[Haskell-cafe] Re: The Worker/Wrapper Transformation

Achim Schneider wrote:

(define (cons x y) (lambda (m) (m x y)))

(define (car z) (z (lambda (p q) p)))

(define (cdr z) (z (lambda (p q) q)))

, which, just for completeness, can be of course also be done in Haskell: cons :: a -> b -> (a -> b -> c) -> c cons x y m = m x y car :: ((a -> b -> a) -> c) -> c car z = z $ \p q -> p cdr :: ((a -> b -> b) -> c) -> c cdr z = z $ \p q -> q Prelude> car $ cdr $ cdr $ cons 1 $ cons 2 $ cons 3 () 3 -- (c) this sig last receiving data processing entity. Inspect headers for past copyright information. All rights reserved. Unauthorised copying, hiring, renting, public performance and/or broadcasting of this signature prohibited.