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Comparing two numbers: `equaln'
This abstraction can only be used to compare Church Numerals.
To compare other objects like symbols, strings or closures
`equalx' has to be used, one of the primitive functions
introduced by the extension of A++.
![\begin{lstlisting}[language=Scm]{}
(define equaln (lambda (m n)
(land (zerop (sub m n))
(zerop (sub n m)))))
\end{lstlisting}](img111.gif)
![\begin{lstlisting}[language=Scm]{}
(bdisp! (equaln two three))
--> false
(bdisp! (equaln two two))
--> true
\end{lstlisting}](img112.gif)
Georg P. Loczewski
2004-03-05