3 ms·
(Stolen) from Rainer Joswig's post[1] at Reddit: Modern version: (defun collapse (l) (cond ((atom l) (cons l nil)) ((null (cdr l))
by fogus 16y ago
(Stolen) from Rainer Joswig's post[1] at Reddit:
Modern version:
(defun collapse (l)
(cond ((atom l) (cons l nil))
((null (cdr l))
(cond ((atom (car l)) l)
(t (collapse (car l)))))
(t (append (collapse (car l))
(collapse (cdr l))))))
(collapse '(((A B) ((C))) ((D (E F)) (G) ((H)))))
;=> (A B C D E F G H)
[1]: http://www.reddit.com/r/lisp/comments/fpfnf/an_early_lisp_program_circa_feb_1960/ http://www.reddit.com/r/lisp/comments/fpfnf/an_early_lisp_pr...
- mahmud 16y agoBetter known as FLATTEN.