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 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)
+fun containerV_one name args (f, g) = registerContainer (name, oneV name args f, g)
+
type env = SS.set * (typ * exp option) SM.map * SS.set
val empty : env = (SS.empty, SM.empty, SS.empty)