procyberian/emacs
2
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Add seq-random-elt to seq.el

Browse source 
* lisp/emacs-lisp/seq.el (seq-random-elt): Add function to return a
  random element from it's sequence parameter.

* test/lisp/emacs-lisp/seq-tests.el (test-seq-random-elt-take-all
  test-seq-random-elt-return-nil): Test the new function

* doc/lispref/sequences.texi: Document the new function
This commit is contained in:
Damien Cassou 2016-10-21 07:53:08 +02:00 • committed by Nicolas Petton
parent 26ccd19269
commit bd22beb6e4
3 changed files with 45 additions and 1 deletions
Download patch file Download diff file Expand all files Collapse all files

9
lisp/emacs-lisp/seq.el
View file

@ -4,7 +4,7 @@
;; Author: Nicolas Petton <nicolas@petton.fr>
;; Keywords: sequences
;; Version: 2.18
;; Version: 2.19
;; Package: seq
;; Maintainer: emacs-devel@gnu.org
@ -476,6 +476,13 @@ SEQUENCE must be a sequence of numbers or markers."
"Return element of SEQUENCE at the index N.
If no element is found, return nil."
(ignore-errors (seq-elt sequence n)))
(cl-defgeneric seq-random-elt (sequence)
"Return a random element from SEQUENCE.
Return nil if SEQUENCE is nil."
(if (seq-empty-p sequence)
(error "Sequence cannot be empty")
(seq-elt sequence (random (seq-length sequence)))))
;;; Optimized implementations for lists