Thursday, August 25, 2005

Pascal Costanza has posted to comp.lang.lisp about the first release of ContextL, a non-trivial example of using the CLOS MOP providing constructions for context oriented programming. The ContextL website has more information including an overview paper on it. From the overview paper: We present ContextL, a language extension for the Common Lisp Object System that allows for Context-oriented Programming. It provides means to associate partial class and method definitions with layers and to activate such layers in the control flow of a running program. ... This has the effect that the behaviour of a program can be modified according to the context of its use without the need to mention such context dependancies in the affected base program. We illustrate these ideas by describing a way to a) provide different UI views on the same object while b) keeping the conceptual simplicity of OOP that objects know themselves how to behave, in this case how to display themselves. 1:07:45 PM