考虑以下代码。是否保证Derived<int>::foo()
会被实例化?foo()
是虚拟的,由基类的非虚拟函数调用。
#include <iostream>
class Base
{
public:
void bar() { foo(); }
private:
virtual void foo() = 0;
};
template <typename T> class Derived: public Base
{
public:
Derived(T t_) : t(t_) {}
private:
void foo() override { std::cout << t; }
T t;
};
Derived<int> make_obj()
{
return Derived<int>(7);
}