Forward declaration of a nested class

[Jiri Palecek]

Hi
How can I (can I?) forward declare a nested class without having
to define the class it is nested in? Like this

class A;
class A::B;
void f(A::B*);

Thanks in advance

Jiri Palecek
japeleck at web dot de

 

[Victor Bazarov]

How can I (can I?) forward declare a nested class without having
to define the class it is nested in?

You cannot.

 

[Jonathan Turkanis]

Hi
How can I (can I?) forward declare a nested class without having
to define the class it is nested in? Like this

class A;
class A::B;
void f(A::B*);

Thanks in advance

One possible workaround is to define f to be a template

template<typename T>
void f(T*);

where f only relies on properties of T which A::B is known to satisfy.
If f(A::B) must coexist with other overloads of f(), you might be able
to use boost::enable_if.

Jonathan