智能指针作为模板参数并校验是否子类

#include 
#include 

// 智能指针作为模板参数，并判断该智能指针管理的类型是否为指定类的子类
struct Base{};

struct Derived: Base{

};

struct Derived1{

};

// 使用enable_if和is_base_of结合判断，T::element_type为智能指针所管理的对象类型，需要加typename
template <typename T, typename = std::enable_if_t<std::is_base_of_v<Base,typename T::element_type>>>
void Convert(T elem){
    std::cout<<"T is subClass of Base"<<std::endl;
}


// 利用static_assert
template <typename T>
void Convert_Assert(T elem){
    static_assert(std::is_base_of_v<Base, typename T::element_type>, "T is not subClass of Base");
    std::cout<<"T is subClass of Base"<<std::endl;
}


int main(){
    std::shared_ptr<Derived> son = std::make_shared<Derived>();
    Convert(son);
    Convert_Assert(son);

    std::shared_ptr<Derived1> notSon = std::make_shared<Derived1>();

    // Convert(notSon); error
    // Convert_Assert(notSon); error
    return 0;
}
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