我们从一个分包商处收到代码，主要执行以下操作:classCallable{public:voidoperator()(intx){printf("x=%d\n",x);}};templateclassUsesTheCallable{public:UsesTheCallable(Tcallable):m_callable(NULL){m_callable=&callable;}~UsesTheCallable(){}voidcall(){(*m_callable)(5);}private:T*m_callable;};这让我觉得这是未定义的代码......它们按值将T传递给UsesThe