I know a typedef cannot be forward declared in C++, but I wonder what may be the best solution for the following problem. I have a header file which declares MyClass like this:
#include <TemplateClassHeaders>
struct MyStruct
{
// ...
}
typedef Really::Long::TemplateClassName<MyStruct> MyClass;
MyClass is used in many places, but mostly just as a pointer being passed through Qt signal-slot mechanism. A forward declaration would be all that’s needed, but since MyClass is a typedef that will not work. Is there a way to avoid adding myclass.h to every header which uses a pointer to MyClass?
10
You cannot forward-declare a typedef. But if you forward-declare the classes it relies on, both TemplateClassName and MyStruct, you should be able to define MyClass.
namespace Really {
namespace Long {
template <typename>
class TemplateClassName;
}
}
class MyStruct;
typedef Really::Long::TemplateClassName<MyStruct> MyClass;
MyClass *p = 0;
1