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Subtracting a number: `sub'

The expression $ m - n$ is evaluated by decrementing $ m$ $ n$-times.
\begin{lstlisting}[language=Scm]{} (define sub (lambda (m n) ((n pred) m))) \end{lstlisting}


\begin{lstlisting}[language=Scm]{} (ndisp! (sub three two)) --> 1 (ndisp! (sub four two)) --> 2 \end{lstlisting}


domain access counter Georg P. Loczewski 2004-03-05