using lambda instead of let in scheme

Posted by Radagaisus on Stack Overflow See other posts from Stack Overflow or by Radagaisus
Published on 2010-05-25T16:39:32Z Indexed on 2010/05/25 16:41 UTC
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lambda

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Scheme

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sicp

Hey,

In SICP 1.2.1 there is a function that makes a rational number, as follow:

(define (make-rat n d)
  (let ((g (gcd n d)))
    (cons (/ n g) (/ d g))))

I'm just curious how you can implement the same thing using lambda instead of let, without calling GCD twice. I couldn't figure it out myself.

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