Basic Object System
(BOS) A C-callable library that implements the notion of object and which uses Tcl as its interpreter for interpreted methods (you can have "compiled" methods in C, and mix compiled and interpreted methods in the same object, plus lots more). You can subclass and mix in existing objects using BOS to extend, among other things, the set of tk widgets. BOS is a class-free object system, also called a prototype-based object system; it is modelled loosely on the Self system from Stanford University.
Version 1.31 by Sean Levy <Sean.Levy@cs.cmu.edu>.