Exp transDec(Absyn.TypeDec d) {
// 1st pass - handles the type headers
// Using a local hashtable, check if there are two types
// with the same name in the same (consecutive) batch
// of mutually recursive types. See test38.tig!
Hashtable hash = new Hashtable();
for (Absyn.TypeDec type = d; type != null; type = type.next) {
if (hash.put(type.name, type.name) != null) error(type.pos, "type redeclared");
type.entry = new Types.NAME(type.name);
env.tenv.put(type.name, type.entry);
}
// 2nd pass - handles the type bodies
for (Absyn.TypeDec type = d; type != null; type = type.next) {
Types.NAME name = (Types.NAME) type.entry;
name.bind(transTy(type.ty));
}
// check for illegal cycle in type declarations
for (Absyn.TypeDec type = d; type != null; type = type.next) {
Types.NAME name = (Types.NAME) type.entry;
if (name.isLoop()) error(type.pos, "illegal type cycle");
}
return translate.TypeDec();
}
ExpTy transExp(Absyn.RecordExp e) {
Types.NAME name = (Types.NAME) env.tenv.get(e.typ);
if (name != null) {
Type actual = name.actual();
if (actual instanceof Types.RECORD) {
Types.RECORD r = (Types.RECORD) actual;
return new ExpTy(translate.RecordExp(transFields(e.pos, r, e.fields)), name);
}
error(e.pos, "record type required");
} else error(e.pos, "undeclared type: " + e.typ);
return new ExpTy(translate.Error(), VOID);
}
ExpTy transExp(Absyn.ArrayExp e) {
Types.NAME name = (Types.NAME) env.tenv.get(e.typ);
ExpTy size = transExp(e.size);
ExpTy init = transExp(e.init);
checkInt(size, e.size.pos);
if (name != null) {
Type actual = name.actual();
if (actual instanceof Types.ARRAY) {
Types.ARRAY array = (Types.ARRAY) actual;
if (!init.ty.coerceTo(array.element)) error(e.init.pos, "element type mismatch");
return new ExpTy(translate.ArrayExp(size.exp, init.exp), name);
} else error(e.pos, "array type required");
} else error(e.pos, "undeclared type: " + e.typ);
return new ExpTy(translate.Error(), VOID);
}
