Extension:RandomSelection

**MediaWiki extensions manual**
RandomSelection; Release status: stable
Implementation	Tag, Parser function
Description	Displays a random option from the given set
Author(s)	Ross McClure; Jack Phoenix;
Latest version	3.0.0 (2018-09-09)
MediaWiki	1.43+
Database changes	No
	Parameters $wgRandomSelectionAllowUncached;
	Tags ‎<choose>; ‎<option>; ‎<choicetemplate>;
	Hooks used MagicWordwgVariableIDs; ParserFirstCallInit;
Licence	GNU General Public License 2.0 or later
Download	Download extension ; Git [?]: Browse repository (GitHub); Gerrit code review; Git commit log; Download source tarball;
Example	Example on Mises Wiki;
	Translate the RandomSelection extension if it is available at translatewiki.net

Translate this page

The RandomSelection extension allows for randomly-generated content inside your wiki; e.g. rotating images, random greetings, etc.

Installation

Download and move the extracted RandomSelection folder to your extensions/ directory.
Developers and code contributors should install the extension from Git instead, using:
```
cd extensions/
git clone https://gerrit.wikimedia.org/r/mediawiki/extensions/RandomSelection
```
Add the following code at the bottom of your LocalSettings.php file:
```
wfLoadExtension( 'RandomSelection' );
```
Done – Navigate to Special:Version on your wiki to verify that the extension is successfully installed.

Usage

Tags

To choose between one or more options, simply place each option inside an ‎<option> tag which are themselves placed inside ‎<choose> tags, like so:

<choose>
<option>This is the first choice.</option>
<option>This is the second choice.</option>
<option>And so on...</option>
</choose>

From each set of ‎<choose> tags, precisely one ‎<option> tag will be selected at random, and its contents shown. Anything can be placed inside of option tags: links, images, even templates.

However, template arguments will not be expanded due to T4257.

You can also have what is placed inside the option tags be sent as an argument to a template with the ‎<choicetemplate> tag, e.g.:

<choose>
<option>Template:Featured article/Elephant</option>
<option>Template:Featured article/Giraffe</option>
<option>Template:Featured article/Rhinoceros</option>
<choicetemplate>PageWithEditButton</choicetemplate>
</choose>

You could then create a [[Template:PageWithEditButton]] with these contents:

[{{canonicalurl:{{{1}}}|action=edit}} Edit] {{{{{1}}}}}

This is useful if you want to set up randomly rotating featured articles and have an edit button to allow the user to edit the featured article blurbs.

Parameters to choose

Parameter	Description
`uncached`	Disable caching for the chosen option
`before`	Put this text before the chosen option
`after`	Put this text after the chosen option

Since version 2.2.2 caching in the ‎<choose> tag is disabled only if the user specifies ‎<choose uncached>. Previously caching was disabled by default.

If you wanted to disable caching for the options, you should add the uncached parameter.

<choose uncached>
<option>This is the first choice.</option>
<option>This is the second choice.</option>
<option>And so on...</option>
</choose>

If you wanted to display one of three YouTube videos, you could try this (Extension:Widgets and Extension:YouTube required):

<choose before="{{#widget: YouTube|id=" after="}}">
<option>eR7-AUmiNcA</option><!--King of Anything-->
<option>cSCi7kCXKDA</option><!--Slipping Through My Fingers-->
<option>7n2d9XPsmmE</option><!--When Death Note Music Plays in My Car-->
</choose>

Parameters to option

Parameter	Description
`weight`	Weight of the option

If you'd like some options to be shown more often than others, you can add weight to the option tags, like so:

<choose>
<option weight="2">This option will be shown twice as often as a normal option.</option>
<option>By default, options have a weight of 1.</option>
<option weight="1.5">This option also has a weight of 1. Fractional portions are ignored.</option>
</choose>

Parser function

To choose between one or more options, simply place each option inside the #choose: parser function, like so:

{{#choose:
 This is the first choice.
 |This is the second choice.
 |And so on...
}}

From each choice divided by a pipe, precisely one choice will be selected at random, and its contents shown.

If you'd like some options to be shown more often than others, you can add weight as parameter names, like so:

{{#choose:
 2=This option will be shown twice as often as a normal option.
 |By default, options have a weight of 1.
 |1.5=This option also has a weight of 1. Fractional portions are ignored.
}}

If the option contains =, you have to escape it, by either replacing it with {{=}} or prefixing the option with 1=.

MediaWiki handles the first parameter differently: it is expanded before passed to the parser function. As a result, if the expanded result contains =, you have to escape it with 1= ({{=}} doesn't work).

Example:

{{#choose:2 + 2 = 4}} → 4
{{#choose:2 + 2 {{=}} 4}} → 4
{{#choose:1=2 + 2 = 4}} → 2 + 2 = 4