mirrors/emacs
1
Fork 0
mirror of git://git.sv.gnu.org/emacs.git synced 2025-12-15 18:40:39 -08:00
Code Issues Projects Releases Wiki Activity

* subr.el (butlast): Document what an omitted N means.

Browse source 
* subr.el (butlast): Document what an omitted N means.
(nbutlast): Ditto.

Fixes: debbugs:13437
This commit is contained in:
Lars Ingebrigtsen 2014-01-31 23:54:29 -08:00
parent cc477daa01
commit 79278d0313
1 changed files with 5 additions and 2 deletions
Download patch file Download diff file Expand all files Collapse all files

7
lisp/subr.el
View file

@ -364,12 +364,15 @@ If N is bigger than the length of LIST, return LIST."
(nthcdr (1- (safe-length list)) list))))
(defun butlast (list &optional n)
"Return a copy of LIST with the last N elements removed."
"Return a copy of LIST with the last N elements removed.
If N is omitted or nil, the last element is removed from the
copy."
(if (and n (<= n 0)) list
(nbutlast (copy-sequence list) n)))
(defun nbutlast (list &optional n)
"Modifies LIST to remove the last N elements."
"Modifies LIST to remove the last N elements.
If N is omitted or nil, remove the last element."
(let ((m (length list)))
(or n (setq n 1))
(and (< n m)