calling class name in the header file

c++

Solution

This is called a forward declaration. It means that there IS a class named CFoo, that will be defined later in the file (or another include). This is typically used for pointer members in classes, such as:

class CFoo;
class CBar {
    public:
        CFoo* object;
};

It is a hint to the C++ compiler telling it not to freak out that a type name is being used without being defined, even though it hasn't seen the full definition for CFoo yet.

Problem

I just stumbled a c++ code with a calling of a class name in the upper part of the header file for example ``` class CFoo; class CBar { .... }; ``` My question is, what is `class CFoo` for? Thanks alot!

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