context orientation for Common Lisp

 ContextL provides the Common Lisp Object System with functionality
 for context orientation. It allows the definition of context-specific
 methods or class slots, so that methods act differently depending on
 the dynamic context they are executed in.
 .
 It further allows developers to rebind places (e.g. slots of objects)
 dynamically using the "dletf" framework that has previously been
 present in AspectL.