Calling Member Functions
When you call a member function in a program you always specify an object usually by writing the object name and a dot before the function name (e.g. in_stream.open(“infile.dat”);)
the dot is called the dot operator and the object named before the dot is referred to as the calling object
One reason for naming the object is that the function can have some effect on the object
Another is to determine the meaning of the function name