36 lines
1.2 KiB
Plaintext
36 lines
1.2 KiB
Plaintext
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---
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Test
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---
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Shows the usage of a static variable.
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''"Let Over Lambda Over Let Over Lambda"''
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| script | lisp interpreter fixture |
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| show | evaluate | !-
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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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-!|
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| show | evaluate | (setq my-counter (counter-class)) |
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| check | evaluate | (funcall my-counter) | 1 |
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| check | evaluate | (funcall my-counter) | 2 |
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| check | evaluate | (funcall my-counter) | 3 |
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| show | evaluate | (toggle-counter-direction) |
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| check | evaluate | (funcall my-counter) | 2 |
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| check | evaluate | (funcall my-counter) | 1 |
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| check | evaluate | (funcall my-counter) | 0 |
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| show | evaluate | (toggle-counter-direction) |
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| check | evaluate | (funcall my-counter) | 1 |
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| check | evaluate | (funcall my-counter) | 2 |
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| check | evaluate | (funcall my-counter) | 3 |
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