Created
November 21, 2014 06:19
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[Lisp] Non-destructively replace #N element in list. (recursion way)
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| (defun rep-elt (list &optional n new) | |
| (cond ((null n) | |
| list) | |
| ((> n 0) | |
| (cons (car list) (rep-elt (cdr list) (1- n) new))) | |
| ((eq n 0) | |
| (cons new (cdr list)) | |
| ))) |
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