Oaklisp

Oaklisp is a message based portable object-oriented Scheme developed by Kevin J. Lang and Barak A. Pearlmutter while Computer Science PhD students at Carnegie Mellon University. Oaklisp uses a superset of Scheme syntax. It is based on generic operations rather than functions, and features anonymous classes, multiple inheritance, a strong error system, setters and locators for operations, and a facility for dynamic binding.

Version 1.2 includes an interface, bytecode compiler, run-time system and documentation.