C++ template partial specialization - specializing one member function only

Question

Bumped into another templates problem:

The problem: I want to partially specialize a container-class (foo) for the case that the objects are pointers, and i want to

Answer 1

I haven't seen this solution yet, using boost's enable_if, is_same and remove_pointer to get two functions in a class, without any inheritance or other cruft.

See below for a version using only remove_pointer.

#include 
#include 
#include 

template 
class foo
{
public:
    typedef typename boost::remove_pointer::type T_noptr;

    void addSome    (T o) { printf ("adding that object..."); }

    template
    void deleteSome (U o, typename boost::enable_if>::type* dummy = 0) { 
        printf ("deleting that object..."); 
    }
    template
    void deleteSome (U* o, typename boost::enable_if>::type* dummy = 0) { 
        printf ("deleting that PTR to that object..."); 
    }
};

A simplified version is:

#include 
#include 

template 
class foo
{
public:
    typedef typename boost::remove_pointer::type T_value;

    void addSome    (T o) { printf ("adding that object..."); }

    void deleteSome (T_value& o) { // need ref to avoid auto-conv of double->int
        printf ("deleting that object..."); 
    }

    void deleteSome (T_value* o) { 
        printf ("deleting that PTR to that object..."); 
    }
};

And it works on MSVC 9: (commented out lines that give errors, as they are incorrect, but good to have for testing)

void main()
{
   foo x;
   foo y;

   int a;
   float b;

   x.deleteSome(a);
   x.deleteSome(&a);
   //x.deleteSome(b); // doesn't compile, as it shouldn't
   //x.deleteSome(&b);
   y.deleteSome(a);
   y.deleteSome(&a);
   //y.deleteSome(b);
   //y.deleteSome(&b);
}