static void initVariantInstance(InstancePtr x) {
EnvPtr env = new Env(x->env);
const vector<PatternVar> &pvars = x->patternVars;
for (unsigned i = 0; i < pvars.size(); ++i) {
if (pvars[i].isMulti) {
MultiPatternCellPtr cell = new MultiPatternCell(NULL);
addLocal(env, pvars[i].name, cell.ptr());
}
else {
PatternCellPtr cell = new PatternCell(NULL);
addLocal(env, pvars[i].name, cell.ptr());
}
}
PatternPtr pattern = evaluateOnePattern(x->target, env);
ObjectPtr y = derefDeep(pattern);
if (y.ptr()) {
if (y->objKind != TYPE)
error(x->target, "not a variant type");
Type *z = (Type *)y.ptr();
if (z->typeKind != VARIANT_TYPE)
error(x->target, "not a variant type");
VariantType *vt = (VariantType *)z;
vt->variant->instances.push_back(x);
}
else {
if (pattern->kind != PATTERN_STRUCT)
error(x->target, "not a variant type");
PatternStruct *ps = (PatternStruct *)pattern.ptr();
if ((!ps->head) || (ps->head->objKind != VARIANT))
error(x->target, "not a variant type");
Variant *v = (Variant *)ps->head.ptr();
v->instances.push_back(x);
}
}
void patternPrint(llvm::raw_ostream &out, PatternPtr x)
{
switch (x->kind) {
case PATTERN_CELL : {
PatternCell *y = (PatternCell *)x.ptr();
out << "PatternCell(" << y->obj << ")";
break;
}
case PATTERN_STRUCT : {
PatternStruct *y = (PatternStruct *)x.ptr();
out << "PatternStruct(" << y->head << ", " << y->params << ")";
break;
}
default :
assert(false);
}
}