my attempt to do the exercises in sicp.

Tuesday, July 1, 2008

sicp exercise 1.42

;  Exercise 1.42.  Let f and g be two one-argument functions. The composition f after g is defined to be
;  the function x  f(g(x)). Define a procedure compose that implements composition. For example, if inc
;  is a procedure that adds 1 to its argument,

;  ((compose square inc) 6)
;  49

(define (compose f g)
  (lambda (x)
    (f (g x))))

(define (square x) (* x x))

(define (inc x) (+ x 1))

(display ((compose square inc) 6)) (newline)

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