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ycombinator.scm
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ycombinator.scm
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;; (define fact
;; ((lambda (f)
;; (lambda (n)
;; (if (= n 0)
;; 1
;; (* n ((f f) (- n 1))))))
;; (lambda (f)
;; (lambda (n)
;; (if (= n 0)
;; 1
;; (* n ((f f) (- n 1))))))))
;; (define fact
;; ((lambda (f)
;; ((lambda (f-arg)
;; (lambda (n)
;; (if (= n 0)
;; 1
;; (* n (f-arg (- n 1))))))
;; (lambda (arg) ((f f) arg))))
;; (lambda (f)
;; ((lambda (f-arg)
;; (lambda (n)
;; (if (= n 0)
;; 1
;; (* n (f-arg (- n 1))))))
;; (lambda (arg) ((f f) arg))))))
;; (define F
;; (lambda (f-arg)
;; (lambda (n)
;; (if (= n 0)
;; 1
;; (* n (f-arg (- n 1)))))))
;; (define fact
;; ((lambda (f)
;; (F (lambda (arg) ((f f) arg))))
;; (lambda (f)
;; (F (lambda (arg) ((f f) arg))))))
(define Y
(lambda (F)
((lambda (x)
(F (lambda (arg) ((x x) arg))))
(lambda (x)
(F (lambda (arg) ((x x) arg)))))))
(define fact-gen
(lambda (f)
(lambda (n)
(if (= n 0)
1
(* n (f (- n 1)))))))
(define fact (Y fact-gen))
(define fib-gen
(lambda (f)
(lambda (n)
(if (< n 2)
n
(+ (f (- n 1))
(f (- n 2)))))))
(define fib (Y fib-gen))