模板功能的特化可以是虚拟的吗？

Question

Something like, for example,

class A {
    template<typename T> T DoStuff();
    template<> virtual int DoStuff<int>() = 0;
};

Visual Studio 2010 says no, but I get a funny feeling that I simply messed up the syntax. Can explicit full specializations of a member function template be virtual?

Answer 1

Explicit specializations aren't legal within a class. Even if you could make it a partial specialization you would still run into the "templates can't be virtual" problem.

n3290, § 14.5.2 states:

A member function template shall not be virtual.

And gives this example:

template <class T> struct AA {
  template <class C> virtual void g(C); // error
  virtual void f(); // OK
};

Before going on to state that member function templates do not count for virtual overrides too.

Answer 2

According to C++98 Standard member function template shall not be virtual. http://www.kuzbass.ru:8086/docs/isocpp/template.html .

-3- A member function template shall not be virtual. [Example:

 template <class T> struct AA { template <class C> virtual void g(C); // error virtual void f(); // OK }; 

Answer 3

您可以通过使用常规非模板虚函数重载功能模板来获得类似的效果。