c++ partial specialization: How can I specialize this template to this template?

Question

#include 
using namespace std;

template 
class A {
public:
    void taunt() { cout << \"A\"; }
};

template 

        

Answer 1

Template specialization can't be used to reduce the number of template arguments, to do that you should use defaults for some of the arguments.

So in order to allow usage of only one argument, and make that usage hit your specialization, you need a default for the second argument, which is the same as the first argument:

#include 
using namespace std;

template 
class A {
public:
    void taunt() { cout << "A"; }
};

template 
class A {
public:
    void taunt() { cout << "B"; }
};

class B {};

class C {};

int main (int argc, char * const argv[]) {

    A a;
    a.taunt(); // Prints "B"

    return 0;
}