c++ - 如何扩展 stl 类以拥有自己的方法？

Question

我知道从 stl 类继承是一个坏主意。但是还有其他方法可以扩展它们吗？

假设为了提高可读性，我希望能够在我的向量上调用“add”方法，而不是可读性较差的“push_back”。

或者我想在我的 std::map 中添加一个简单的 hasKey 方法。

除了创建一个以 std::vector 作为成员的整个包装器类，将每个函数调用从我的包装器传递给向量之外，还有什么方法可以做到这一点？

Answer 1

You should use free functions:

template<typename... Args>
bool has_key(std::map<Args...> const& map, typename std::map<Args...>::key_type key) {
  return map.find(key) != map.end();
}

Don't use inheritance if it's not necesarry. That's silly.

Answer 2

Once developers become accustomed to the STL names of things, having changed them will make the code less maintainable. This is generally a bad idea. In practice, since STL classes don't provide a virtual destructor, it's not possible to inherit from them and have good destruction behavior.