模板定义与模板模板参数的类,可以专门化,例如,std :: vector <std :: string>或std :: map <std :: tree>

Question

我想创建一个模板类,它可以容纳容器和容器的任何组合.例如,a std::vector<std::string>或者std::map<std::tree>,例如.

我尝试了很多组合,但我必须承认模板的复杂性让我感到压力.我编译的关闭是这样的:

template <class Vector, template <typename, class Containee = std::string> class Container>
class GenericContainer
{
    Container<Containee> mLemario;
};

虽然它编译到目前为止,然后,当我想实例化它时,我遇到了很多错误.

MyContainer<std::vector, std::string> myContainer;

我是否使用正确的方法来创建这种类？

Answer 1

对于std::vector(等)@ songyuanyao提供了一个很好的答案.但既然你也提到过std::map,我会在网上添加一个@ songyuanyao回答的简单扩展.

#include <iostream>
#include <vector>
#include <string>
#include <map>

template <template <typename...> class Container, typename Containee = std::string, typename... extras>
class GenericContainer
{
    Container<Containee, extras ...> mLemario;
    // Use 'Containee' here (if needed) like sizeof(Containee) 
    // or have another member variable like: Containee& my_ref.
};

int main()
{
    GenericContainer<std::vector, std::string> myContainer1;
    GenericContainer<std::vector, std::string, std::allocator<std::string>> myContainer2; // Explicitly using std::allocator<std::string>
    GenericContainer<std::map, std::string, int> myContainer3; // Map: Key = std::string, Value = int
}