C ++等同于使用 用于Java参数/返回类型

enable_if

template<typename T, typename std::enable_if<std::is_base_of<MyClass, T>::value>::type* = nullptr>T Foo(T bar){    return T();}

例如：

class MyClass{public:    int a = 1;};class Derived : public MyClass{public:    int b = 2;};class NotDerived{public:    int b = 3;};template<typename T, typename std::enable_if<std::is_base_of<MyClass, T>::value>::type* = nullptr>T Foo(T bar){    return T();}int main(){    Derived d;    NotDerived nd;    std::cout << Foo(d).b << std::endl;; // works    //std::cout << (Foo(nd)).b << std::endl;; //compiler error    return 0;}

现场演示