Wikipedia talk:Lua

WP:Lua (talk) Help To do Resources Reference manual

Looped args with TemplateData template

I'm trying to make a template that helps with TemplateData (basically, makes it a bit less complicated to do and has it in template form. User:Lemondoge/templatedata) Currently it only supports 3 parameters, and I am trying to figure out how to make it support infinitely many parameters. I have an unfinished module page for it (Module:Sandbox/Lemondoge/templatedata), but I can't figure out how to make it work - already stuck on how to concatenate arguments to create JSON format. Any help? (See template page and documentation for information on the usage of the template in its current state.) {​{Lemondoge|Talk|Contributions}} 19:45, 2 December 2019 (UTC)

First, in the template, enumerate parameters with digits not with text; if you don't, parameter names will get really ugly really fast. Do not mix positional parameters with named parameters; that will simply cause you headaches and confusion down the road so: |label1=, |param1=, |description1=, |type1=, |status1=; then |label2=, ... etc.

You can create a loop that calls a function by doing something like:

require('Module:No globals');
local getArgs = require ('Module:Arguments').getArgs;

local function function_that_does_stuff (label, param, description, ptype, status)
	local result
	-- wherein stuff gets done that sets result
	return result
end

local function templatedata (frame)
	local args=getArgs (frame)
	local final_result
	
	local i=1

	while frame.args['label'..i] do
		local result = function_that_does_stuff (args['label'..i], args['param'..i], args['description'..i], args['type'..i], args['status'..i])
		-- here do something with result to fill final_result
		i = i + 1;
		
	end
	
	-- here do something to finish off final_result
	
	return final_result
end

return templatedata

caveat lector: the above is just hacked from the top of my head; not tested, probably has bugs, but should serve as a starting place.

—Trappist the monk (talk) 20:19, 2 December 2019 (UTC)

As far as what I'm doing goes, this does not seem to function properly. If I leave this unmodified for debug and just invoke the function, it gives this: "Script error: The module returned a function value. It is supposed to return an export table." Otherwise, final_result seems to just not be written to at all - unless I just define it as a string (e.g. local final_result = "poof"), the template will do nothing, regardless of parameters. Current code is:

require('Module:No globals');
local getArgs = require ('Module:Arguments').getArgs;
local p = {}
local function function_that_does_stuff (label, param, description, ptype, status)
	local result
	result = '"'..param..'": { "label": '..label..'", "description": "'..description..'", "type": "'..ptype..'", "required": '..status..' },'
	return result.."poof"
end

function p.templatedata (frame)
	local args=getArgs (frame)
	local final_result
	local i=1

	while frame.args['label'..i] do
		local result = function_that_does_stuff (args['label'..i], args['param'..i], args['description'..i], args['type'..i], args['status'..i])
		final_result = final_result..result
		i = i + 1;
		
	end
	
	return final_result
end

return p

{​{Lemondoge|Talk|Contributions}} 22:54, 2 December 2019 (UTC)

Update: hold up it gives you a sort of VisualEditor thingamajig for doing TemplateData on the top-left of a template documentation page when you're editing it - apparently this template thing is basically just pre-deprecated and useless. abort mission {​{Lemondoge|Talk|Contributions}} 23:10, 2 December 2019 (UTC)

Again looped args

Hi, I just continue with Lemondoges request - which does not bear an answer to my problem:

1. a template gets an unknown, possibly large amount of parameters. For each parameter the same action is required (it does not matter whether there are single parameters, pairs or other tupels, and when there are named global parameters in addition).
2. The parameters are passed to a Lua module, which analizes them, and performs a loop through the parameter list.
3. For each action the parameter (or parameters) must be passed to kind of layout template which performs the action, whatever it may be.

But at the moment I am not able to perform a repetitive frame:expandTemplate{ title = title, args = } where the argument[s] are one after the other the values from a loop; Lua seems to allow only one frame:expandTemplate{} as the only one return value? When that is the concept of Lua, this restriction should be expanded, because there are numerous templates having problems with long parameter lists! Poor code constructions like {{#if:{{{1|}}}|... until e.g. {{#if:{{{33|}}}|... will fail as soon as there are 34 parameters to handle. A loop in Lua can serve any uncountable number of parameters, when the repetitive transclusion is possible. sarang♥사랑 16:40, 14 January 2020 (UTC)

If your parameters are all positional {{{1}}} ... {{{n}}} then you might write something like this (untested and presuming that you have extracted an args table from the appropriate frame):

local out = {}
for i, v in ipairs (args) do
  table.insert (out, frame:expandTemplate{ title = title, args = v })
end
return table.concat (out)

Each time through the loop you get the next enumerated parameter value, call the template on that value, insert the result in the output table. When done looping, concatenate all of the template outputs into a big-damn-string and return that big-damn-string.

A sandbox showing what you have done so far, almost never goes amiss when asking for help.

—Trappist the monk (talk) 16:56, 14 January 2020 (UTC)

@Trappist the monk: thank you very much, your solution works! I never got that idea, but now I am happy that I can solve lots of problems. sarang♥사랑 12:26, 16 January 2020 (UTC)

System variables

Another thing I cannot find information about: sure there must be an access to the system variables (of course it can be passed by a template, but how con I get it directly by the Lua code); how can I get e.g. environment parameters like the {{PAGENAME}} where the code is executed? sarang♥사랑 12:25, 19 January 2020 (UTC)

Does mw.title.getCurrentTitle().text do what you want? If you are looking for the name of the module then frame:getTitle(). Have you looked in mw:Extension:Scribunto/Lua reference manual?

—Trappist the monk (talk) 13:14, 19 January 2020 (UTC)

Yes, it is; thank you. I checked through the reference but I could not understand that that is what I needed. sarang♥사랑 06:29, 21 January 2020 (UTC)

Improvement to Module:Trim quotes to distinguish single/double quoting from bold and italics wikimarkup

Please see Template talk:Trim quotes#Wikimarkup interference. Trying to get Lua to do this gives me a headache, though I could do it easily in bash or Perl or whatnot. Lua just hasn't sunk in yet.  — SMcCandlish ☏ ¢ 😼  21:35, 30 January 2020 (UTC)

Module:Is_stub

I just created Module:Is_stub for merging {{uncategorized stub}}. It detects if a page is tagged with a stub tag or not with a very high accuracy. Could someone please tell me either point me to the existing template for this purpose or tell me why this is a bad idea. I won't believe that this is the first time someone have thought of this. ‑‑Trialpears (talk) 21:54, 30 January 2020 (UTC)

Redundant to Module:Page and Module:String. {{#if:{{#invoke:String|match|{{#invoke:Page|getContent|{{FULLPAGENAME}}|as=raw}}|stub|ignore_errors=1}}|yes|no}} does the exact same thing without creating more module bloat. * Pppery * _{it has begun...} 00:17, 31 January 2020 (UTC)

Thanks, I turned it into {{Stub other}}. ‑‑Trialpears (talk) 09:48, 4 February 2020 (UTC)

Discussion at Wikipedia:Templates for discussion/Log/2020 February 13#Module:HelloWorld

 You are invited to join the discussion at Wikipedia:Templates for discussion/Log/2020 February 13#Module:HelloWorld. * Pppery * _{it has begun...} 22:28, 13 February 2020 (UTC)Template:Z48

Discussion at Wikipedia:Help_desk#Why_do_so_many_commonly-used_templates_use_MODULES?_When_they_don't_need_to?

 You are invited to join the discussion at Wikipedia:Help_desk#Why_do_so_many_commonly-used_templates_use_MODULES?_When_they_don't_need_to?. * Pppery * _{it has begun...} 01:15, 15 February 2020 (UTC)Template:Z48

Connecting Wikipedia articles to reliable sources through new template

Hi All,

Please have a look at my proposal and contribute with your opinions: Wikipedia:Village_pump_(proposals)#Connecting_Wikipedia_articles_to_reliable_sources_through_new_template

Thanks, Adam Harangozó (talk) 14:14, 23 February 2020 (UTC)

Get all pages in a category

Hi! Is there a way to get the list of pages in a category within a Lua module? I checked the Lua reference manual carefully, thought about it and tried a few things, but no luck, so before giving up I thought about asking here. Thanks! Sophivorus (talk) 19:15, 23 March 2020 (UTC)

We've discussed this a few times and believe it to be impossible. You can display the list of members on a page in a way visible to the reader, but there is no way for Lua to read its contents back. Certes (talk) 19:33, 23 March 2020 (UTC)

It would be possible if mw:Extension:CategoryToolbox would be enabled on this wiki. --Gonnym (talk) 11:08, 24 March 2020 (UTC)

Actually looking at it now, the doc doesn't show it has an option to get all pages in category, but to check if a page is in a category, so nevermind. --Gonnym (talk) 11:10, 24 March 2020 (UTC)

Tracked in Phabricator
Task T138229

The real fix for this and other similar problems is allow lua to fetch the content of strip markers. It used to be, for example, that it was possible to get the content of <math>...</math> tags from the math strip marker using mw.text.unstripNoWiki(). That was, and still is important to me because the content of <math>...</math> tags is rendered as images. cs1|2 creates metadata for use by Zotero and other reference management software. But, the metadata doesn't accept the transient images that mediawiki uses to render the equation. For the metadata, cs1|2 used to get the content of the math strip marker and extracted the original source equation from the <math>...</math> tags for use in the metadata. But, mediawiki took away that ability so now, metadata for article titles with equations use MATH RENDER ERROR text in place of the equation (better that than as percent encoded version of the strip marker).

—Trappist the monk (talk) 12:21, 24 March 2020 (UTC)

Script to fetch the nutshell text of a given page

Per this discussion at the VPT (start reading at "related idea"), we'd like to have a module that can take as input a given page and return the text from the {{Nutshell}} on that page if one exists (and return "null" or something if the page doesn't have a nutshell). Would that be possible to create without too much effort? {{u|Sdkb}} ^talk 21:14, 4 April 2020 (UTC)

Scripts and lua are not the same thing. At least I don't see them as the same thing. A script runs on your browser. Lua runs when MediaWiki compiles wikitext into the html that your browser displays as an article. If you are looking for a script, then this place is not the right place to be looking.

If you are looking to create shortcut templates that have tooltips where the text of the tooltip is taken from a {{nutshell}} template in the target page, I think that can be done. But shortcuts often link to sections that don't have {{nutshell}} and for for those that do the search has to be constrained to that section and you have to look for {{nutshell}} and all of its redirects:

{{Essay in a nutshell}}

{{Guideline in a nutshell}}

{{Guideline one liner}}

{{In a nutshell}}

{{Inanutshell}}

{{Naming convention in a nutshell}}

{{Nutshell2}}

{{Policy in a nutshell}}

{{Policy proposal in a nutshell}}

{{Proposal in a nutshell}}

—Trappist the monk (talk) 21:41, 4 April 2020 (UTC)

See Template:Template parameter value * Pppery * _{it has begun...} 21:43, 4 April 2020 (UTC)

Something else to consider, wiki markup in a nutshell template. For example, this is the parameter value at WP:EP

Improve pages wherever you can, and do not worry about leaving them imperfect. Preserve the value that others add, even if they "did it wrong" (try to fix it rather than [[WP:Deletion policy|delete it]]).

Converting that to a titletip:

[[WP:EP|<span title="Improve pages wherever you can, and do not worry about leaving them imperfect. Preserve the value that others add, even if they 'did it wrong' (try to fix it rather than [[WP:Deletion policy|delete it]]).">WP:EP</span>]]

WP:EP

For the purposes of example, I manually changed the double quotes within the nutshell text to single quotes within the span; those kinds of things will also need to be handled.

—Trappist the monk (talk) 22:59, 4 April 2020 (UTC)

@Sdkb and Trappist the monk: I've started this module. See Module:Nutshell, and User:Guywan/Test2, where it is used. Needs some work yet, I'm no Lua expert. —guywan (talk • contribs) 14:49, 5 April 2020 (UTC)

We always seem to forget that whitespace around template names is allowed. Here is a table of {{nutshell}} redirect patterns with whitespace; works well with ipairs():

local redirects_nutshell_patterns = {
	'{{%s*[Nn]utshell%s*|',
	'{{%s*[Ee]ssay in a nutshell%s*|',
	'{{%s*[Gg]uideline in a nutshell%s*|',
	'{{%s*[Gg]uideline one liner%s*|',
	'{{%s*[Ii]n a nutshell%s*|',
	'{{%s*[Ii]nanutshell%s*|',
	'{{%s*[Nn]aming convention in a nutshell%s*|',
	'{{%s*[Nn]utshell2%s*|',
	'{{%s*[Pp]olicy in a nutshell%s*|',
	'{{%s*[Pp]olicy proposal in a nutshell%s*|',
	'{{%s*[Pp]roposal in a nutshell%s*|',
	}

I recently wrote a function to strip all wikilinks from a template. You might find this useful because who knows how many wikilinks will appear in nutshell text:

local function wikilink_strip (template)
	for wikilink in template:gmatch ('%[%b[]%]') do								-- get a wikilink
		if wikilink then
			template = template:gsub ('%[%b[]%]', '__57r1P__', 1);				-- install a marker
			if wikilink:match ('%[%[.-|(.-)%]%]') then
				wikilink = wikilink:match ('%[%[.-|(.-)%]%]');					-- extract label from complex [[link|label]] wikilink
			else
				wikilink = wikilink:match ('%[%[(.-)%]%]');						-- extract link from simple [[link]] wikilinks
			end
			wikilink = escape_lua_magic_chars (wikilink);						-- in case there are lua magic characters in wikilink
			template = template:gsub ('__57r1P__', wikilink, 1);				-- replace the marker with the appropriate text
		end
	end

	return template;
end

The if wikilink then may not be necessary. I think it is a left-over artifact from an earlier version of the code that did not work.

The above doesn't answer the what to do about templates found in a nutshell template (preprocess them, I suppose). What to do about html? I don't think that bullet points are supported in tooltips so string them all together? What about prefixing? Use the default title text or the default title text modified by |title=? Ignore?

Consider using find() to find a particular nutshell pattern then, with the start position returned from find(), use match ('%b{}', start) to get the whole template.

Is it really necessary to use the ustring functions?

Find a better module name. Module:Nutshell implies that it is used to implement all or part of {{nutshell}}; it is not.

—Trappist the monk (talk) 15:42, 5 April 2020 (UTC)

@Trappist the monk: Thanks for your suggestions. I'd say strip anything that isn't sentence-like.

Find a better module name. I'm not passionate about the name. You are welcome to give it another one.

Is it really necessary to use the ustring functions? Not anymore :)

escape_lua_magic_chars() Where is this defined, and how important is it?

Regards, —guywan (talk • contribs) 22:19, 5 April 2020 (UTC)

Here:

--[[--------------------------< E S C A P E _ L U A _ M A G I C _ C H A R S >----------------------------------

Returns a string where all of lua's magic characters have been escaped.  This is important because functions like
string.gsub() treat their pattern and replace strings as patterns, not literal strings.

]]

local function escape_lua_magic_chars (argument)
	argument = argument:gsub("%%", "%%%%");										-- replace % with %%
	argument = argument:gsub("([%^%$%(%)%.%[%]%*%+%-%?])", "%%%1");				-- replace all other lua magic pattern characters
	return argument;
end

If I can remember, I think that I added this to wikilink_strip() because something that was being stripped had a percent-encoded space (%20) in it that caused lua to choke because it saw that as a capture reference that it had not captured. You may never encounter that problem. I don't remember why I separated the % escape from the rest of the lua magic characters. I've had no reason to change it because it has been working since I don't remember when.

What do you intend to call User:Guywan/Test2 when it becomes a template? Use that name for this module?

—Trappist the monk (talk) 23:07, 5 April 2020 (UTC)

@Guywan and Trappist the monk: Glad to see progress being made here! I would prefer for the template to be able to be called using {{WP|BOLD}}. But maybe the WP should just be a shortcut and the template itself should be given a better name. Pppery, I'm having some trouble getting {{Template parameter value}} to work correctly. Do you or anyone else know what I'm doing wrong at User:Guywan/Test2? {{u|Sdkb}} ^talk 22:26, 7 April 2020 (UTC)

Template:Template parameter value is a bit finnicky. First, you have to pass the redirect target to it, rather than the redirect itself. Secondly, it cares about the capitalization of {{nutshell}} on the target page. For instance,

{{template parameter value|{{#invoke:Redirect|main|WP:BOLD}}|nutshell|1|1|1|1}}

Go for it. works, but

{{template parameter value|{{#invoke:Redirect|main|WP:BOLD}}|Nutshell|1|1|1|1}}

Go for it. does not. Alex 21 (the author of {{template parameter value}}), what do you think about updating the template to automatically bypass redirects and ignore the case of the first character in the template name? * Pppery * _{it has begun...} 22:41, 7 April 2020 (UTC)

@Guywan, Trappist the monk, Pppery, and Alex 21: Okay, so checking in on where we're at, it looks like we're pretty close, since User:Guywan/Test2 currently works based on Module:Nutshell. The only issue is that, when used for pages without a nutshell, it returns a big error message, rather than just returning a link to the page without a tooltip or dotted underline, as would be preferable. Is there any easy way to get that behavior? Once that's done, I think we'll be ready to move out of userspace and into template space and start using. {{u|Sdkb}} ^talk 02:59, 11 April 2020 (UTC)

I hacked on Module:Nutshell for a bit. I moved the tooltip creation into the module reorganized how the nutshell template is disassembled, added support for multiple positional parameters, and support for extracting a value from |title=.

There is this one:

{{#invoke:WP | main | SIG }} → WP:SIG

In the positional parameter it has [[File:OOUI JS signature icon LTR.svg|22px]] () renders in the tooltip as 22px; what to do about that?

—Trappist the monk (talk) 19:22, 11 April 2020 (UTC)

Code tweaked to replace the image with text: [IMAGE]. I suppose that we could parse apart the image wikilink for alt text or caption. Is it worth it? We might get some text to go in the tooltip but that text might not fit grammatically in the rest of the tooltip.

—Trappist the monk (talk) 19:37, 11 April 2020 (UTC)

@Trappist the monk and Guywan: I've gone ahead and launched the template at Template:WP, since it seems to be working pretty well. For a further improvement (and looking at the code, this may already be in progress), it'd be good to have the page title written out in the tooltip instead of "this page", so that the tooltip for WP:BLP reads Biographies of living persons in a nutshell: Material about... instead of This page in a nutshell: Material about... Once you've made all the improvements you want, lmk and we can announce it at the Community bulletin board. {{u|Sdkb}} ^talk 07:32, 12 April 2020 (UTC)

Here are some questions that I think need answers:

• when the nutshell holds an image, is it worth the effort to parse apart the File: or Image: wikilink to extract alt text or caption text?
• there is code in Module:WP that looks for a stub template and if found, causes an error return. Why do we care if the target page is a stub?
• should this module accept MOS:... or other namespace abbreviations? WP:LIST is a shortcut to a dab page that includes the MOS:LIST target which has a {{nutshell}} template.

—Trappist the monk (talk) 17:25, 12 April 2020 (UTC)

@Trappist the monk: Re image, it seems very rare for an image to be in a nutshell, so I'd say no. The alt text might occasionally work, but it's just as (if not more) likely to be missing or incomplete, which would just add to the confusion. The current solution of "[IMAGE]" at least alerts the reader that there's an image there and that they might just want to click through.

Re stubs, it seems perfectly possible that a stub would have a nutshell, so I don't see why we'd want to exclude them from the template. Maybe figure out the WP:FENCE aspect, but if there's nothing technical making it necessary, just get rid of it.

Re other namespace abbreviations, Template:MOS, unlike Template:WP, is taken, so it'd be hard to allow {{MOS|LEAD}}, but WP:LEAD works fine, and goes to the same place.

And I'm glad to see the page titles now being included! (Thanks for coding that!) I notice that it can get a bit confusing for some, as in WP:BITE seems to be talking about biting newcomers in a nutshell (lol) with the current Wikipedia:Please do not bite the newcomers in a nutshell: Do not be... Adding quotes around the title could fix that. We could also use a period or line break to make it clearer that the link goes to the page. Together with those changes, we'd have something like "Wikipedia:Please do not bite the newcomers". In a nutshell: Do not be... I'm also on the fence about whether to we should take out the "Wikipedia:" — do you think it adds enough to be worth including?

Oh, and one thing showing up in WP:NPOV and a few other test cases is that italics and bolding aren't being reflected. Do Wikipedia tooltips have the technical capability to handle formatting like that? (If so, it might be nice to bold the article title to help it stand out a bit.) {{u|Sdkb}} ^talk 19:45, 12 April 2020 (UTC)

I concur that image alt text or caption text would be problematic in that, when it exists, and the likely hood of that happening is rather remote, whatever text is in the image markup won't fit grammatically with the surrounding text.

This search finds no stubs that use {{nutshell}}. Just to prove that the stub search portion of that isn't broken, this search finds about 2500 stub templates. Given these results, I'm going to delete that snippet of code. If it turns out that there is a reason for it being there, the code is in the history of the module so it can be dredged up and restored.

I was thinking more along the lines of accepting a MOS: prefixed argument ({{WP|MOS:LEAD}}) that would render as MOS:LEAD (with the tool tip and dotted underlining). It is my understanding that MOS shortcuts are preferred for the manual of style. Maybe I'll hack something into this code to see how that would work.

I've added quotes around the article title. I have not added the full stop. You did, showing it outside the quotes. That is one of the grammatical things I almost always get wrong so I don't know if the dot goes inside or outside. So I've left it off until someone confirms your usage. I've been thinking that the 'Wikipedia:' prefix should be shortened to 'WP:' in keeping with the template name: "WP:Please do not bite the newcomers" in a nutshell: Do not be....

Italic and bold markup will not work. To prove that, I did an experiment. I added <b>...</b> around the article title portion of the tooltip. Not surprisingly, html tags inside a title attribute inside a <span> confused MediaWiki so the enclosing <span>...</span> rendered as linked plain text (but the title was bold). Right now, we do nothing with the bold and italic markup so where it exists in the {{nutshell}} text, it shows up as raw markup in the tooltip. Leave it because we all know what it means, or strip it?

—Trappist the monk (talk) 22:43, 12 April 2020 (UTC)

My experience elsewhere is that image handling can make a simple module very complex. Images hidden in infoboxes with unusual parameter names, non-free images with rationales for the source but not the destination, complex wikitext within captions and other gotchas can take more coding and CPU time than the module's actual purpose. Avoid if possible. Certes (talk) 22:55, 12 April 2020 (UTC)

Stub code gone.

MOS: prefixed shortcuts:

{{WP|MOS:LEAD}} → MOS:LEAD same as {{WP|WP:LEAD}} → WP:LEAD and {{WP|LEAD}} → WP:LEAD

{{WP|MOS:TM}} → MOS:TM not the same as {{WP|WP:TM}} → WP:TM and {{WP|TM}} → WP:TM

{{WP|MOS:MED}} → MOS:MED not the same as {{WP|WP:MED}} → WP:MED ?? {{WP|MED}} → WP:MED

This facility might also be expanded to the Help namespace.

—Trappist the monk (talk) 00:20, 13 April 2020 (UTC)

@Trappist the monk: Regarding the full stop, it saddens me to report this, since I'm very much #TeamInside, but per the MOS, Wikipedia style is to have it outside. And I agree that WP would be good — it's shorter than writing out Wikipedia while making it clearer that the thing in quotes is a page title than leaving it out. {{u|Sdkb}} ^talk 00:39, 13 April 2020 (UTC)

Support added for Help namespace and Wikipedia namespace alias Project:

{{WP|Help:CS1}} → Help:CS1

{{WP|Project:LEAD}} → Project:LEAD

Namespaces and namespace aliases are case insensitive but pseudo namespaces are treated like article names so only the first character is case insensitive. The supported pseudo namespaces are H and MOS:

{{WP|h:CS1}} → Help:CS1

{{WP|mOS:MED}} → MOS:MED

but

{{WP|mos:MED}} → MOS:MED

—Trappist the monk (talk) 15:01, 13 April 2020 (UTC)

@Trappist the monk: I've made some minor changes, mostly to the main function. I unified namespaces and pseudo_namespaces so we only have to lookup in one table. Namespace input like h, H, pRoJeCt, and mOs are 'normalised' to Help, Project, and MOS. —guywan (talk • contribs) 14:27, 14 April 2020 (UTC)