View source for Template talk:If preview

{{Permanently protected}}

== Merge with Ifpreview ==
{{ping|Evad37}} Should [[Template:Ifpreview]] be merged into this? They do the exact same thing, although {{tl|Ifpreview}} allows named arguments. That said, it's essentially unused, so maybe backwards compatibility doesn't matter. [[User:Daask|Daask]] ([[User talk:Daask|talk]]) 07:28, 28 March 2018 (UTC)

== Preview warning and hatnotes moving to templatestyles ==

Page watchers may be interested in {{slink|MediaWiki talk:Common.css|Preview warning and hatnotes moving to TemplateStyles}} [[User:Izno|Izno]] ([[User talk:Izno|talk]]) 23:57, 28 April 2021 (UTC)

== Fix documentation please ==
{{resolved}}
*/doc now says: "use the <code>main()</code>". Which is incorrect (should be: <code>main</code>).
: And: "use the <code>_warning()</code>". Which is incorrect (should be: <code>_warning</code>).


*<s>Also, there is no overview of parameters to be used. (how do I enter the _warning_text?)</s>.

:-[[User:DePiep|DePiep]] ([[User talk:DePiep|talk]]) 18:57, 20 June 2021 (UTC)
::resolved: this pertains to the Module documentation, not this template. -[[User:DePiep|DePiep]] ([[User talk:DePiep|talk]]) 07:53, 22 June 2021 (UTC)

== Use in module ==
'''Re: [[Module:If preview]]'''

I tried to use _warning() in [[Module:Authority control/sandbox]] but the warning is displayed in-situ and not at the top of the page where it should be. Am I doing something wrong? &mdash;&nbsp;Martin <small>([[User:MSGJ|MSGJ]]&nbsp;·&nbsp;[[User talk:MSGJ|talk]])</small> 16:34, 30 December 2022 (UTC)

:@[[User:Izno|Izno]] can you advise on this please - did it used to work or am just misremembering something? &mdash;&nbsp;Martin <small>([[User:MSGJ|MSGJ]]&nbsp;·&nbsp;[[User talk:MSGJ|talk]])</small> 10:59, 19 July 2023 (UTC)
::_warning has always been placed at the location where the warning would normally be emitted. If you want it to appear at the top of the article only, [[mw:Extension:Scribunto/Lua_reference_manual#mw.addWarning|mw.addWarning]] is the only function that does that. You may otherwise be confused here because outputs of _warning are most common due to infoboxes, which are always at the top of the page. [[User:Izno|Izno]] ([[User talk:Izno|talk]]) 16:14, 19 July 2023 (UTC)
:::Quite possible that I am misremembering! Did you consider using mw.addWarning rather than the REVISIONID hack?  &mdash;&nbsp;Martin <small>([[User:MSGJ|MSGJ]]&nbsp;·&nbsp;[[User talk:MSGJ|talk]])</small> 16:57, 19 July 2023 (UTC)
::::REVISIONID is the supported way to check for preview and is how both this system's warning and ifpreview worked before I touched it.
::::Besides that, because mw.addWarning appears in a different place than in situ, and I know that people have been sensitive on the point before, that would be a consensus-needed to change.
::::Identical messages are also de-duplicated somewhere in addWarning's call stack. I don't know how relevant that is generally. See [[Help_talk:Citation_Style_1/Archive_77#summary_messaging_in_the_preview_warning_header|some previous discussion for CS1]]. [[User:Izno|Izno]] ([[User talk:Izno|talk]]) 17:16, 19 July 2023 (UTC)
:::::Useful, thanks. It seems that addWarning does not work with the live preview, which is a serious limitation &mdash;&nbsp;Martin <small>([[User:MSGJ|MSGJ]]&nbsp;·&nbsp;[[User talk:MSGJ|talk]])</small> 17:43, 19 July 2023 (UTC)
::::::Yes, I suppose that's true. It might be worth a task to see if it's even feasible to act on that. [[User:Izno|Izno]] ([[User talk:Izno|talk]]) 18:42, 19 July 2023 (UTC)

== Template-protected edit request on 28 March 2024 ==

{{edit template-protected|Module:If preview|answered=yes}}
In the function <code><nowiki>p._warning</nowiki></code> please add before the return call:
<code><nowiki>mw.addWarning(warning)</nowiki></code>. This will put the preview warning at the top of the preview in addition to inline in the wikitext. [[User:Awesome Aasim|Awesome]] [[User_talk:Awesome Aasim|Aasim]] 23:29, 28 March 2024 (UTC)

:<s><nowiki>{{Done}}</nowiki></s>. [[User:SilverLocust|<small style="color:#667;background:#fff;border:2px solid;border-radius:.4em;padding:0 .3em">SilverLocust</small>]] [[User talk:SilverLocust|💬]] 19:54, 31 March 2024 (UTC)

::{{Reply|Awesome Aasim}} The [[Special:Diff/1216624147|edit has been reverted]] because it resulted in [[Module:Parameter validation/default config]] emitting erroneous preview warnings. Templates like [[Template:Marriage]] and any others with <syntaxhighlight lang="wikitext" inline>{{#invoke:Parameter validation|validateparams|module_options = Module:Parameter validation/default config}}</syntaxhighlight> would always give the incorrect preview warnings:
::{{tqb|Script warning: [[templatename]] used with unknown parameter(s): paramname. <br>Script warning: [[templatename]] used with deprecated parameter(s): paramname. <br>Script warning: [[templatename]] used with duplicate parameter(s): paramandvalue.}}
::(You can see the erroneous preview warnings with the example in the below quote box. Preview an edit of this section to see the warnings.) 
{{quotebox|{{marriage/sandbox|Example|2020}}}}
::Apparently the [[Module:Parameter_validation/default_config#L-11|options in the (default) config]] are evaluated when the <code>options</code> table is intially loaded in as a variable (i.e., before those options are actually needed, and even if they will not be needed), since those function calls aren't stored unevaluated in the table (e.g., as a string or sub-table). And evaluating those first three options involves calling <code>_warning</code> and thus (until the edit was reverted) calling <code>mw.addWarning</code>. 
::That being said, I am not presently sure how this should be fixed. [[User:SilverLocust|<small style="color:#667;background:#fff;border:2px solid;border-radius:.4em;padding:0 .3em">SilverLocust</small>]] [[User talk:SilverLocust|💬]] 06:00, 1 April 2024 (UTC) (and subsequently edited)
:::Additionally, in looking now at the section above this, there is a [[#c-MSGJ-20230719165700-Izno-20230719161400|comment]] that <code>mw.addWarning</code> should not be added here without consensus due to some previous sensitivity. (Part of why I thought this wouldn't be controversial was because [[Template:Preview warning/doc]] already said — erroneously — that the warning always appears at the top, and because it seemed self-evident that a "preview warning" should use MediaWiki's built-in preview warning function, <code>mw.addWarning</code>.) [[User:SilverLocust|<small style="color:#667;background:#fff;border:2px solid;border-radius:.4em;padding:0 .3em">SilverLocust</small>]] [[User talk:SilverLocust|💬]] 08:32, 1 April 2024 (UTC) (and subsequently edited)
::::That sounds like bad code to me. The only other thing I can think of is maybe a module that when preprocessed emits the preview warning. A warning should not be emitted if there is a code problem, so calling the function beforehand creates a ton of headaches. If the config needs to fetch the default text for preview warnings it should be calling a getter to get the message not a function that builds the warning. [[User:Awesome Aasim|Awesome]] [[User_talk:Awesome Aasim|Aasim]] 08:41, 1 April 2024 (UTC)

== Template-protected edit request on 29 August 2024 ==

{{edit template-protected|Module:If preview|answered=yes}}
Please implement my changes in the [[Module:If preview/sandbox|sandbox]].

I addressed some of the concerns above, and added a new function <code>warn</code> that calls both mw.addWarning and adds the warning to the preview, as well as <code>consoleWarning</code>. I also added [[Module:Arguments]] for better argument processing, and added a parameter "consolewarning" that would emit a warning in the "script warning" section of the edit window where it is desired. This should ensure backwards compatibility. [[User:Awesome Aasim|Awesome]] [[User_talk:Awesome Aasim|Aasim]] 18:17, 29 August 2024 (UTC)

:Yes please! If using mw.addWarning() is for some reason controversial, the obvious solution is to do that via a separate function (or, I guess, an argument to an existing one). Flipping the default (making mw.addPreview() opt-out would make more sense, but seems more effort than it's worth. on enWP; on enWS where I import it I'd swap it in a heartbeat if I could without creating merge issues for myself). [[User:Xover|Xover]] ([[User talk:Xover|talk]]) 10:49, 1 September 2024 (UTC)
:{{done}}<!-- Template:ETp --> &mdash;&nbsp;Martin <small>([[User:MSGJ|MSGJ]]&nbsp;·&nbsp;[[User talk:MSGJ|talk]])</small> 19:58, 9 September 2024 (UTC)

== Edit request 15 July 2025 ==

{{Edit template-protected|Module:If preview/styles.css|answered=yes}}

'''Description of suggested change:''' Add support for dark mode.

'''Diff:''' (in [[Module:If preview/styles.css#L-7]]
{{TextDiff|1=	color: red;|2=	color: var(--color-error, red);}} [[User:Dabao qian|Dabao qian]] ([[User talk:Dabao qian|talk]]) 06:31, 15 July 2025 (UTC)
: {{Done}} [[User:Pppery|* Pppery *]] [[User talk:Pppery|<sub style="color:#800000">it has begun...</sub>]] 22:29, 16 July 2025 (UTC)

== Bug if transcluded? ==

Anyone else experience a bug where this module thinks a page is being previewed when the page is actually being transcluded. <span class="fn nickname" style="color:#CD0000">[[User:Waddie96|waddie96]] ★ ([[User talk:Waddie96|talk]])</span> 10:07, 29 September 2025 (UTC)