if (funType == null) {
break;
}
ConcreteType retType = createType(funType.getReturnType());
retType = createUnionWithSubTypes(retType);
ConcreteType newret = type.toFunction().getReturnSlot()
.getType().unionWith(retType);
((ConcreteScope) type.getScope()).declareSlot(
ConcreteFunctionType.RETURN_SLOT_NAME, n, newret);
}
scope.declareSlot(lhs.getLastChild().getString(), n, type);