Documentation for this module may be created at વિભાગ:documentation/doc

local export = {}

-- it is either here, or in [[Module:ugly hacks]], and it is not in ugly hacks.
function export.CONTENTMODEL()
	return mw.title.getCurrentTitle().contentModel
end

local skins = {
	["common"     ] = "";
	["vector"     ] = "Vector";
	["monobook"   ] = "Monobook";
	["cologneblue"] = "Cologne Blue";
	["modern"     ] = "Modern";
}

local Array = require "Module:array"

local function compare_pages(page1, page2, text)
	return "[" .. tostring(
		mw.uri.fullUrl("Special:ComparePages", { page1 = page1, page2 = page2 }))
		.. " " .. text .. "]"
end

local function page_exists(title)
	local success, title_obj = pcall(mw.title.new, title)
	return success and title_obj.exists
end

-- Avoid transcluding [[Module:languages/cache]] everywhere.
local lang_cache = setmetatable({}, { __index = function (self, k)
	return require "Module:languages/cache"[k]
end })

local function zh_link(word)
	return require("Module:links").full_link{
		lang = lang_cache.zh,
		term = word
	}
end

local function make_languages_data_documentation(title, cats, division)
	local doc_template, module_cat
	if division:find("/extra$") then
		division = division:gsub("/extra$", "")
		doc_template = "language extradata documentation"
		module_cat = "Language extra data modules"
	else
		doc_template = "language data documentation"
		module_cat = "Language data modules"
	end
	local sort_key
	if division == "exceptional" then
		sort_key = "x"
	else
		sort_key = division:gsub("/", "")
	end
	cats:insert(module_cat .. "|" .. sort_key)
	return mw.getCurrentFrame():expandTemplate {
		title = doc_template
	}
end

local function make_Unicode_data_documentation(title, cats)
	local subpage, first_three_of_code_point
		= title.fullText:match("^Module:Unicode data/([^/]+)/(%x%x%x)$")
	if subpage == "names" or subpage == "images" then
		local low, high =
			tonumber(first_three_of_code_point .. "000", 16),
			tonumber(first_three_of_code_point .. "FFF", 16)
		return string.format(
			"This data module contains the %s of " ..
			"[[Appendix:Unicode|Unicode]] code points within the range U+%04X to U+%04X.",
			subpage == "images" and "titles of images" or "names",
			low, high)
	end
end

-- This provides categories and documentation for various data modules, so that
-- [[Category:Uncategorized modules]] isn’t unnecessarily cluttered.
-- It is a list of tables, each of which have the following possible fields:

-- `regex` (required): A Lua pattern to match the module's title. If it matches, the data in this entry will be used.
-- Any captures in the pattern can by referenced in the `cat` field using %1 for the first capture, %2 for the
-- second, etc. (often used for creating the sortkey for the category). In addition, the captures are passed to the
-- `process` function as the third and subsequent parameters.

-- `process` (optional): This may be a function or a string. If it is a function, it is called as follows:
--    process(TITLE, CATS, CAPTURE1, CAPTURE2, ...)
-- where:
--    * TITLE is a title object describing the module's title; see [https://www.mediawiki.org/wiki/Extension:Scribunto/Lua_reference_manual#Title_objects].
--    * CATS is an array object (see [[Module:array]]) of categories that the module will be added to.
--    * CAPTURE1, CAPTURE2, ... contain any captures in the `regex` field.
-- The return value of `process` should be a string and will be used as the module's documentation.
-- If `process` is a string, it is the name of a submodule under 'Module:documentation/functions/' which returns a
-- function, of the same type as described above. If `process` is omitted entirely, the module will have no
-- documentation.

-- `cat` (optional): A string naming the category into which the module should be placed. Captures specified in `regex`
-- may be referenced in this string using %1 for the first capture, %2 for the second, etc. Currently, in order to put
-- the module into multiple categories, you need to write a `process` function that adds categories to the CATS
-- parameter passed in.
local module_regex = {
	{
		regex = "^Module:languages/data/(3/./extra)$",
		process = make_languages_data_documentation,
	},
	{
		regex = "^Module:languages/data/(3/.)$",
		process = make_languages_data_documentation,
	},
	{
		regex = "^Module:languages/data/(2/extra)$",
		process = make_languages_data_documentation,
	},
	{
		regex = "^Module:languages/data/(2)$",
		process = make_languages_data_documentation,
	},
	{
		regex = "^Module:languages/data/(exceptional/extra)$",
		process = make_languages_data_documentation,
	},
	{
		regex = "^Module:languages/data/(exceptional)$",
		process = make_languages_data_documentation,
	},
	{
		regex = "^Module:languages/.+$",
		cat = "Language and script modules",
	},
	{
		regex = "^Module:scripts/.+$",
		cat = "Language and script modules",
	},
	{
		regex = "^Module:data tables/data..?.?.?$",
		cat = "Reference module sharded data tables",
	},
	{
		regex = "^Module:zh/data/dial%-pron/.+$",
		cat = "Chinese dialectal pronunciation data modules",
		process = "zh dial or syn",
	},
	{
		regex = "^Module:zh/data/dial%-syn/.+$",
		cat = "Chinese dialectal synonyms data modules",
		process = "zh dial or syn",
	},
	{
		regex = "^Module:zh/data/glyph%-data/.+$",
		cat = "Chinese historical character forms data modules",
		process = function(title, cats)
			local character = title.fullText:match("^Module:zh/data/glyph%-data/(.+)")
			if character then
				return ("This module contains data on historical forms of the Chinese character %s.")
					:format(zh_link(character))
			end
		end,
	},
	{
		regex = "^Module:zh/data/ltc%-pron/(.+)$",
		cat = "Middle Chinese pronunciation data modules|%1",
		process = "zh data",
	},
	{
		regex = "^Module:zh/data/och%-pron%-BS/(.+)$",
		cat = "Old Chinese (Baxter-Sagart) pronunciation data modules|%1",
		process = "zh data",
	},
	{
		regex = "^Module:zh/data/och%-pron%-ZS/(.+)$",
		cat = "Old Chinese (Zhengzhang) pronunciation data modules|%1",
		process = "zh data",
	},
	{
		-- capture rest of zh/data submodules
		regex = "^Module:zh/data/(.+)$",
		cat = "Chinese data modules|%1",
	},
	{
		regex = "^Module:mul/guoxue%-data/cjk%-?(.*)$",
		process = "guoxue-data",
	},
	{
		regex = "^Module:Unicode data/(.+)$",
		cat = "Unicode data modules|%1",
		process = make_Unicode_data_documentation,
	},
	{
		regex = "^Module:number list/data/(.+)$",
		process = "number list",
	},
	{
		regex = "^Module:accel/(.+)$",
		process = function(title, cats)
			local lang_code = title.subpageText
			local lang = lang_cache[lang_code]
			if lang then
				cats:insert(lang:getCanonicalName() .. " modules|accel")
				cats:insert(("Accel submodules|%s"):format(lang:getCanonicalName()))
				return ("This module contains new entry creation rules for %s; see [[WT:ACCEL]] for an overview, and [[Module:accel]] for information on creating new rules.")
					:format(lang:makeCategoryLink())
			end
		end,
	},
	{
		regex = "^Module:inc%-ash/dial/data/(.+)$",
		cat = "Ashokan Prakrit modules|%1",
		process = function(title, cats)
			local word = title.fullText:match("^Module:inc%-ash/dial/data/(.+)$")
			if word then
				local lang = lang_cache["inc-ash"]
				return ("This module contains data on the pronunciation of %s in dialects of %s.")
					:format(require("Module:links").full_link({ term = word, lang = lang }, "term"),
						lang:makeCategoryLink())
			end
		end,
	},
	{
		regex = "^Module:[%l-]+:Dialects$",
		process = function(title, cats)
			local content = title:getContent()
			local has_aliases = content:find("aliases") ~= nil
			return mw.getCurrentFrame():expandTemplate {
				title = "dialectal data module",
				args = { ["labels-aliases"] = has_aliases },
			}
		end,
	},
	{
		regex = "^.+%-translit$",
		process = "translit",
	},
	{
		regex = "^Module:form of/lang%-data/(.+)$",
		process = function(title, cats, lang_code)
			local lang = lang_cache[lang_code]
			if lang then
				local langname = lang:getCanonicalName()
				cats:insert("Language-specific form-of modules|" .. lang_code)
				cats:insert(langname .. " modules")
				cats:insert(langname .. " data modules")
				-- FIXME, display more info.
				return "This module contains language-specific form-of data (tags, shortcuts, base lemma params. etc.) for " ..
					langname .. ".\n\n'''NOTE:''' If you add a new language-specific module, you must add the language code to the " ..
					"list at the top of [[Module:form of]] in order for the module to be recognized."
			end
		end
	},
	{
		regex = "^Module:labels/data/lang/(.+)$",
		process = function(title, cats, lang_code)
			local lang = lang_cache[lang_code]
			if lang then
				local langname = lang:getCanonicalName()
				cats:insert("Language-specific label data modules|" .. lang_code)
				cats:insert(langname .. " modules")
				cats:insert(langname .. " data modules")
				return mw.getCurrentFrame():expandTemplate {
					title = "label language-specific data documentation",
					args = { [1] = lang_code },
				}
			end
		end
	},
	{
		regex = "^Module:category tree/poscatboiler/data/lang%-specific/(.+)$",
		process = function(title, cats, lang_code)
			local lang = lang_cache[lang_code]
			if lang then
				local langname = lang:getCanonicalName()
				cats:insert("Category tree data modules/poscatboiler|" .. langname)
				cats:insert(langname .. " modules")
				cats:insert(langname .. " data modules")
				return "This module handles generating the descriptions and categorization for " .. langname .. " category pages "
					.. "of the format \"" .. langname .. " LABEL\" where LABEL can be any text. Examples are "
					.. "[[:Category:Bulgarian conjugation 2.1 verbs]] and [[:Category:Russian velar-stem neuter-form nouns]]. "
					.. "This module is part of the poscatboiler system, which is a general framework for generating the "
					.. "descriptions and categorization of category pages.\n\n"
					.. "For more information, see [[Module:category tree/poscatboiler/data/lang-specific/documentation]].\n\n"
					.. "'''NOTE:''' If you add a new language-specific module, you must add the language code to the "
					.. "list at the top of [[Module:category tree/poscatboiler/data/lang-specific]] in order for the module to be "
					.. "recognized."
			end
		end
	},
	{
		regex = "^Module:category tree/poscatboiler/data/(.+)$",
		process = function(title, cats, lang_code)
			cats:insert("Category tree data modules/poscatboiler| ")
			return mw.getCurrentFrame():expandTemplate {
				title = "poscatboiler data submodule documentation"
			}
		end
	},
	{
		regex = "^Module:category tree/topic cat/data/(.+)$",
		process = function(title, cats, lang_code)
			return mw.getCurrentFrame():expandTemplate {
				title = "topic cat data submodule documentation"
			}
		end
	},
	{
		regex = "^Module:ja/data/(.+)$",
		cat = "Japanese data modules|%1",
	},
	{
		regex = "^Module:Swadesh/data/(.+)$",
		cat = "Swadesh modules|%1",
	},
	{
		regex = "^Module:typing%-aids",
		process = function(title, cats)
			local data_suffix = title.fullText:match("^Module:typing%-aids/data/(.+)$")
			if data_suffix then
				cats:insert("Data modules")
				if data_suffix:find "^[%l-]+$" then
					local lang = require "Module:languages".getByCode(data_suffix)
					if lang then
						cats:insert(lang:getCanonicalName() .. " modules")
					end
				elseif data_suffix:find "^%u%l%l%l$" then
					local script = require "Module:scripts".getByCode(data_suffix)
					if script then
						cats:insert(script:getCategoryName())
					end
				end
			end
		end,
	},
	{
		regex = "^Module:R:([a-z%-]+):(.+)$",
		process = function(title, cats, lang_code, refname)
			local lang = lang_cache[lang_code]
			if lang then
				cats:insert(lang:getCanonicalName() .. " modules|" .. refname)
				cats:insert(("Reference modules|%s"):format(lang:getCanonicalName()))
				return mw.getCurrentFrame():preprocess("This module implements the reference template {{temp|R:" ..
					lang_code .. ":" .. refname .. "}}.")
			end
		end,
	},
	{
		regex = "^Module:Quotations/([a-z-]+)/?(.*)",
		process = "Quotation",
	},
	{
		regex = "^Module:affix/lang%-data/([a-z-]+)",
		process = "affix lang-data",
	}
}

function export.show(frame)
	local params = {
		["hr"] = {},
		["for"] = {},
		["from"] = {},
		["notsubpage"] = { type = "boolean", default = false },
		["nodoc"] = { type = "boolean", default = false },
	}
	
	local args = require("Module:parameters").process(frame.args, params)
	
	local output = Array('\n<div class="documentation" style="display:block; clear:both">\n')
	local cats = Array()
	
	local nodoc = args.nodoc
	
	if (not args.hr) or (args.hr == "above") then
		output:insert("----\n")
	end
	
	local title = ((args['for'] ~= "") and args['for']) and mw.title.new(args['for'])
		or mw.title.getCurrentTitle()
	local doc_title = mw.title.new((args['from'] ~= "") and args['from']
		or (title.fullText .. '/documentation'))
	local contentModel = title.contentModel
	
	local pagetype = mw.getContentLanguage():lcfirst(title.nsText) .. " page"
	local preload, fallback_docs, doc_content, doc_content_module,
		old_doc_title, user_name, skin_name, needs_doc
	
	if contentModel == "javascript" then
		pagetype = "script"
		if title.nsText == 'MediaWiki' then
			if title.text:find('Gadget-') then
				preload = 'Template:documentation/preloadGadget'
			else
				preload = 'Template:documentation/preloadMediaWikiJavaScript'
			end
		else
			preload  = 'Template:documentation/preloadTemplate' -- XXX
		end
		if title.nsText == 'User' then
			user_name = title.rootText
		end
	elseif contentModel == "css" then
		pagetype = "style sheet"
		preload  = 'Template:documentation/preloadTemplate' -- XXX
		if title.nsText == 'User' then
			user_name = title.rootText
		end
	elseif contentModel == "Scribunto" then
		pagetype = "module"
		user_name = title.rootText:match("^[Uu]ser:(.+)")
		if user_name then
			preload  = 'Template:documentation/preloadModuleSandbox'
		else
			preload  = 'Template:documentation/preloadModule'
		end
	elseif title.nsText == "Template" then
		pagetype = "template"
		preload  = 'Template:documentation/preloadTemplate'
	elseif title.nsText == "Wiktionary" then
		pagetype = "project page"
		preload  = 'Template:documentation/preloadTemplate' -- XXX
	end
	
	if doc_title.isRedirect then
		old_doc_title = doc_title
		doc_title = mw.title.new(string.match(doc_title:getContent(),
			"^#[Rr][Ee][Dd][Ii][Rr][Ee][Cc][Tt]%s*:?%s*%[%[([^%[%]]-)%]%]"))
	end

	output:insert("<dl class=\"plainlinks\" style=\"font-size: smaller;\">")
	if doc_title.exists then
		output:insert(
			"<dd><i style=\"font-size: larger;\">The following " ..
			"[[Help:Documenting templates and modules|documentation]] is located at [[" ..
			doc_title.fullText .. "]]. " ..
			"<sup>[[" .. doc_title:fullUrl { action = 'edit' } .. " edit]]</sup> </i></dd>")
	else
		if contentModel == "Scribunto" then
			local automatic_cats = nil
			if user_name then
				fallback_docs = "documentation/fallback/user module"
				automatic_cats = {"User sandbox modules"}
			else
				for _, data in ipairs(module_regex) do
			        local captures = {mw.ustring.match(title.fullText, data.regex)}
			        if #captures > 0 then
						local cat
						local process_function
						if type(data.process) == "function" then
							process_function = data.process
						elseif type(data.process) == "string" then
							doc_content_module = "Module:documentation/functions/" .. data.process
							process_function = require(doc_content_module)
						end
						
						if process_function then
							doc_content = process_function(title, cats, unpack(captures))
						end
						cat = data.cat
						
						if cat then
							if type(cat) == "string" then
								cat = {cat}
							end
							for _, c in ipairs(cat) do
								-- gsub() and Lua :gsub() return two arguments, which causes all sorts of problems.
								-- Terrible design, there should have been a separate two-argument function.
								local gsub_sucks = mw.ustring.gsub(title.fullText, data.regex, c)
								table.insert(cats, gsub_sucks)
							end
						end
						break
					end
				end
			end

			if not automatic_cats then
				local success, auto_cats =
					pcall(require("Module:module categorization").categorize, frame, true)
				if success then
					for _, category in ipairs(auto_cats) do
						cats:insert(category)
					end
				end
			end

			if title.subpageText == "templates" then
				cats:insert("Template interface modules")
			end

			if automatic_cats then
				for _, c in ipairs(automatic_cats) do
					cats:insert(c)
				end
			end
			
			-- meaning module is not in user’s sandbox or one of many datamodule boring series
			needs_doc = not (automatic_cats or doc_content or fallback_docs)
		elseif title.nsText == "Template" then
			--cats:insert("Uncategorized templates")
			needs_doc = not (fallback_docs or nodoc)
		elseif (contentModel == "css") or (contentModel == "javascript") then
			if user_name then
				skin_name = skins[title.text:sub(#title.rootText + 1):match("^/([a-z]+)%.[jc]ss?$")]
				if skin_name then
					fallback_docs = 'documentation/fallback/user ' .. contentModel
				end
			end
		end
		
		if doc_content then
			local generating_module = doc_content_module or "Module:documentation"
			output:insert(
				"<dd><i style=\"font-size: larger;\">The following " ..
				"[[Help:Documenting templates and modules|documentation]] is " ..
				"generated by [[" .. generating_module .. "]]. <sup>[[" ..
				mw.title.new(generating_module):fullUrl { action = 'edit' } ..
				" edit]]</sup> </i></dd>")
		elseif not nodoc then
			output:insert(
				"<dd><i style=\"font-size: larger;\">This " .. pagetype ..
				" lacks a [[Help:Documenting templates and modules|documentation subpage]]. " ..
				(fallback_docs and "You may " or "Please ") ..
				"[" .. doc_title:fullUrl { action = 'edit', preload = preload }
				.. " create it].</i></dd>\n")
		end
	end
	
	if title.fullText:match("^MediaWiki:Gadget%-") then
		local is_gadget = false
		local gadget_list = mw.title.new("MediaWiki:Gadgets-definition"):getContent()
		
		for line in mw.text.gsplit(gadget_list, "\n") do
			local gadget, opts, items = line:match("^%*%s*([A-Za-z][A-Za-z0-9_%-]*)%[(.-)%]|(.+)$") -- opts is unused
			if not gadget then
				gadget, items = line:match("^%*%s*([A-Za-z][A-Za-z0-9_%-]*)|(.+)$")
			end
			
			if gadget then
				items = Array(mw.text.split(items, "|"))
				for i, item in ipairs(items) do
					if title.fullText == ("MediaWiki:Gadget-" .. item) then
						is_gadget = true

						output:insert("<dd> ''This script is a part of the <code>")
						output:insert(gadget)
						output:insert("</code> gadget ([")
						output:insert(tostring(mw.uri.fullUrl('MediaWiki:Gadgets-definition', 'action=edit')))
						output:insert(" edit definitions])'' <dl>")
						
						output:insert("<dd> ''Description ([")
						output:insert(tostring(mw.uri.fullUrl('MediaWiki:Gadget-' .. gadget, 'action=edit')))
						output:insert(" edit])'': ")
						
						local gadget_description = mw.message.new('Gadget-' .. gadget):plain()
						gadget_description = frame:preprocess(gadget_description)
						output:insert(gadget_description)
						output:insert(" </dd>")

						items:remove(i)
						if #items > 0 then
							for j, item in ipairs(items) do
								items[j] = '[[MediaWiki:Gadget-' .. item .. '|' .. item .. ']]'
							end
							output:insert("<dd> ''Other parts'': ")
							output:insert(mw.text.listToText(items))
							output:insert("</dd>")
						end

						output:insert("</dl></dd>")

						break
					end
				end
			end
		end
		
		if not is_gadget then
			output:insert("<dd> ''This script is not a part of any [")
			output:insert(tostring(mw.uri.fullUrl('Special:Gadgets', 'uselang=en')))
			output:insert(' gadget] ([')
			output:insert(tostring(mw.uri.fullUrl('MediaWiki:Gadgets-definition', 'action=edit')))
			output:insert(' edit definitions]).</dd>')
		-- else
			-- cats:insert("Wiktionary gadgets")
		end
	end
	
	if old_doc_title then
		output:insert("<dd> ''Redirected from'' [")
		output:insert(old_doc_title:fullUrl { redirect = 'no' })
		output:insert(" ")
		output:insert(old_doc_title.fullText)
		output:insert("] ([")
		output:insert(old_doc_title:fullUrl { action = 'edit' })
		output:insert(" edit]).</dd>\n")
	end
	
	local links = Array()
	
	if title.isSubpage and not args.notsubpage then
		links:insert("[[:" .. title.nsText .. ":" .. title.rootText .. "|root page]]")
		links:insert("[[Special:PrefixIndex/" .. title.nsText .. ":" .. title.rootText .. "/|root page’s subpages]]")
	else
		links:insert("[[Special:PrefixIndex/" .. title.fullText .. "/|subpage list]]")
	end
	
	links:insert(
		'[' .. tostring(mw.uri.fullUrl('Special:WhatLinksHere/' .. title.fullText,
			'hidetrans=1&hideredirs=1')) .. ' links]')

	if contentModel ~= "Scribunto" then
		links:insert(
			'[' .. tostring(mw.uri.fullUrl('Special:WhatLinksHere/' .. title.fullText,
			'hidelinks=1&hidetrans=1')) .. ' redirects]')
	end

	if (contentModel == "javascript") or (contentModel == "css") then
		if user_name then
			links:insert("[[Special:MyPage" .. title.text:sub(#title.rootText + 1) .. "|your own]]")
		end
	else
		links:insert(
			'[' .. tostring(mw.uri.fullUrl('Special:WhatLinksHere/' .. title.fullText,
				'hidelinks=1&hideredirs=1')) .. ' transclusions]')
	end
	
	if contentModel == "Scribunto" then
		local is_testcases = title.isSubpage and title.subpageText == "testcases"
		local without_subpage = title.nsText .. ":" .. title.baseText
		if is_testcases then
			links:insert("[[:" .. without_subpage .. "|tested module]]")
		else
			links:insert("[[" .. title.fullText .. "/testcases|testcases]]")
		end
		
		if user_name then
			links:insert("[[User:" .. user_name .. "|user page]]")
			links:insert("[[User talk:" .. user_name .. "|user talk page]]")
			links:insert("[[Special:PrefixIndex/User:" .. user_name .. "/|userspace]]")
		else
			-- If sandbox module, add a link to the module that this is a sandbox of.
			-- Exclude user sandbox modules like [[User:Dine2016/sandbox]].
			if title.text:find("/sandbox%d*%f[/%z]") then
				cats:insert("Sandbox modules")
				
				-- Sandbox modules don’t really need documentation.
				needs_doc = false
				
				-- Will behave badly if “/sandbox” occurs twice in title!
				local sandbox_of = title.fullText:gsub("/sandbox%d*%f[/%z]", "")
				
				local diff
				if page_exists(sandbox_of) then
					diff = " (" .. compare_pages(title.fullText, sandbox_of, "diff") .. ")"
				else
					require("Module:debug").track("documentation/no sandbox of")
				end
				
				links:insert("[[:" .. sandbox_of .. "|sandbox of]]" .. (diff or ""))
			
			-- If not a sandbox module, add link to sandbox module.
			-- Sometimes there are multiple sandboxes for a single module:
			-- [[Module:sa-pronunc/sandbox]],  [[Module:sa-pronunc/sandbox2]].
			-- Occasionally sandbox modules have their own subpages that are also
			-- sandboxes: [[Module:grc-decl/sandbox/decl]].
			else
				local sandbox_title
				if title.fullText:find("^Module:grc%-decl/") then
					sandbox_title = title.fullText:gsub("^Module:grc%-decl/", "Module:grc-decl/sandbox/")
				elseif is_testcases then
					sandbox_title = title.fullText:gsub("/testcases", "/sandbox/testcases")
				else
					sandbox_title = title.fullText .. "/sandbox"
				end
				local sandbox_link = "[[:" .. sandbox_title .. "|sandbox]]"
				
				local diff
				if page_exists(sandbox_title) then
					diff = " (" .. compare_pages(title.fullText, sandbox_title, "diff") .. ")"
				end
				
				links:insert(sandbox_link .. (diff or ""))
			end
		end
	end
	
	if title.nsText == "Template" then
		-- Error search: all(any namespace), hastemplate (show pages using the template), insource (show source code), incategory (any/specific error) -- [[mw:Help:CirrusSearch]], [[w:Help:Searching/Regex]]
		-- apparently same with/without: &profile=advanced&fulltext=1
		local errorq = 'searchengineselect=mediawiki&search=all: hastemplate:\"'..title.rootText..'\" insource:\"'..title.rootText..'\" incategory:'
		local eincategory = "Pages_with_module_errors|ParserFunction_errors|DisplayTitle_errors|Pages_with_ISBN_errors|Pages_with_ISSN_errors|Pages_with_reference_errors|Pages_with_syntax_highlighting_errors|Pages_with_TemplateStyles_errors"
		
		links:insert(
			'[' .. tostring(mw.uri.fullUrl('Special:Search', errorq..eincategory )) .. ' errors]'
			.. ' (' ..
			'[' .. tostring(mw.uri.fullUrl('Special:Search', errorq..'ParserFunction_errors' )) .. ' parser]'
			.. '/' ..
			'[' .. tostring(mw.uri.fullUrl('Special:Search', errorq..'Pages_with_module_errors' )) .. ' module]'
			.. ')'
		)
		
		if title.isSubpage and title.text:find("/sandbox%d*%f[/%z]") then -- This is a sandbox template.
			-- At the moment there are no user sandbox templates with subpage
			-- “/sandbox”.
			cats:insert("Sandbox templates")
			
			-- Sandbox templates don’t really need documentation.
			needs_doc = false
			
			-- Will behave badly if “/sandbox” occurs twice in title!
			local sandbox_of = title.fullText:gsub("/sandbox%d*%f[/%z]", "")
			
			local diff
			if page_exists(sandbox_of) then
				diff = " (" .. compare_pages(title.fullText, sandbox_of, "diff") .. ")"
			else
				require("Module:debug").track("documentation/no sandbox of")
			end
			
			links:insert("[[:" .. sandbox_of .. "|sandbox of]]" .. (diff or ""))
		else -- This is a template that can have a sandbox.
			local sandbox_title = title.fullText .. "/sandbox"
			
			local diff
			if page_exists(sandbox_title) then
				diff = " (" .. compare_pages(title.fullText, sandbox_title, "diff") .. ")"
			end
			
			links:insert("[[:" .. sandbox_title .. "|sandbox]]" .. (diff or ""))
		end
	end
	
	if #links > 0 then
		output:insert("<dd> ''Useful links'': " .. links:concat(" • ") .. "</dd>")
	end
	
	output:insert("</dl>\n")
	
	-- Show error from [[Module:category tree/topic cat/data]] on its submodules'
	-- documentation to, for instance, warn about duplicate labels.
	if title.fullText:find("Module:category tree/topic cat/data", 1, true) == 1 then
		local ok, err = pcall(require, "Module:category tree/topic cat/data")
		if not ok then
			output:insert('<span class="error">' .. err .. '</span>\n\n')
		end
	end
	
	if doc_title.exists then
		-- Override automatic documentation, if present.
		doc_content = frame:expandTemplate { title = doc_title.fullText }
	elseif not doc_content and fallback_docs then
		doc_content = frame:expandTemplate {
			title = fallback_docs;
			args = {
				['user'] = user_name;
				['page'] = title.fullText;
				['skin name'] = skin_name;
			}
		}
	end

	if doc_content then
		output:insert(doc_content)
	end

	output:insert(('\n<%s style="clear: both;" />'):format(args.hr == "below" and "hr" or "br"))
	
	if not cats[1] and not doc_content then
		if contentModel == "Scribunto" then
			cats:insert("Uncategorized modules")
		-- elseif title.nsText == "Template" then
			-- cats:insert("Uncategorized templates")
		end
	end
	
	if needs_doc then
		cats:insert("Templates and modules needing documentation")
	end
	
	for _, cat in ipairs(cats) do
		output:insert("[[Category:" .. cat .. "]]")
	end
	
	output:insert("</div>\n")

	return output:concat()
end

-- Used by {{translit module documentation}}.
function export.translitModuleLangList(frame)
	local pagename, subpage
	
	if frame.args[1] then
		pagename = frame.args[1]
	else
		local title = mw.title.getCurrentTitle()
		subpage = title.subpageText
		pagename = title.text
		
		if subpage ~= pagename then
			pagename = title.rootText
		end
	end
	
	local translitModule = pagename
	
	local languageObjects = require("Module:languages/byTranslitModule")(translitModule)
	local codeInPagename = pagename:match("^([%l-]+)%-.*translit$")
	
	local categories = Array()
	local codeInPagenameInList = false
	if codeInPagename then
		if languageObjects[1] and subpage ~= "documentation" then
			local agreement = languageObjects[2] and "s" or ""
			categories:insert("[[Category:Transliteration modules used by " ..
				#languageObjects .. " language" .. agreement .. "]]")
		end
		
		languageObjects = Array(languageObjects)
			:filter(
				function (lang)
					local result = lang:getCode() ~= codeInPagename
					codeInPagenameInList = codeInPagenameInList or result
					return result
				end)
	end
	
	if subpage ~= "documentation" then
		for script_code in pagename:gmatch("%f[^-%z]%u%l%l%l%f[-]") do
			local script = require "Module:scripts".getByCode(script_code)
			if script then
				categories:insert("[[Category:" .. script:getCategoryName() .. "]]")
			end
		end
	end
	
	if subpage ~= "documentation" and not page_exists("Module:" .. pagename .. "/testcases") then
		categories:insert("[[Category:Transliteration modules without a testcases subpage]]")
	end
	
	if not languageObjects[1] then
		return categories:concat()
	end
	
	local langs = Array(languageObjects)
		:sort(
			function(lang1, lang2)
				return lang1:getCode() < lang2:getCode()
			end)
		-- This will not error because languageObjects is not empty.
		:map(languageObjects[1].makeCategoryLink)
		:serial_comma_join()
	
	return "It is " .. ( codeInPagenameInList and "also" or "" ) ..
		" used to transliterate " .. langs .. "." .. categories:concat()
end

-- Used by {{entry name module documentation}}.
function export.entryNameModuleLangList(frame)
	local pagename, subpage
	
	if frame.args[1] then
		pagename = frame.args[1]
	else
		local title = mw.title.getCurrentTitle()
		subpage = title.subpageText
		pagename = title.text
		
		if subpage ~= pagename then
			pagename = title.rootText
		end
	end
	
	local entryNameModule = pagename
	
	local languageObjects = require("Module:languages/byEntryNameModule")(entryNameModule)
	local codeInPagename = pagename:match("^([%l-]+)%-.*entryname$")
	
	local categories = Array()
	local codeInPagenameInList = false
	if codeInPagename then
		if languageObjects[1] and subpage ~= "documentation" then
			local agreement = languageObjects[2] and "s" or ""
			categories:insert("[[Category:Entry name-generating modules used by " ..
				#languageObjects .. " language" .. agreement .. "]]")
		end
		
		languageObjects = Array(languageObjects)
			:filter(
				function (lang)
					local result = lang:getCode() ~= codeInPagename
					codeInPagenameInList = codeInPagenameInList or result
					return result
				end)
	end
	
	if subpage ~= "documentation" then
		for script_code in pagename:gmatch("%f[^-%z]%u%l%l%l%f[-]") do
			local script = require "Module:scripts".getByCode(script_code)
			if script then
				categories:insert("[[Category:" .. script:getCategoryName() .. "]]")
			end
		end
	end
	
	if subpage ~= "documentation" and not page_exists("Module:" .. pagename .. "/testcases") then
		categories:insert("[[Category:Entry name-generating modules without a testcases subpage]]")
	end
	
	if not languageObjects[1] then
		return categories:concat()
	end
	
	local langs = Array(languageObjects)
		:sort(
			function(lang1, lang2)
				return lang1:getCode() < lang2:getCode()
			end)
		-- This will not error because languageObjects is not empty.
		:map(languageObjects[1].makeCategoryLink)
		:serial_comma_join()
	
	return "It is " .. ( codeInPagenameInList and "also" or "" ) ..
		" used to generate entry names for " .. langs .. "." .. categories:concat()
end

-- Used by {{sortkey module documentation}}.
function export.sortkeyModuleLangList(frame)
	local pagename, subpage
	
	if frame.args[1] then
		pagename = frame.args[1]
	else
		local title = mw.title.getCurrentTitle()
		subpage = title.subpageText
		pagename = title.text
		
		if subpage ~= pagename then
			pagename = title.rootText
		end
	end
	
	local sortkeyModule = pagename
	
	local languageObjects = require("Module:languages/bySortkeyModule")(sortkeyModule)
	local codeInPagename = pagename:match("^([%l-]+)%-.*sortkey$")
	
	local categories = Array()
	local codeInPagenameInList = false
	if codeInPagename then
		if languageObjects[1] and subpage ~= "documentation" then
			local agreement = languageObjects[2] and "s" or ""
			categories:insert("[[Category:Sortkey-generating modules used by " ..
				#languageObjects .. " language" .. agreement .. "]]")
		end
		
		languageObjects = Array(languageObjects)
			:filter(
				function (lang)
					local result = lang:getCode() ~= codeInPagename
					codeInPagenameInList = codeInPagenameInList or result
					return result
				end)
	end
	
	if subpage ~= "documentation" then
		for script_code in pagename:gmatch("%f[^-%z]%u%l%l%l%f[-]") do
			local script = require "Module:scripts".getByCode(script_code)
			if script then
				categories:insert("[[Category:" .. script:getCategoryName() .. "]]")
			end
		end
	end
	
	if subpage ~= "documentation" and not page_exists("Module:" .. pagename .. "/testcases") then
		categories:insert("[[Category:Sortkey-generating modules without a testcases subpage]]")
	end
	
	if not languageObjects[1] then
		return categories:concat()
	end
	
	local langs = Array(languageObjects)
		:sort(
			function(lang1, lang2)
				return lang1:getCode() < lang2:getCode()
			end)
		-- This will not error because languageObjects is not empty.
		:map(languageObjects[1].makeCategoryLink)
		:serial_comma_join()
	
	return "It is " .. ( codeInPagenameInList and "also" or "" ) ..
		" used to sort " .. langs .. "." .. categories:concat()
end

return export