InferredType duplicate() {
List<InferredType> newBranches = new ArrayList<InferredType>();
for (InferredType branch : unionTypes) {
newBranches.add(branch.duplicate());
}
return new UnionType(newBranches);
}
InferredType duplicate() {
List<InferredType> newElts = new ArrayList<InferredType>();
for (InferredType elt : structTypes) {
newElts.add(elt.duplicate());
}
return new StructType(newElts);
}