containers := SM.insert (!containers, name, (befor, after))
fun container name = SM.find (!containers, name)
+local
+ val pr = ref (fn () => ())
+in
+
+fun registerPre f =
+ let
+ val old = !pr
+ in
+ pr := (fn () => (old (); f ()))
+ end
+fun pre () = !pr ()
+
+end
+
+local
+ val pst = ref (fn () => ())
+in
+
+fun registerPost f =
+ let
+ val old = !pst
+ in
+ pst := (fn () => (old (); f ()))
+ end
+fun post () = !pst ()
+
+end
+
fun badArgs (name, args) =
(print ("Invalid arguments to " ^ name ^ "\n");
app (fn arg => Print.preface ("Argument: ", Print.p_exp arg)) args;
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)
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 twoV func (name1, arg1, name2, arg2) f (evs, [e1, e2]) =
+ (case (arg1 e1, arg2 e2) of
+ (NONE, _) => badArg (func, name1, e1)
+ | (_, NONE) => badArg (func, name2, e2)
+ | (SOME v1, SOME v2) => (f (evs, v1, v2);
+ SM.empty))
+ | twoV 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_none name f = registerAction (name, fn (env, _) => (f env; env))
+fun actionV_one name args f = registerAction (name, oneV name args f)
+fun actionV_two name args f = registerAction (name, twoV 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