Method become

gecode/set/var-imp/integerset.hpp:210–221

  }

  forceinline void
  BndSet::become(Space& home, const BndSet& that) {
    if (fst()!=nullptr) {
      assert(lst()!=nullptr);
      assert(fst()!= that.fst());
      fst()->dispose(home,lst());
    }
    fst(that.fst());
    lst(that.lst());
    _size = that.size();
    assert(isConsistent());
  }

  forceinline bool
  BndSet::in(int i) const {