38 lines
623 B
Scheme
38 lines
623 B
Scheme
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; Copyright (c) 1993, 1994 Richard Kelsey and Jonathan Rees. See file COPYING.
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(define-generic g &g)
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(define-method &g ((x :number)) 'win)
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(define-method &g ((n :integer))
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(if (= n 13)
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(next-method)
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'ok))
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(define-method &g ((s :symbol))
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(if (= s 13)
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(next-method)
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'ok))
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; (g 1/2) => 'win
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; (g 10) => 'ok
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; (g 13) => 'win
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(define-generic elt &elt)
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(define-method &elt ((x :vector) y)
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(vector-ref x y))
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(define-method &elt ((x :string) y)
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(string-ref x y))
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(define-method &elt ((x :list) y)
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(list-ref x y))
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; Generic length
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; (define-generic-function glength ((s :sequence)))
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