return constructorsNeededBy(sym).contains(sym);
HashSet constrs = constructorsNeededBy(sym); if (constrs.contains(sym)) return true; Iterator constrsIt = constrs.iterator(); while (constrsIt.hasNext()) { Symbol constr = (Symbol)constrsIt.next(); if (constr.isAbstractType()) return true; } return false;
        private boolean isCyclic(Symbol sym) {            return constructorsNeededBy(sym).contains(sym);        }