27 lines
734 B
Scheme
27 lines
734 B
Scheme
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;; -*- geiser-scheme-implementation: guile -*-
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(define (make-goldilocks smallest-ok biggest-ok)
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(define (goldilocks n)
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(cond ((< n smallest-ok) 'too-small)
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((> n biggest-ok) 'too-big)
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(else 'just-right)))
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goldilocks)
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(make-goldilocks 10 30) ; #<procedure goldilocks (n)>
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(define goldi (make-goldilocks 10 30)) ; #<unspecified>
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(goldi 7) ; too-small
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(goldi 256) ; too-big
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(goldi 22) ; just-right
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(define (abstract-cons car-data cdr-data)
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(lambda (method)
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(cond ((eq? method 'car) car-data)
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((eq? method 'cdr) cdr-data)
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(else (error "Unknown method -- ABSTRACT-CONS" method)))))
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(define our-cons (abstract-cons 'foo 'bar))
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(our-cons 'car) ; foo
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(our-cons 'cdr) ; bar
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