17 lines
334 B
Common Lisp
17 lines
334 B
Common Lisp
(define-class queue
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(instance-variables vals))
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(define-method (queue 'initialize)
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(setq vals '())
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self)
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(define-method (queue 'push x)
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(setq vals (nconc vals (cons x nil))))
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(define-method (queue 'pop)
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(define val (car vals))
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(setq vals (cdr vals))
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val)
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(define-method (queue 'emptyp)
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(null vals))
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