|13.5.7 Increment and decrement |
1 The user-defined function called operator++ implements the prefix and postfix ++ operator. If this function is
a member function with no parameters, or a non-member function with one parameter of class or enumeration
type, it defines the prefix increment operator ++ for objects of that type. If the function is a member function
with one parameter (which shall be of type int) or a non-member function with two parameters (the second
of which shall be of type int), it defines the postfix increment operator ++ for objects of that type. When
the postfix increment is called as a result of using the ++ operator, the int argument will have value zero.