14 lines
331 B
Common Lisp
14 lines
331 B
Common Lisp
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(let ((direction 'up))
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(defun toggle-counter-direction ()
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(setq direction
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(if (eq direction 'up)
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'down
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'up)))
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(defun counter-class ()
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(let ((counter 0))
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(lambda ()
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(if (eq direction 'up)
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(setq counter (+ counter 1))
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(setq counter (- counter 1)))))))
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