Module:Cat main

This Lua module is used on approximately 200,000 pages.
To avoid major disruption and server load, any changes should be tested in the module's /sandbox or /testcases subpages, or in your own module sandbox. The tested changes can be added to this page in a single edit. Consider discussing changes on the talk page before implementing them.

This module produces hatnote saying "The main article for this category is x." It implements the {{cat main}} template.

Use from wikitext

This module should usually be used via the {{cat main}} template. However, it can also be used from #invoke with the syntax {{#invoke:Cat main|catMain|parameters}}. Please see the {{cat main}} template documentation for available parameters.

Use from other Lua modules

Load the module:

local mCatMain = require('Module:Cat main')

You can then use the _catMain function like this:

mCatMain._catMain(options, ...)

options is an optional table that can be used to configure the function's output. There are two available options, "article" and "selfref".

article - if this is set to false, "no", "n", "false", or 0, the module outputs "The main page" rather than "The main article". Use the code {article = false}.
selfref - this is used when the output is a self-reference to Wikipedia. To set this option, use {selfref = true}. (See the {{selfref}} template for more details on self-references.)

The remaining arguments are page names to be turned into link(s) following the text "The main article for this category is". If no page names are specified, the current page name (minus the namespace name) is used for the first link.

Example 1

mCatMain._catMain(nil, 'Foo')

Produces:

<div class="hatnote relarticle mainarticle">The main article for this [[Help:Categories|category]] is '''[[Foo]]'''.</div>

Displays as:

Example 2

mCatMain._catMain(nil, 'Foo', 'Bar', 'Baz')

Produces:

<div class="hatnote relarticle mainarticle">The main articles for this [[Help:Categories|category]] are '''[[Foo]]''', '''[[Bar]]''' and '''[[Baz]]'''.</div>

Displays as:

Example 3

mCatMain._catMain({article = false}, 'Foo')

Produces:

<div class="hatnote relarticle mainarticle">The main page for this [[Help:Categories|category]] is '''[[Foo]]'''.</div>

Displays as:

Technical details

This module uses Module:Hatnote to format the hatnote text.

-- This module implements {{cat main}}.

local mHatnote = require('Module:Hatnote')
local mFormatLink = require('Module:Format link')
local yesno = require('Module:Yesno')
local mTableTools -- lazily initialise
local mArguments -- lazily initialise

local p = {}

function p.catMain(frame)
	mTableTools = require('Module:TableTools')
	mArguments = require('Module:Arguments')
	local args = mArguments.getArgs(frame, {wrappers = 'Template:Cat main'})
	local pages = mTableTools.compressSparseArray(args)
	local options = {
		article = args.article,
		selfref = args.selfref
	}
	return p._catMain(options, unpack(pages))
end

function p._catMain(options, ...)
	options = options or {}

	-- Get the links table.
	local links = mFormatLink.formatPages({}, {...})
	if not links[1] then
		local page = mw.title.getCurrentTitle().text
		links[1] = mFormatLink._formatLink{link = page}
	end
	for i, link in ipairs(links) do
		links[i] = string.format("'''%s'''", link)
	end

	-- Get the pagetype.
	local pages = {...}
	local pagetype 
	
	if options.article ~= nil then
		pagetype = yesno(options.article) ~= false and 'article' or 'page'
	elseif pages and pages[1] then
		local page = pages[1]:gsub("|.*","")
		pagetype = mw.title.new(page).namespace == 0 and "article" or "page"
	else
		pagetype = "article"
	end

	-- Work out whether we need to be singular or plural.
	local stringToFormat
	if #links > 1 then
		stringToFormat = 'The main %ss for this [[Help:Categories|category]] are %s.'
	else
		stringToFormat = 'The main %s for this [[Help:Categories|category]] is %s.'
	end

	-- Get the text.
	local text = string.format(
		stringToFormat,
		pagetype,
		mw.text.listToText(links)
	)
	
	-- Pass it through to Module:Hatnote.
	local hnOptions = {}
	hnOptions.selfref = options.selfref

	return mHatnote._hatnote(text, hnOptions)
end

return p