Full specialization of method template from class template
I know this subject should be pretty much dated by now, but I'm having a tough time with this specific case.
St开发者_运维技巧raight to the point, this is what I want to do:
enum MyEnum
{
E_1,
E_2
};
template <MyEnum T>
class MyClass
{
// method to be fully specialized
template <typename U>
void myMethod(U value);
};
// full specialization of method template from class template
// (or is this in fact partial, since I'm leaving T alone?)
template <MyEnum T>
template <>
void MyClass<T>::myMethod<int>(int value)
{
std::cout << value << '\n';
}
Is this possible?
C++03 [$14.7.3/18] says
In an explicit specialization declaration for a member of a class template or a member template that appears in namespace scope, the member template and some of its enclosing class templates may remain unspecialized, except that the declaration shall not explicitly specialize a class member template if its enclosing class templates are not explicitly specialized as well.
So you need to specialize the enclosing class too.
Something like this would work.
template <>
template <>
void MyClass<E_1>::myMethod<int>(int value)
{
std::cout << value << '\n';
}
Since you leave T, while specializing only function template, then what you're trying to do would be called partial specialization, because T is still templated and you can use it in your function. But unfortunately, partial template specialization of function (whether be it member function or non-member function) is not allowed. So your code would give compilation error.
Either you fully specialize by specializing the class template as well, or you don't at all.
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