1 files changed, 51 insertions, 51 deletions

diff --git a/src/unify.cpp b/src/unify.cpp
index 52a3265..a7f7822 100644
--- a/src/unify.cpp
+++ b/src/unify.cpp
@@ -26,29 +26,25 @@
  * with a specific set of argument types
  */
 Subst
-TEnv::buildSubst(const AType* genericT, const AType& argsT)
+TEnv::buildSubst(const AST* genericT, const AST& argsT)
 {
 	Subst subst;
 
 	// Build substitution to apply to generic type
-	const ATuple* genericProtT = genericT->list_ref(1)->as_tuple();
+	const ATuple* genericProtT = genericT->as_tuple()->list_ref(1)->as_tuple();
 	ATuple::const_iterator g = genericProtT->begin();
-	ATuple::const_iterator a = argsT.begin();
-	for (; a != argsT.end(); ++a, ++g) {
-		const AType* genericArgT = (*g)->to_type();
-		const AType* callArgT    = (*a)->to_type();
-		if (callArgT->kind == AType::EXPR) {
-			assert(genericArgT->kind == AType::EXPR);
-			ATuple::const_iterator gi = genericArgT->begin();
-			ATuple::const_iterator ci = callArgT->begin();
-			for (; gi != genericArgT->end(); ++gi, ++ci) {
-				const AType* gT = (*gi)->to_type();
-				const AType* aT = (*ci)->to_type();
-				if (gT && aT)
-					subst.add(gT, aT);
+	ATuple::const_iterator a = argsT.as_tuple()->begin();
+	for (; a != argsT.as_tuple()->end(); ++a, ++g) {
+		if (AType::is_expr(*a)) {
+			assert(AType::is_expr(*g));
+			ATuple::const_iterator gi = (*g)->as_tuple()->begin();
+			ATuple::const_iterator ci = (*a)->as_tuple()->begin();
+			for (; gi != (*g)->as_tuple()->end(); ++gi, ++ci) {
+				if ((*gi) && (*ci))
+					subst.add(*gi, *ci);
 			}
 		} else {
-			subst.add(genericArgT, callArgT);
+			subst.add(*g, *a);
 		}
 	}
 
@@ -56,29 +52,34 @@ TEnv::buildSubst(const AType* genericT, const AType& argsT)
 }
 
 void
-Constraints::constrain(TEnv& tenv, const AST* o, const AType* t)
+Constraints::constrain(TEnv& tenv, const AST* o, const AST* t)
 {
 	assert(o);
 	assert(t);
 	push_back(Constraint(tenv.var(o), t));
 }
 
-static const AType*
-substitute(const AType* tup, const AType* from, const AType* to)
+static const AST*
+substitute(const AST* in, const AST* from, const AST* to)
 {
-	if (!tup) return NULL;
-	TList ret;
-	FOREACHP(AType::const_iterator, i, tup) {
+	if (in == from)
+		return to;
+
+	const ATuple* tup = in->to_tuple();
+	if (!tup)
+		return from;
+	
+	List ret;
+	FOREACHP(ATuple::const_iterator, i, tup->as_tuple()) {
 		if (**i == *from) {
-			ret.push_back(new AType(*to, (*i)->loc));
+			ret.push_back(to); // FIXME: should be a copy w/ (*i)->loc
 		} else if (*i != to) {
-			const AType* elem = (*i)->as_type();
-			if (elem->kind == AType::EXPR)
-				ret.push_back(substitute(elem, from, to));
+			if (AType::is_expr(*i))
+				ret.push_back(substitute(*i, from, to));
 			else
-				ret.push_back(elem);
+				ret.push_back(*i);
 		} else {
-			ret.push_back((*i)->as_type());
+			ret.push_back(*i);
 		}
 	}
 	return ret.head;
@@ -102,17 +103,17 @@ Subst::compose(const Subst& delta, const Subst& gamma)
 
 /// Replace all occurrences of @a s with @a t
 Constraints&
-Constraints::replace(const AType* s, const AType* t)
+Constraints::replace(const AST* s, const AST* t)
 {
 	for (Constraints::iterator c = begin(); c != end(); ++c) {
 		if (*c->first == *s) {
-			c->first = new AType(*t, c->first->loc);
-		} else if (c->first->kind == AType::EXPR) {
+			c->first = t; // FIXME: should be copy w/ c->first->loc;
+		} else if (AType::is_expr(c->first)) {
 			c->first = substitute(c->first, s, t);
 		}
 		if (*c->second == *s) {
-			c->second = new AType(*t, c->second->loc);
-		} else if (c->second->kind == AType::EXPR) {
+			c->second = t; // FIXME: should be copy w/ c->second->loc;
+		} else if (AType::is_expr(c->second)) {
 			c->second = substitute(c->second, s, t);
 		}
 	}
@@ -120,10 +121,9 @@ Constraints::replace(const AType* s, const AType* t)
 }
 
 static inline bool
-is_dots(const AST* ast)
+is_dots(const AST* type)
 {
-	const AType* type = ast->as_type();
-	return (type->kind == AType::NAME && type->head()->str() == "...");
+	return (AType::is_name(type) && type->as_symbol()->str() == "...");
 }
 
 /// Unify a type constraint set (TAPL 22.4)
@@ -134,30 +134,30 @@ unify(const Constraints& constraints)
 		return Subst();
 
 	Constraints::const_iterator i  = constraints.begin();
-	const AType*                s  = i->first;
-	const AType*                t  = i->second;
+	const AST*                  s  = i->first;
+	const AST*                  t  = i->second;
 	Constraints                 cp(++i, constraints.end());
 
 	if (*s == *t) {
 		return unify(cp);
-	} else if (s->kind == AType::VAR && !list_contains(t, s)) {
+	} else if (AType::is_var(s) && !list_contains(t->to_tuple(), s)) {
 		return Subst::compose(unify(cp.replace(s, t)), Subst(s, t));
-	} else if (t->kind == AType::VAR && !list_contains(s, t)) {
+	} else if (AType::is_var(t) && !list_contains(s->to_tuple(), t)) {
 		return Subst::compose(unify(cp.replace(t, s)), Subst(t, s));
-	} else if (s->kind == AType::EXPR && t->kind == AType::EXPR) {
-		AType::const_iterator si = s->begin();
-		AType::const_iterator ti = t->begin();
-		for (; si != s->end() && ti != t->end(); ++si, ++ti) {
-			const AType* st = (*si)->as_type();
-			const AType* tt = (*ti)->as_type();
-			if (is_dots(st) || is_dots(tt))
+	} else if (AType::is_expr(s) && AType::is_expr(t)) {
+		const ATuple* const st = s->as_tuple();
+		const ATuple* const tt = t->as_tuple();
+		ATuple::const_iterator si = st->begin();
+		ATuple::const_iterator ti = tt->begin();
+		for (; si != st->end() && ti != tt->end(); ++si, ++ti) {
+			if (is_dots(*si) || is_dots(*ti))
 				return unify(cp);
 			else
-				cp.push_back(Constraint(st, tt));
+				cp.push_back(Constraint(*si, *ti));
 		}
-		if ((si == s->end() && ti == t->end())
-		    || (si != s->end() && is_dots(*si))
-		    || (ti != t->end() && is_dots(*ti)))
+		if ((si == st->end() && ti == tt->end())
+		    || (si != st->end() && is_dots(*si))
+		    || (ti != tt->end() && is_dots(*ti)))
 			return unify(cp);
 	}
 	throw Error(s->loc,