Factor error message generation into a separate file; add '-tc' flag to domtool-client

[hcoop/domtool2.git] / src / ast.sml

diff --git a/src/ast.sml b/src/ast.sml
index 667a26c..0e8688d 100644 (file)
--- a/src/ast.sml
+++ b/src/ast.sml
@@ -59,7 +59,7 @@ datatype typ' =
        | TUnif of string * typ option ref
        (* Unification variable to be determined during type-checking *)
 withtype typ = typ' * position
-     and record = typ StringMap.map
+     and record = (typ' * position) StringMap.map
 
 datatype exp' =
         EInt of int
@@ -89,6 +89,8 @@ datatype exp' =
        * action are abandoned *)
        | EWith of exp * exp
        (* Apply a TNested to an action *)
+       | EALam of string * pred * exp
+       (* Abstraction for building TNested values *)
 withtype exp = exp' * position
 
 datatype decl' =
@@ -103,4 +105,17 @@ type file = string option * decl list * exp option
 fun multiApp (f, loc, args) =
     foldl (fn (arg, e) => (EApp (e, arg), loc)) f args
 
+datatype unification_error =
+        UnifyPred of pred * pred
+       | UnifyTyp of typ * typ
+       | UnifyOccurs of string * typ
+
+exception Unify of unification_error
+
+datatype type_error =
+        WrongType of string * exp * typ * typ * unification_error option
+       | WrongForm of string * string * exp * typ * unification_error option
+       | UnboundVariable of string
+       | WrongPred of string * pred * pred
+
 end