ForeachStmt"; break;

+			case 112: s = "invalid AssignRhs"; break;

+			case 113: s = "invalid SelectExpression"; break;

+			case 114: s = "invalid Guard"; break;

+			case 115: s = "invalid CallStmtSubExpr"; break;

+			case 116: s = "invalid EquivOp"; break;

+			case 117: s = "invalid ImpliesOp"; break;

+			case 118: s = "invalid AndOp"; break;

+			case 119: s = "invalid OrOp"; break;

+			case 120: s = "invalid RelOp"; break;

+			case 121: s = "invalid AddOp"; break;

+			case 122: s = "invalid UnaryExpression"; break;

+			case 123: s = "invalid MulOp"; break;

+			case 124: s = "invalid NegOp"; break;

+			case 125: s = "invalid ConstAtomExpression"; break;

+			case 126: s = "invalid ObjectExpression"; break;

 			case 127: s = "invalid ObjectExpression"; break;

-			case 128: s = "invalid ObjectExpression"; break;

+			case 128: s = "invalid SelectOrCallSuffix"; break;

 			case 129: s = "invalid SelectOrCallSuffix"; break;

-			case 130: s = "invalid SelectOrCallSuffix"; break;

-			case 131: s = "invalid QuantifierGuts"; break;

-			case 132: s = "invalid Forall"; break;

-			case 133: s = "invalid Exists"; break;

-			case 134: s = "invalid AttributeOrTrigger"; break;

-			case 135: s = "invalid QSep"; break;

-			case 136: s = "invalid AttributeArg"; break;

+			case 130: s = "invalid QuantifierGuts"; break;

+			case 131: s = "invalid Forall"; break;

+			case 132: s = "invalid Exists"; break;

+			case 133: s = "invalid AttributeOrTrigger"; break;

+			case 134: s = "invalid QSep"; break;

+			case 135: s = "invalid AttributeArg"; break;

 

 			default: s = "error " + n; break;

 		}

diff --git a/Source/Dafny/Printer.ssc b/Source/Dafny/Printer.ssc
index bf493101..6f3629d6 100644
--- a/Source/Dafny/Printer.ssc
+++ b/Source/Dafny/Printer.ssc
@@ -303,6 +303,13 @@ namespace Microsoft.Dafny {
       wr.Write(ty.ToString());

     }

 

+    public void PrintType(string! prefix, Type! ty) {

+      string s = ty.ToString();

+      if (s != "?") {

+        wr.Write("{0}{1}", prefix, s);

+      }

+    }

+

     // ----------------------------- PrintStatement -----------------------------

     

     /// <summary>

@@ -359,8 +366,7 @@ namespace Microsoft.Dafny {
         }

         wr.Write("var {0}", s.Name);

         if (s.OptionalType != null) {

-          wr.Write(": ");

-          PrintType(s.OptionalType);

+          PrintType(": ", s.OptionalType);

         }

         if (s.Rhs != null) {

           wr.Write(" := ");

@@ -386,7 +392,7 @@ namespace Microsoft.Dafny {
         }

         wr.Write("{0}(", s.MethodName);

         PrintExpressionList(s.Args);

-        wr.Write(")");

+        wr.Write(");");

         

       } else if (stmt is BlockStmt) {

         wr.WriteLine("{");

@@ -526,11 +532,8 @@ namespace Microsoft.Dafny {
         MatchExpr me = (MatchExpr)expr;

         wr.Write("match ");

         PrintExpression(me.Source);

-        bool needsCurlies = exists{MatchCaseExpr mc in me.Cases; mc.Body is MatchExpr};

-        wr.WriteLine(needsCurlies ? " {" : "");

-        int caseInd = indent + (needsCurlies ? IndentAmount : 0);

         foreach (MatchCaseExpr mc in me.Cases) {

-          Indent(caseInd);

+          Indent(indent);

           wr.Write("case {0}", mc.Id);

           if (mc.Arguments.Count != 0) {

             string sep = "(";

@@ -541,11 +544,7 @@ namespace Microsoft.Dafny {
             wr.Write(")");

           }

           wr.WriteLine(" =>");

-          PrintExtendedExpr(mc.Body, caseInd + IndentAmount);

-        }

-        if (needsCurlies) {

-          Indent(indent);

-          wr.WriteLine("}");

+          PrintExtendedExpr(mc.Body, indent + IndentAmount);

         }

       } else {

         PrintExpression(expr, indent);

@@ -781,9 +780,9 @@ namespace Microsoft.Dafny {
         wr.Write(e is ForallExpr ? "(forall " : "(exists ");

         string sep = "";

         foreach (BoundVar bv in e.BoundVars) {

-          wr.Write("{0}{1}: ", sep, bv.Name);

+          wr.Write("{0}{1}", sep, bv.Name);

           sep = ", ";

-          PrintType(bv.Type);

+          PrintType(": ", bv.Type);

         }

         wr.Write(" :: ");

         PrintAttributes(e.Attributes);

diff --git a/Test/dafny0/Answer b/Test/dafny0/Answer
index 8758ec69..0a419802 100644
--- a/Test/dafny0/Answer
+++ b/Test/dafny0/Answer
@@ -22,10 +22,10 @@ class MyClass<T, U> {
       } else {

         this.x := x + 0;

       }

-      call t, u, v := M(true, lotsaObjects)

+      call t, u, v := M(true, lotsaObjects);

       var to: MyClass<T,U>;

-      call to, u, v := M(true, lotsaObjects)

-      call to, u, v := to.M(true, lotsaObjects)

+      call to, u, v := M(true, lotsaObjects);

+      call to, u, v := to.M(true, lotsaObjects);

       assert v[x] != null ==> null !in v[2 .. x][1..][5 := v[this.x]][..10];

     }

   }