A common error amongst new C++ programmers is to have operator= return void, a decision that seems reasonable unTIL you realize it prevents chains of assignment.

Here is an example implementation:

ANSI C supports const keyword in C99

The C++ language standard defines that if we try to delete a derived class object through a base class pointer and the base class has a nonvirtual destructor , the results are undefined

Library:

http://code.google.com/p/iphonegradientbuttons/

http://www.cimgf.com/2010/01/28/fun-with-uibuttons-and-core-animation-layers/