sqrt.scm

#!/usr/bin/guile -s
!#

(define (sqrt x)
  (define (good-enough? guess)
    (< (abs (- guess (/ x guess))) .001))
  (define (improve guess)
    (/ (+ guess (/ x guess)) 2))
  (define (try guess)
    (if (good-enough? guess)
	guess
	(try (improve guess))))
  (try 1.0))

(display (sqrt 3))
(newline)