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Remap type params according to bound scope.

	Getting closer to scoping type params properly. Still
	not fully there.

--- a/lib/std/endian.myr

+++ b/lib/std/endian.myr

@@ -1,6 +1,6 @@

 pkg std =

-	generic hosttonet	: (v : @a -> @a)

-	generic nettohost	: (v : @a -> @a)

+	generic hosttonet	: (v : @a::(integral,numeric) -> @a::(integral,numeric))

+	generic nettohost	: (v : @a::(integral,numeric) -> @a::(integral,numeric))

 ;;

 /* FIXME: we only support little endian platforms right now,

--- a/parse/infer.c

+++ b/parse/infer.c

@@ -32,10 +32,6 @@

 	Stab **postcheckscope;

 	size_t npostcheckscope;

-	/* type params bound at the current point */

-	Htab **tybindings;

-	size_t ntybindings;

-

 	/* generic declarations to be specialized */

 	Node **genericdecls;

 	size_t ngenericdecls;

@@ -50,17 +46,23 @@

 	Htab *seqbase;

 };

+/* type params bound at the current point */

+Htab **tybindings;

+size_t ntybindings;

+

 static void infernode(Inferstate *st, Node **np, Type *ret, int *sawret);

 static void inferexpr(Inferstate *st, Node **np, Type *ret, int *sawret);

 static void inferdecl(Inferstate *st, Node *n);

-static void typesub(Inferstate *st, Node *n, int noerr);

+

+static Type *tf(Inferstate *st, Type *t);

 static void tybind(Inferstate *st, Type *t);

-static Type *tyfix(Inferstate *st, Node *ctx, Type *orig, int noerr);

 static void bind(Inferstate *st, Node *n);

 static void tyunbind(Inferstate *st);

 static void unbind(Inferstate *st, Node *n);

+

 static Type *unify(Inferstate *st, Node *ctx, Type *a, Type *b);

-static Type *tf(Inferstate *st, Type *t);

+static Type *tyfix(Inferstate *st, Node *ctx, Type *orig, int noerr);

+static void typesub(Inferstate *st, Node *n, int noerr);

 static void ctxstrcall(char *buf, size_t sz, Inferstate *st, Node *n)

 {

@@ -301,8 +303,8 @@

 {

 	ssize_t i;

-	for (i = st->ntybindings - 1; i >= 0; i--) {

-		if (htget(st->tybindings[i], t->pname))

+	for (i = ntybindings - 1; i >= 0; i--) {

+		if (htget(tybindings[i], t->pname))

 			return 1;

 	}

 	return 0;

@@ -511,26 +513,48 @@

 	return t;

 }

+static Type *remapping(Type *t)

+{

+	Stab *ns;

+	Type *lu;

+	int i;

+

+	switch (t->type) {

+	case Tyunres:

+		ns = curstab();

+		if (t->name->name.ns) {

+			ns = getns(file, t->name->name.ns);

+		}

+		if (!ns)

+			fatal(t->name, "could not resolve namespace \"%s\"",

+					t->name->name.ns);

+		if (!(lu = gettype(ns, t->name)))

+			fatal(t->name, "could not resolve type %s", tystr(t));

+		return lu;

+	case Typaram:

+		for (i = ntybindings - 1; i >= 0; i--) {

+			lu = htget(tybindings[i], t->pname);

+			if (lu)

+				return lu;

+		}

+	default:

+		break;

+	}

+	return NULL;

+}

+

 /* Look up the best type to date in the unification table, returning it */

 static Type *tylookup(Type *t)

 {

 	Type *lu;

-	Stab *ns;

 	assert(t != NULL);

 	lu = NULL;

 	while (1) {

-		if (!tytab[t->tid] && t->type == Tyunres) {

-			ns = curstab();

-			if (t->name->name.ns) {

-				ns = getns(file, t->name->name.ns);

-			}

-			if (!ns)

-				fatal(t->name, "could not resolve namespace \"%s\"",

-						t->name->name.ns);

-			if (!(lu = gettype(ns, t->name)))

-				fatal(t->name, "could not resolve type %s", tystr(t));

-			tytab[t->tid] = lu;

+		if (!tytab[t->tid]) {

+			lu = remapping(t);

+			if (lu && lu != t)

+				tytab[t->tid] = lu;

 		}

 		if (!tytab[t->tid])

@@ -749,7 +773,7 @@

 	Htab *bt;

 	bt = mkht(strhash, streq);

-	lappend(&st->tybindings, &st->ntybindings, bt);

+	lappend(&tybindings, &ntybindings, bt);

 	putbindings(st, bt, t);

 }

@@ -759,7 +783,7 @@

 	size_t i;

 	bt = mkht(strhash, streq);

-	lappend(&st->tybindings, &st->ntybindings, bt);

+	lappend(&tybindings, &ntybindings, bt);

 	if (t->type == Tygeneric)

 		for (i = 0; i < t->ngparam; i++)

 			putbindings(st, bt, t->gparam[i]);

@@ -780,7 +804,7 @@

 		return;

 	st->ingeneric++;

 	bt = mkht(strhash, streq);

-	lappend(&st->tybindings, &st->ntybindings, bt);

+	lappend(&tybindings, &ntybindings, bt);

 	putbindings(st, bt, n->decl.type);

 	if (n->decl.init)

@@ -793,15 +817,15 @@

 {

 	if(!n->decl.isgeneric)

 		return;

-	htfree(st->tybindings[st->ntybindings - 1]);

-	lpop(&st->tybindings, &st->ntybindings);

+	htfree(tybindings[ntybindings - 1]);

+	lpop(&tybindings, &ntybindings);

 	st->ingeneric--;

 }

 static void tyunbind(Inferstate *st)

 {

-	htfree(st->tybindings[st->ntybindings - 1]);

-	lpop(&st->tybindings, &st->ntybindings);

+	htfree(tybindings[ntybindings - 1]);

+	lpop(&tybindings, &ntybindings);

 }

 /* Constrains a type to implement the required constraints. On

@@ -2001,10 +2025,10 @@

 		break;

 	case Nfunc:

 		setsuper(n->func.scope, curstab());

-		if (st->ntybindings > 0)

+		if (ntybindings > 0)

 			for (i = 0; i < n->func.nargs; i++)

-				putbindings(st, st->tybindings[st->ntybindings - 1],

-						n->func.args[i]->decl.type);

+				putbindings(st, tybindings[ntybindings - 1],

+					n->func.args[i]->decl.type);

 		pushstab(n->func.scope);

 		inferstab(st, n->func.scope);

 		inferfunc(st, n);

@@ -2630,7 +2654,7 @@

 	postcheck(&st);

 	/* and replace type vars with actual types */

-	assert(st.ntybindings == 0);

+	assert(ntybindings == 0);

 	typesub(&st, file, 0);

 	specialize(&st, file);

 	verify(&st, file);