CS 342 Lecture -*- Outline -*-

* Lambda the Ultimate
	with lambda, you can do everything!

** the Y-combinator can be used to make recursive functions
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(define oh-no
  (Y
    (lambda (recurse)
      (lambda (x)
	(recurse x)))))

(define length
  (Y
   (lambda (recurse)
    (lambda (l)
     (cond
	((null? l) 0)
	(else (+ 1 (recurse (cdr l)))))))))
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** closures can be used to delay evaluation
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(define (if-closures e1 c2 c3)
  (if e1 (c2) (c3)))

(if-closures #t (lambda () (+ 3 4)) (lambda () (oh-no #t)))
; Value: 7
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