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

diff --git a/src/env.sml b/src/env.sml
index 2141f64..acc7e36 100644 (file)
--- a/src/env.sml
+++ b/src/env.sml
@@ -41,7 +41,60 @@ fun registerContainer (name, befor, after) =
     containers := SM.insert (!containers, name, (befor, after))
 fun container name = SM.find (!containers, name)
 
     containers := SM.insert (!containers, name, (befor, after))
 fun container name = SM.find (!containers, name)
 

-fun badArgs name = raise Fail ("Invalid arguments to " ^ name)
+fun badArgs (name, args) =
+    (print ("Invalid arguments to " ^ name ^ "\n");
+     app (fn arg => Print.preface ("Argument: ", Print.p_exp arg)) args;
+     raise Domain)
+fun badArg (func, arg, v) =
+    (print ("Invalid " ^ arg ^ " argument to " ^ func ^ "\n");
+     Print.preface ("Argument: ", Print.p_exp v);
+     raise Domain)
+
+type 'a arg = exp -> 'a option
+
+fun int (EInt n, _) = SOME n
+  | int _ = NONE
+
+fun string (EString s, _) = SOME s
+  | string _ = NONE
+
+fun mapFail f [] = SOME []
+  | mapFail f (h :: t) =
+    case f h of
+       NONE => NONE
+      | SOME h' =>
+       case mapFail f t of
+           NONE => NONE
+         | SOME t' => SOME (h' :: t')
+
+fun list f (EList ls, _) = mapFail f ls
+  | list _ _ = NONE
+
+fun one func (name, arg) f (_, [e]) =
+    (case arg e of
+        NONE => badArg (func, name, e)
+       | SOME v => (f v;
+                   SM.empty))
+  | one func _ _ (_, es) = badArgs (func, es)
+
+fun two func (name1, arg1, name2, arg2) f (_, [e1, e2]) =
+    (case (arg1 e1, arg2 e2) of
+        (NONE, _) => badArg (func, name1, e1)
+       | (_, NONE) => badArg (func, name2, e2)
+       | (SOME v1, SOME v2) => (f (v1, v2);
+                               SM.empty))
+  | two func _ _ (_, es) = badArgs (func, es)
+
+fun type_one func arg f =
+    registerType (func, fn e =>
+                          case arg e of
+                              NONE => false
+                            | SOME v => f v)
+
+fun action_one name args f = registerAction (name, one name args f)
+fun action_two name args f = registerAction (name, two name args f)
+
+fun container_one name args (f, g) = registerContainer (name, one name args f, g)

 
 type env = SS.set * (typ * exp option) SM.map
 val empty : env = (SS.add (SS.singleton "int", "string"),
 
 type env = SS.set * (typ * exp option) SM.map
 val empty : env = (SS.add (SS.singleton "int", "string"),