On Oct 28, 2011, at 1:23 PM, Joe Marshall wrote:
> On the other hand, providing code to demonstrate a particular way
> of generalizing may carry more weight than a simple assertion of
> incorrectness. But I could be wrong here as well.
OK, here's a variant of "binary->nary" that produces the results we want when
"op" has contract "X X -> boolean" rather than "X X -> X"
(define (binary->nary relop)
(letrec ((f (lambda args
(or (empty? args)
(empty? (rest args))
(and (relop (first args) (second args))
(apply f (rest args)))))))
f))
This applies relop to each successive (overlapping) pair of elements and "and"s
the results.
Stephen Bloch
sbl...@adelphi.edu
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