当使用赋值运算符重载时，新对象不能在operator =（）之外访问，

问题描述

我有一个队列的实现，需要写一个赋值运算符重载。

I have an implementation of a Queue which requires writing an assignment operator overload.

Queue& Queue::operator= (const Queue& rhs){
  if(this->head == rhs.head) return *this;

  Queue * newlist;
  if(rhs.head == NULL){ 
    // copying over an empty list will clear it.
    this->clear();
    return * newlist;
  }

  newlist = new Queue(rhs);
  cout << "made new queue" << endl;

  cout << "new list : " << * newlist << endl;
  return * newlist;
}

我遇到的问题是，当我离开此函数时， 新列表的内容不再可访问。

The problem I'm running into is that when I leave this function, the contents of newlist are no longer accessible. How is an operator=() function supposed to look?

编辑：
queue.h：

queue.h:

class Queue : public LinkedList {
protected:
    unsigned maxSize;

public:
    Queue(unsigned N = -1);
    Queue(const Collection& collection, unsigned N = -1);
    ~Queue();
    Queue(const Queue& obj);
    Queue& operator= (const Queue& rhs);
    friend std::ostream& operator<<(std::ostream& ostream, const Queue &rhs);
    bool add(myType element);
    myType element();
    bool offer(myType element);
    myType peek();
    myType poll();
    myType remove();

};

推荐答案

> operator = 应该使用 rhs （* this） c>，然后逐字返回（* this）。

An operator= is supposed to modify the internal object (*this) with the values of rhs and then literally return (*this).

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