Module:Labelled list hatnote

Module documentation This module is copied from the English Wikipedia page en:Module:Labelled list hatnote. It has no documentation, and relevant information may be found at the corresponding English Wikipedia documentation page. For more details see the editing history of the module. The above documentation is transcluded from Module:Labelled list hatnote/doc.

---

--------------------------------------------------------------------------------
--                               Labelled list                                --
--                                                                            --
-- This module does the core work of creating a hatnote composed of a list    --
-- prefixed by a colon-terminated label, i.e. "LABEL: [andList of pages]",    --
-- for {{see also}} and similar templates.                                    --
--------------------------------------------------------------------------------

local mHatnote = require('Module:Hatnote')
local mHatlist = require('Module:Hatnote list')
local mArguments --initialize lazily
local p = {}

-- Defaults global to this module
local defaults = {
	label = 'See also', --Final fallback for label argument
	labelForm = '%s: %s',
	prefixes = {'label', 'label ', 'l'},
	template = 'Module:Labelled list hatnote'
}

-- Helper function that pre-combines display parameters into page arguments.
-- Also compresses sparse arrays, as a desirable side-effect.
function p.preprocessDisplays (args, prefixes)
	-- Prefixes specify which parameters, in order, to check for display options
	-- They each have numbers auto-appended, e.g. 'label1', 'label 1', & 'l1'
	prefixes = prefixes or defaults.prefixes
	local pages = {}
	for k, v in pairs(args) do
		if type(k) == 'number' then
			local display
			for i = 1, #prefixes do
				display = args[prefixes[i] .. k]
				if display then break end
			end
			local page = display and
				string.format('%s|%s', string.gsub(v, '|.*$', ''), display) or v
			pages[#pages + 1] = page
		end
	end
	return pages
end

-- Produces a labelled pages-list hatnote.
-- The main frame (template definition) takes 1 or 2 arguments, for a singular
-- and (optionally) plural label respectively:
-- * {{#invoke:Labelled list hatnote|labelledList|Singular label|Plural label}}
-- The resulting template takes pagename & label parameters normally.
function p.labelledList (frame)
	mArguments = require('Module:Arguments')
	local labels = {frame.args[1] or defaults.label}
	labels[2] = frame.args[2] or labels[1]
	labels[3] = frame.args[3] --no defaulting
	labels[4] = frame.args[4] --no defaulting
	local template = frame:getParent():getTitle()
	local args = mArguments.getArgs(frame, {parentOnly = true})
	local pages = p.preprocessDisplays(args)
	local options = {
		extraclasses = frame.args.extraclasses,
		category = args.category,
		selfref = frame.args.selfref or args.selfref,
		template = template
	}
	return p._labelledList(pages, labels, options)
end

function p._labelledList (pages, labels, options)
	labels = labels or {}
	if #pages == 0 then
		return mHatnote.makeWikitextError(
			'no page names specified',
			(options.template or defaults.template) .. '#Errors',
			options.category
		)
	end
	label = (#pages == 1 and labels[1] or labels[2]) or defaults.label
	for k, v in pairs(pages) do 
		if mHatnote.findNamespaceId(v) ~= 0 then
			label =
				(
					#pages == 1 and
					(labels[3] or labels[1] or defaults.label) or
					(labels[4] or labels[2] or defaults.label)
				) or defaults.label
		end
	end
	local text = string.format(
		options.labelForm or defaults.labelForm,
		label,
		mHatlist.andList(pages, true)
	)
	local hnOptions = {
		extraclasses = options.extraclasses,
		selfref = options.selfref
	}
	return mHatnote._hatnote(text, hnOptions)
end

return p