1 files changed, 34 insertions, 0 deletions
diff --git a/Source/Forro/Ast.fs b/Source/Forro/Ast.fs
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index 00000000..fa4db8ec
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+namespace Forro
+
+type Field = Head | Tail | Valid
+
+type Variable = Var of string
+
+type Operator = Eq | Neq | Plus | Minus | Times | Less | AtMost | And | Or
+
+type Expression =
+    | Constant of int
+    | Null
+    | Identifier of Variable
+    | Not of Expression
+    | Binary of Operator * Expression * Expression
+    | Select of Expression * Field
+    | Old of Expression
+
+type StmtList  =
+    Block of Statement list
+
+and Statement =
+    | Assign of Variable * Expression
+    | Update of Expression * Field * Expression
+    | Alloc of Variable * Expression * Expression
+    | IfStmt of Expression * StmtList * StmtList
+    | WhileStmt of Expression * Expression list * StmtList
+    | CallStmt of Variable list * string * Expression list
+    | Assert of Expression
+
+type Procedure =
+    Proc of string * Variable list * Variable list * Expression * Expression * StmtList
+
+type Program =
+    Prog of Procedure list