35 lines
540 B
Scheme
35 lines
540 B
Scheme
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;; -*- geiser-scheme-implementation: guile -*-
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(define chest 'sword)
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chest ; sword
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(set! chest 'gold) ; #<unspecified>
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chest ; gold
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(define (make-countdown n)
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(lambda ()
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(define last-n n)
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(if (zero? n)
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0
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(begin
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(set! n (- n 1))
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last-n))))
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(define cdown (make-countdown 3))
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(cdown) ; 3
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(cdown) ; 2
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(cdown) ; 1
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(cdown) ; 0
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(cdown) ; 0
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(define vec (vector 'a 'b 'c))
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vec ; #(a b c)
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(vector-ref vec 1) ; b
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(vector-set! vec 1 'boop)
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(vector-ref vec 1) ; boop
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vec ; #(a boop c)
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