inline
Syntax:
  inline int functionA( int i ) {
  ...
  }

The inline keyword requests that the compiler expand a given function in place, as opposed to inserting a call to that function. The inline keyword is a request, not a command, and the compiler is free to ignore it for whatever reason.

When a function declaration is included in a class definition, the compiler should try to automatically inline that function. No inline keyword is necessary in this case.