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9re/revr.scm

Created September 21, 2011 16:22
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re-construction of 'reverse' with only foldr and cons
Raw
revr.scm
(define (foldr f z ls)
(if (null? ls)
z
(f (car ls)
(foldr f z (cdr ls)))))
(define (revr ls)
((foldr (lambda (x f)
(lambda (a)
(f (cons x a))))
(lambda (x) x)
ls)
'()))
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