XLISP is a family of Lisp implementations written by David Betz.
The first version was a Lisp with object-oriented extensions for computers with limited power. The second version (XLISP 2.0) moved toward Common Lisp, but was by no means a complete implementation. After a long period of inactivity, the author released a new version based on XSCHEME, his Scheme implementation. The most current version follows the Scheme R3RS standard.
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