BIND

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

diff --git a/src/env.sml b/src/env.sml
index acc7e36..91fb69d 100644 (file)
--- a/src/env.sml
+++ b/src/env.sml
@@ -70,6 +70,10 @@ fun mapFail f [] = SOME []
 fun list f (EList ls, _) = mapFail f ls
   | list _ _ = NONE
 
+fun none func f (_, []) = (f ();
+                          SM.empty)
+  | none func _ (_, es) = badArgs (func, es)
+
 fun one func (name, arg) f (_, [e]) =
     (case arg e of
         NONE => badArg (func, name, e)
@@ -85,32 +89,60 @@ fun two func (name1, arg1, name2, arg2) f (_, [e1, e2]) =
                                SM.empty))
   | two func _ _ (_, es) = badArgs (func, es)
 
+
+fun oneV func (name, arg) f (evs, [e]) =
+    (case arg e of
+        NONE => badArg (func, name, e)
+       | SOME v => (f (evs, v);
+                   SM.empty))
+  | oneV func _ _ (_, es) = badArgs (func, es)
+
+
+fun env arg (evs, name) =
+    case SM.find (evs, name) of
+       NONE => raise Fail ("Unavailable environment variable " ^ name)
+      | SOME e =>
+       case arg e of
+           NONE => raise Fail ("Bad format for environment variable " ^ name)
+         | SOME v => v
+
 fun type_one func arg f =
     registerType (func, fn e =>
                           case arg e of
                               NONE => false
                             | SOME v => f v)
 
+fun action_none name f = registerAction (name, none name f)
 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 actionV_one name args f = registerAction (name, oneV name args f)
+
+fun container_none name (f, g) = registerContainer (name, none name f, g)
 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"),
-                  SM.empty)
+fun containerV_one name args (f, g) = registerContainer (name, oneV name args f, g)
 
-fun lookupType (ts, _) name = SS.member (ts, name)
-fun lookupVal (_, vs) name =
+type env = SS.set * (typ * exp option) SM.map * SS.set
+val empty : env = (SS.empty, SM.empty, SS.empty)
+
+fun lookupType (ts, _, _) name = SS.member (ts, name)
+fun lookupVal (_, vs, _) name =
     case SM.find (vs, name) of
        NONE => NONE
       | SOME (t, _) => SOME t
-fun lookupEquation (_, vs) name =
+fun lookupEquation (_, vs, _) name =
     case SM.find (vs, name) of
        NONE => NONE
       | SOME (_, eqo) => eqo
+fun lookupContext (_, _, cs) name = SS.member (cs, name)
+
+fun bindType (ts, vs, cs) name = (SS.add (ts, name), vs, cs)
+fun bindVal (ts, vs, cs) (name, t, eqo) = (ts, SM.insert (vs, name, (t, eqo)), cs)
+fun bindContext (ts, vs, cs) name = (ts, vs, SS.add (cs, name))
 
-fun bindType (ts, vs) name = (SS.add (ts, name), vs)
-fun bindVal (ts, vs) (name, t, eqo) = (ts, SM.insert (vs, name, (t, eqo)))
+fun types (ts, _, _) = ts
+fun vals (_, vs, _) = SM.foldli (fn (name, _, vs) => SS.add (vs, name)) SS.empty vs
+fun contexts (_, _, cs) = cs
 
 end