The new programming languages derived from Lisp are generally not
described algorithmically. We propose a notation devoted to the
description of implementations of LISP interpreters. This notation is
an extension of LISP symbolic expression pattern matching, and does
not presuppose the prior existence of a LISP interpreter as a
subsystem. It is used here to define the interpreter of a subset of
the CONNIVER language. This subset and the LISP interpreter are
implemented at the same level of description, their union defines a
new LISP system: VLISP.