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June 21, 2018 19:44
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Return the sequence created by calling fn on each element of seq, until the result is NIL
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| (defun while (fn seq) | |
| "Evaluates to the sequence that results from calling fn on each element of seq, until the result is NIL" | |
| (labels ((aux (seq acc) | |
| (if (null seq) acc | |
| (let ((val (funcall fn (first seq)))) | |
| (if val | |
| (aux (rest seq) (cons val acc)) | |
| acc))))) | |
| (aux seq nil))) |
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I'm not sure if this is utilities worthy, but I want to save it just in case.