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\begin{document}

\mytitle{9/19/90}

Given the supporting code for the function {\bf match}, the code for
the function {\bf match-variable} is very simple:

\begin{verbatim}
(defun match-variable (p d bindings)
  (add-binding p d bindings))
\end{verbatim}

Using this definition of {\bf match-variable} produces the correct
behavior of {\bf match}: 

\begin{verbatim}
> (match '(a (? x) c) '(a b c))
((X B))

> (match '((? x) d e) '((a b c) d e))
((X (A B C)))

> (match '(a b (c d (? x) f)) '(a b (c d e f)))
((X E))
\end{verbatim}

\end{document}


