10 lines
221 B
Common Lisp
10 lines
221 B
Common Lisp
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(defun plusp (n) (> n 0))
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(defun zerop (n) (= n 0))
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(defmacro nif (expr pos zero neg)
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(let ((g (gensym)))
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`(let ((,g ,expr))
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(cond ((plusp ,g) ,pos)
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((zerop ,g) ,zero)
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(t ,neg)))))
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