c++ - 删除向量或指针编译器错误

Question

我有以下功能，以前可以正常工作，但是，我不知道我做了什么，我开始得到一些奇怪的错误

容器是一个指针向量

template<typename Container>
void delete_collections(Container& c) 
{ 
    while(!c.empty()) 
    {
        delete c.back(); //<=== here
        c.back() = NULL;
        c.pop_back();    //<=== & here
    }
}

第一个错误

* *此行有多个标记

• （每个未声明的标识符都是
• `back' 未声明（首先使用这个

第二个错误

• `pop_back' 未声明（第一次使用

解决方案 我曾经错误地将映射传递给函数，但我希望编译器给出任何警告。

Answer 1

Just for the record, I would use a specialized container instead, take a look at e.g. Boost. Alternatively, store smart pointers where you don't have to call delete manually. Still, here's how to do it in a way that works with every container except maps:

template<typename container>
void delete_all(container& c) {
    for(typename container::const_iterator it=c.begin(), end=c.end(); it!=end; ++it)
        delete *it;
    c.clear();
}

With C++11, you could use auto, too, instead of typename container::const_iterator.