Full specialization of template member function

[pascal.cathier]

Is it possible to fully specialize a template member function? If not,
why is that so? The following code fails to compile with GCC:

class A
{
public:
template < typename T >
void foo() {}

template <>
void foo<int>() {}
};

int main(int argc, char * argv[])
{
A a;
a.foo<void>();
a.foo<int>();
}

I can still wrap these functions 'foo' as the operator() of a template
class that I can then specialize to achieve the same goal, but I would
rather not if I can avoid to.

Thanks

B.

 

[Victor Bazarov]

Is it possible to fully specialize a template member function? If not,
why is that so? The following code fails to compile with GCC:

class A
{
public:
template < typename T >
void foo() {}

template <>
void foo<int>() {}

I believe the specialisation has to be defined outside the class.

};

Move it here:

template <>

int main(int argc, char * argv[])
{
A a;
a.foo<void>();
a.foo<int>();
}

I can still wrap these functions 'foo' as the operator() of a template
class that I can then specialize to achieve the same goal, but I would
rather not if I can avoid to.

V

 

[Rolf Magnus]

Is it possible to fully specialize a template member function?
If not, why is that so? The following code fails to compile with GCC:

class A
{
public:
template < typename T >
void foo() {}

template <>
void foo<int>() {}
};

int main(int argc, char * argv[])
{
A a;
a.foo<void>();
a.foo<int>();
}

I can still wrap these functions 'foo' as the operator() of a template
class that I can then specialize to achieve the same goal, but I would
rather not if I can avoid to.

Try:

class A
{
public:
template < typename T >
void foo() {}
};

template <>
void A::foo<int>() {}

 

[pascal.cathier]

Thanks... Is there a way to do the same thing with a templated class
though? It seems that the following does not work:

template < typename U >
class A
{
public:
template < typename T >
void foo();
};

template < typename U >
template < typename T >
void A<U>::foo() {}

template < typename U >
template <>
void A<U>::foo<int>() {}



Rolf Magnus a écrit :

Is it possible to fully specialize a template member function?
If not, why is that so? The following code fails to compile with GCC:

class A
{
public:
template < typename T >
void foo() {}

template <>
void foo<int>() {}
};

int main(int argc, char * argv[])
{
A a;
a.foo<void>();
a.foo<int>();
}

I can still wrap these functions 'foo' as the operator() of a template
class that I can then specialize to achieve the same goal, but I would
rather not if I can avoid to.

Try:

class A
{
public:
template < typename T >
void foo() {}
};

template <>
void A::foo<int>() {}

 

[Victor Bazarov]

Thanks... Is there a way to do the same thing with a templated class
though? It seems that the following does not work:

template < typename U >
class A
{
public:
template < typename T >
void foo();
};

template < typename U >
template < typename T >
void A<U>::foo() {}

template < typename U >
template <>
void A<U>::foo<int>() {}

Please don't top-post.

To answer your question, no, to specialise a member of a template class
you need to first specialise the class itself. It's a limitation of the
language.

Get a good book on templates. I suggest "C++ Templates" by Vandevoorde
and Josuttis.

V