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Hello gurus,

I have a template function with three types, I want to use the second
template to specify a class pointer or an auto_ptr (or a smart pointer,
etc). However seems I can not work with the latter, only plain naked
pointers are accepted. Is there any workaround? Thanks and happy new
year!
-Grace

#include <stdio.h>
#include <stdlib.h>
#include <string>
#include <memory>

using namespace std;

class A
{
public:
int m_i;
A(int j): m_i(j) {}

void foo(int k) { printf("in A, k=%d\n", k); }
void foo_d(double f) { printf("in A, k=%f\n", f);}
void foo2(int k) { printf("in A, k=%d\n", k); }
};

class B
{
public:
int m_i;
B(int j): m_i(j) {}

void foo(int k) { printf("in B k=%d\n", k); }
void foo2(int k) { printf("in B k=%d\n", k); }
};

// this is a class template usage, first class type,
//2nd a type pointer, 3rd input parameter type.
template <typename T, typename TPTR, typename INTYPE>
void AssignValue(TPTR& ptr, void (T::*method)(INTYPE), INTYPE in)
{
(ptr->*method)(in); //call a method, given the input parameter.
return;
}

typedef class A* A_PTR;
typedef class B* B_PTR;
typedef auto_ptr<A> A_PTR2;

int main()
{
A* a = new A(1);
AssignValue<A, A_PTR, int> (a, &A::foo, 20 );
AssignValue<A, A_PTR, double> (a, &A::foo_d, 20.20 );

B* b = new B(1);
AssignValue<B, B_PTR, int>(b, &B::foo2, -10);

auto_ptr<A> aa(new A(10));
AssignValue<A, A_PTR2, int>(aa, &A::foo, -10000);
/* Error above, can not compile, complaining no match for
`std::auto_ptr<A>& ->* void (A::*&)(int)' operator */

return 0;
}

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