Hiding private data members? (C++)

Question

Is there a way to hide private data members of a C++ class away from its users, in the cpp file? I think of the private members as part of the implementation and it seems a little backwards to declare them in the header file.

Answer 1

The "pimpl" idiom is how this is generally handled.

See

• http://www.gotw.ca/gotw/024.htm
• http://www.gotw.ca/gotw/028.htm
• http://herbsutter.com/gotw/_100/ (updated for C++11)

Answer 2

you want to use something like the PIMPL idiom

http://en.wikipedia.org/wiki/Opaque_pointer