모듈:Wikidata

-- vim: set noexpandtab ft=lua ts=4 sw=4:
require('strict')
local p = {}
local debug = false
------------------------------------------------------------------------------
-- module local variables and functions
local wiki = 
{
	langcode = mw.language.getContentLanguage().code
}
-- internationalisation
local i18n =
{
"errors" =
{
"property-not-found" = "Property not found.",
"entity-not-found" = "Wikidata entity not found.",
"unknown-claim-type" = "Unknown claim type.",
"unknown-entity-type" = "Unknown entity type.",
"qualifier-not-found" = "Qualifier not found.",
"site-not-found" = "Wikimedia project not found.",
		"unknown-datetime-format" = "Unknown datetime format.",
		"local-article-not-found" = "Article is not yet available in this wiki"
},
"datetime" =
	{
		-- $1 is a placeholder for the actual number
		0 = "$10억년",	-- precision: billion years
		1 = "$1억년",	-- precision: hundred million years
		2 = "$1천만년",	-- precision: ten million years
		3 = "$1백만년",	-- precision: million years
		4 = "$100,000년",		-- precision: hundred thousand years
		5 = "$10,000년",		-- precision: ten thousand years
		6 = "$1천년",	 	-- precision: millennium
		7 = "$1세기",			-- precision: century
		8 = "$1년대",				-- precision: decade
		-- the following use the format of #time parser function
		9  = "Y년",					-- precision: year, 
		10 = "Y년 n월",				-- precision: month
		11 = "Y년 n월 j일",			-- precision: day
		12 = "Y년 n월 j일 G시",			-- precision: hour
		13 = "Y년 n월 j일 H:i",		-- precision: minute
		14 = "Y년 n월 j일 H:i:s",		-- precision: second
		"beforenow" = "$1 BCE",	-- how to format negative numbers for precisions 0 to 5
		"afternow" = "$1 CE",		-- how to format positive numbers for precisions 0 to 5
		"bc" = '$1 "BCE"',		-- how print negative years
		"ad" = "$1",				-- how print positive years
		-- the following are for function getDateValue() and getQualifierDateValue()
		"default-format" = "ymd", -- default value of the #3 (getDateValue) or
								    -- #4 (getQualifierDateValue) argument
		"default-addon" = "BC",   -- default value of the #4 (getDateValue) or
									-- #5 (getQualifierDateValue) argument
		"prefix-addon" = false,   -- set to true for languages put "BC" in front of the
									-- datetime string; or the addon will be suffixed
		"addon-sep" = " ",		-- separator between datetime string and addon (or inverse)
		"format" =				-- options of the 3rd argument
		{
			"mdy" = "F j, Y",
			"my" = "F Y",
			"y" = "Y년",
			"dmy" = "j F Y",
			"ymd" = "Y년 n월 j일",
			"ym" = "Y년 n월"
		}
	},
	"monolingualtext" = '%text',
	"warnDump" = "",
	"ordinal" = 
	{
		1 = "st",
		2 = "nd",
		3 = "rd",
		"default" = "th"
	}
}
-- Credit to http://stackoverflow.com/a/1283608/2644759
-- cc-by-sa 3.0
local function tableMerge(t1, t2)
	for k,v in pairs(t2) do
		if type(v) == "table" then
			if type(t1k or false) == "table" then
				tableMerge(t1k or {}, t2k or {})
			else
				t1k = v
			end
		else
			t1k = v
	end
	end
	return t1
end
--local function loadI18n()
--	local exist, res = pcall(require, "Module:Wikidata/i18n")
--	if exist and next(res) ~= nil then
--		tableMerge(i18n, res.i18n)
--	end
--end
--loadI18n()
-- this function needs to be internationalised along with the above:
-- we need three exceptions in English for 1st, 2nd, 3rd
-- takes cardinal numer as a numeric and returns the ordinal as a string
local function makeOrdinal(cardinal)
	local ordsuffix = i18n.ordinal.default
	if cardinal % 10 == 1 then
		ordsuffix = i18n.ordinal1
	elseif cardinal % 10 == 2 then
		ordsuffix = i18n.ordinal2
	elseif cardinal % 10 == 3 then
		ordsuffix = i18n.ordinal3
	end
	return tostring(cardinal) .. ordsuffix
end
local function printError(code)
	return  .. (i18n.errorscode or code) .. 
end
local function parseDateValue(timestamp, date_format, date_addon)
	local prefix_addon = i18n"datetime""prefix-addon"
	local addon_sep = i18n"datetime""addon-sep"
	local addon = ""
	-- check for negative date
	if string.sub(timestamp, 1, 1) == '-' then
		timestamp = '+' .. string.sub(timestamp, 2)
		addon = date_addon
	end
	local function d(f)
		local year_suffix
		local tstr = ""
		local lang_obj = mw.language.new(wiki.langcode)
		local f_parts = mw.text.split(f, 'Y', true)
		for idx, f_part in pairs(f_parts) do
			year_suffix = 
			if string.match(f_part, "xmijkot$") then
				-- for non-Gregorian year
				f_part = f_part .. 'Y'
			elseif idx  0 then era = mw.ustring.gsub(mw.ustring.gsub(i18n.datetime.ad, '"', ""), "$1", era) end
		return era
	end

	-- precision is year
	if precision == 9 then
		return year
	end

	-- precision is less than years
	if precision > 9 then
		-- the following code replaces the UTC suffix with the given negated timezone to convert the global time to the given local time
		timezone = tonumber(timezone)
		if timezone and timezone ~= 0 then
			timezone = -timezone
			timezone = string.format("%.2d%.2d", timezone / 60, timezone % 60)
			if timezone1 ~= '-' then timezone = "+" .. timezone end
			date = mw.text.trim(date, "Z") .. " " .. timezone
		end
		--

		local formatstr = i18n.datetimeprecision
		if year == 0 then formatstr = mw.ustring.gsub(formatstr, i18n.datetime9, "")
		elseif year  0 and i18n.datetime.ad ~= "$1" then
			formatstr = mw.ustring.gsub(formatstr, i18n.datetime9, mw.ustring.gsub(i18n.datetime.ad, "$1", i18n.datetime9))
		end
		return mw.language.new(wiki.langcode):formatDate(formatstr, date)
	end
end
local function printDatavalueEntity(data, parameter)
	-- data fields: entity-type string, numeric-id int, Wikidata id
	local id
	
	if data"entity-type" == "item" then id = "Q" .. data"numeric-id"
	elseif data"entity-type" == "property" then id = "P" .. data"numeric-id"
	else return printError("unknown-entity-type")
	end
	
	if parameter then
		if parameter == "link" then
			local linkTarget = mw.wikibase.sitelink(id)
			local linkName = mw.wikibase.label(id)
			if linkTarget then
				-- if there is a local Wikipedia article link to it using the label or the article title
				return "" .. (linkName or linkTarget) .. ""
			else
				-- if there is no local Wikipedia article output the label or link to the Wikidata object to let the user input a proper label
				if linkName then return linkName else return "" .. id .. "" end
			end
		else
			return dataparameter
		end
	else
		return mw.wikibase.label(id) or id
	end
end
local function printDatavalueTime(data, parameter)
	-- data fields: time ISO 8601 time, timezone int in minutes, before int, after int, precision int, calendarmodel wikidata URI
	--   precision: 0 - billion years, 1 - hundred million years, ..., 6 - millennia, 7 - century, 8 - decade, 9 - year, 10 - month, 11 - day, 12 - hour, 13 - minute, 14 - second
	--   calendarmodel: e.g. http://www.wikidata.org/entity/Q1985727 for the proleptic Gregorian calendar or http://www.wikidata.org/wiki/Q11184 for the Julian calendar
	if parameter then
		if parameter == "calendarmodel" then data.calendarmodel = mw.ustring.match(data.calendarmodel, "Q%d+") -- extract entity id from the calendar model URI
		elseif parameter == "time" then data.time = normalizeDate(data.time) end
		return dataparameter
	else
		return formatDate(data.time, data.precision, data.timezone)
	end
end
local function printDatavalueMonolingualText(data, parameter)
	-- data fields: language string, text string
	if parameter then
		return dataparameter
	else
		local result = mw.ustring.gsub(mw.ustring.gsub(i18n.monolingualtext, "%%language", data"language"), "%%text", data"text")
		return result
	end
end
local function findClaims(entity, property)
	if not property or not entity or not entity.claims then return end

	if mw.ustring.match(property, "^P%d+$") then
		-- if the property is given by an id (P..) access the claim list by this id
		return entity.claimsproperty
	else
		property = mw.wikibase.resolvePropertyId(property)
		if not property then return end
		return entity.claimsproperty
	end
end
local function getSnakValue(snak, parameter)
	if snak.snaktype == "value" then
		-- call the respective snak parser
		if snak.datavalue.type == "string" then return snak.datavalue.value
		elseif snak.datavalue.type == "globecoordinate" then return printDatavalueCoordinate(snak.datavalue.value, parameter)
		elseif snak.datavalue.type == "quantity" then return printDatavalueQuantity(snak.datavalue.value, parameter)
		elseif snak.datavalue.type == "time" then return printDatavalueTime(snak.datavalue.value, parameter)
		elseif snak.datavalue.type == "wikibase-entityid" then return printDatavalueEntity(snak.datavalue.value, parameter)
		elseif snak.datavalue.type == "monolingualtext" then return printDatavalueMonolingualText(snak.datavalue.value, parameter)
		end
	end
	return mw.wikibase.renderSnak(snak)
end

local function getQualifierSnak(claim, qualifierId)
	-- a "snak" is Wikidata terminology for a typed key/value pair
	-- a claim consists of a main snak holding the main information of this claim,
	-- as well as a list of attribute snaks and a list of references snaks
	if qualifierId then
		-- search the attribute snak with the given qualifier as key
		if claim.qualifiers then
			local qualifier = claim.qualifiersqualifierId
			if qualifier then return qualifier1 end
		end
		return nil, printError("qualifier-not-found")
	else
		-- otherwise return the main snak
		return claim.mainsnak
	end
end

local function getValueOfClaim(claim, qualifierId, parameter)
	local error
	local snak
	snak, error = getQualifierSnak(claim, qualifierId)
	if snak then
		return getSnakValue(snak, parameter)
	else
		return nil, error
	end
end
local function getReferences(frame, claim)
	local result = ""
	-- traverse through all references
	for ref in pairs(claim.references or {}) do
		local refparts
		-- traverse through all parts of the current reference
		for snakkey, snakval in orderedpairs(claim.referencesref.snaks or {}, claim.referencesref"snaks-order") do
			if refparts then refparts = refparts .. ", " else refparts = "" end
			-- output the label of the property of the reference part, e.g. "imported from" for P143
			refparts = refparts .. tostring(mw.wikibase.label(snakkey)) .. ": " 
			-- output all values of this reference part, e.g. "German Wikipedia" and "English Wikipedia" if the referenced claim was imported from both sites
			for snakidx = 1, #snakval do
				if snakidx > 1 then refparts = refparts .. ", " end
				refparts = refparts .. getSnakValue(snakvalsnakidx)
			end
		end
		if refparts then result = result .. frame:extensionTag("ref", refparts) end
	end
	return result
end
------------------------------------------------------------------------------
-- module global functions
if debug then
	function p.inspectI18n(frame)
		local val = i18n
		for _, key in pairs(frame.args) do
			key = mw.text.trim(key)
			val = valkey
		end
		return val
	end
end
function p.descriptionIn(frame)
	local langcode = frame.args1
	local id = frame.args2	-- "id" must be nil, as access to other Wikidata objects is disabled in Mediawiki configuration
	-- return description of a Wikidata entity in the given language or the default language of this Wikipedia site
	return mw.wikibase.getEntityObject(id).descriptionslangcode or wiki.langcode.value
end
function p.labelIn(frame)
	local langcode = frame.args1
	local id = frame.args2	-- "id" must be nil, as access to other Wikidata objects is disabled in Mediawiki configuration
	-- return label of a Wikidata entity in the given language or the default language of this Wikipedia site
	return mw.wikibase.getEntityObject(id).labelslangcode or wiki.langcode.value
end
-- This is used to get a value, or a comma separated list of them if multiple values exist
p.getValue = function(frame)
	local propertyID = mw.text.trim(frame.args1 or "")
	local input_parm = mw.text.trim(frame.args2 or "")
	if input_parm == "값찾기" then
		local entity = mw.wikibase.getEntityObject()
		local claims
		if entity and entity.claims then
			claims = entity.claimspropertyID
		end
		if claims then
			-- if wiki-linked value output as link if possible
			if (claims1 and claims1.mainsnak.snaktype == "value" and claims1.mainsnak.datavalue.type == "wikibase-entityid") then
				local out = {}
				local continue = false;
				for k, v in pairs(claims) do
					continue = false
					if v.mainsnak.datavalue == nil then
						continue = true
					end
					if not continue then
						local sitelink = mw.wikibase.sitelink("Q" .. v.mainsnak.datavalue.value"numeric-id")
						local label = mw.wikibase.label("Q" .. v.mainsnak.datavalue.value"numeric-id")
						if label == nil then label = "Q" .. v.mainsnak.datavalue.value"numeric-id" end
							
						if sitelink then
							out#out + 1 = "" .. label .. ""
						else
							out#out + 1 = ":d:Q" .. v.mainsnak.datavalue.value"numeric-id" .. "|" .. label .. "*"
						end
					end
				end
				return table.concat(out, ", ")
			else
				-- just return best vakues
				return entity:formatPropertyValues(propertyID).value
			end
		else
			return ""
		end
	else
		return input_parm
	end
end
-- This is used to get a value, or a comma separated list of them if multiple values exist
-- from an arbitrary entry by using its QID.
-- Use : 값찾기
-- E.g.: 값찾기 - to fetch value of 'spouse' (P26) from 'Richard Burton' (Q151973)
-- Please use sparingly - this is an *expensive call*.
p.getValueFromID = function(frame)
	local itemID = mw.text.trim(frame.args1 or "")
	local propertyID = mw.text.trim(frame.args2 or "")
	local input_parm = mw.text.trim(frame.args3 or "")
	if input_parm == "값찾기" then
		local entity = mw.wikibase.getEntity(itemID)
		local claims = entity.claimspropertyID
		if claims then
			-- if wiki-linked value output as link if possible
			if (claims1 and claims1.mainsnak.snaktype == "value" and claims1.mainsnak.datavalue.type == "wikibase-entityid") then
				local out = {}
				for k, v in pairs(claims) do
					local sitelink = mw.wikibase.sitelink("Q" .. v.mainsnak.datavalue.value"numeric-id")
					local label = mw.wikibase.label("Q" .. v.mainsnak.datavalue.value"numeric-id")
					if label == nil then label = "Q" .. v.mainsnak.datavalue.value"numeric-id" end
							
					if sitelink then
						out#out + 1 = "" .. label .. ""
					else
						out#out + 1 = ":d:Q" .. v.mainsnak.datavalue.value"numeric-id" .. "|" .. label .. "*"
					end
				end
				return table.concat(out, ", ")
			else
				return entity:formatPropertyValues(propertyID).value
			end
		else
			return ""
		end
	else
		return input_parm
	end
end
p.getQualifierValue = function(frame)
	local propertyID = mw.text.trim(frame.args1 or "")
	local qualifierID = mw.text.trim(frame.args2 or "")
	local input_parm = mw.text.trim(frame.args3 or "")
	if input_parm == "값찾기" then
		local entity = mw.wikibase.getEntityObject()
		if entity.claimspropertyID ~= nil then
			local out = {}
			for k, v in pairs(entity.claimspropertyID) do
				for k2, v2 in pairs(v.qualifiersqualifierID) do
					if v2.snaktype == 'value' then
						if (mw.wikibase.sitelink("Q" .. v2.datavalue.value"numeric-id")) then
							out#out + 1 = "" .. mw.wikibase.sitelink("Q" .. v2.datavalue.value"numeric-id") .. ""
						else
							out#out + 1 = ":d:Q" .. v2.datavalue.value"numeric-id" .. "|" .. mw.wikibase.label("Q" .. v2.datavalue.value"numeric-id") .. "*"
						end
					end
				end
			end
			return table.concat(out, ", ")
		else
			return ""
		end
	else
		return input_parm
	end
end
-- This is used to get a value like 'male' (for property p21) which won't be linked and numbers without the thousand separators
p.getRawValue = function(frame)
	local propertyID = mw.text.trim(frame.args1 or "")
	local input_parm = mw.text.trim(frame.args2 or "")
	if input_parm == "값찾기" then
		local entity = mw.wikibase.getEntityObject()
		local claims
		if entity and entity.claims then claims = entity.claimspropertyID end
		if claims then
			local result = entity:formatPropertyValues(propertyID, mw.wikibase.entity.claimRanks).value
		
			-- if number type: remove thousand separators, bounds and units
			if (claims1 and claims1.mainsnak.snaktype == "value" and claims1.mainsnak.datavalue.type == "quantity") then
				result = mw.ustring.gsub(result, "(%d),(%d)", "%1%2")
				result = mw.ustring.gsub(result, "(%d)±.*", "%1")
			end
			return result
		else
			return ""
		end
	else
		return input_parm
	end
end
-- This is used to get the unit name for the numeric value returned by getRawValue
p.getUnits = function(frame)
	local propertyID = mw.text.trim(frame.args1 or "")
	local input_parm = mw.text.trim(frame.args2 or "")
	if input_parm == "값찾기" then
		local entity = mw.wikibase.getEntityObject()
		local claims
		if entity and entity.claims then claims = entity.claimspropertyID end
		if claims then
			local result = entity:formatPropertyValues(propertyID, mw.wikibase.entity.claimRanks).value
			if (claims1 and claims1.mainsnak.snaktype == "value" and claims1.mainsnak.datavalue.type == "quantity") then
				result = mw.ustring.sub(result, mw.ustring.find(result, " ")+1, -1)
			end
			return result
		else
			return ""
		end
	else
		return input_parm
	end
end
-- This is used to get the unit's QID to use with the numeric value returned by getRawValue
p.getUnitID = function(frame)
	local propertyID = mw.text.trim(frame.args1 or "")
	local input_parm = mw.text.trim(frame.args2 or "")
	if input_parm == "값찾기" then
		local entity = mw.wikibase.getEntityObject()
		local claims
		if entity and entity.claims then claims = entity.claimspropertyID end
		if claims then
			local result
			if (claims1 and claims1.mainsnak.snaktype == "value" and claims1.mainsnak.datavalue.type == "quantity") then
				-- get the url for the unit entry on Wikidata:
				result = claims1.mainsnak.datavalue.value.unit
				-- and just reurn the last bit from "Q" to the end (which is the QID):
				result = mw.ustring.sub(result, mw.ustring.find(result, "Q"), -1)
			end
			return result
		else
			return ""
		end
	else
		return input_parm
	end
end
p.getRawQualifierValue = function(frame)
	local propertyID = mw.text.trim(frame.args1 or "")
	local qualifierID = mw.text.trim(frame.args2 or "")
	local input_parm = mw.text.trim(frame.args3 or "")
	if input_parm == "값찾기" then
		local entity = mw.wikibase.getEntityObject()
		if entity.claimspropertyID ~= nil then
			local out = {}
			for k, v in pairs(entity.claimspropertyID) do
				for k2, v2 in pairs(v.qualifiersqualifierID) do
					if v2.snaktype == 'value' then
						if v2.datavalue.value"numeric-id" then
							out#out + 1 = mw.wikibase.label("Q" .. v2.datavalue.value"numeric-id")
						else
							out#out + 1 = v2.datavalue.value
						end
					end
				end
			end
			local ret = table.concat(out, ", ")
			return string.upper(string.sub(ret, 1, 1)) .. string.sub(ret, 2)
		else
			return ""
		end
	else
		return input_parm
	end
end
-- This is used to get a date value for date_of_birth (P569), etc. which won't be linked
-- Dates and times are stored in ISO 8601 format (sort of).
-- At present the local formatDate(date, precision, timezone) function doesn't handle timezone
-- So I'll just supply "Z" in the call to formatDate below:
p.getDateValue = function(frame)
	local propertyID = mw.text.trim(frame.args1 or "")
	local input_parm = mw.text.trim(frame.args2 or "")
	local date_format = mw.text.trim(frame.args3 or i18n"datetime""default-format")
	local date_addon = mw.text.trim(frame.args4 or i18n"datetime""default-addon")
	if input_parm == "값찾기" then
		local entity = mw.wikibase.getEntityObject()
		if entity.claimspropertyID ~= nil then
			local out = {}
			for k, v in pairs(entity.claimspropertyID) do
				if v.mainsnak.datavalue.type == 'time' then
					local timestamp = v.mainsnak.datavalue.value.time
					local dateprecision = v.mainsnak.datavalue.value.precision
					out#out + 1 = parseDateFull(timestamp, dateprecision, date_format, date_addon)
				end
			end
			return table.concat(out, ", ")
		else
			return ""
		end
	else
		return input_parm
	end
end
p.getQualifierDateValue = function(frame)
	local propertyID = mw.text.trim(frame.args1 or "")
	local qualifierID = mw.text.trim(frame.args2 or "")
	local input_parm = mw.text.trim(frame.args3 or "")
	local date_format = mw.text.trim(frame.args4 or i18n"datetime""default-format")
	local date_addon = mw.text.trim(frame.args5 or i18n"datetime""default-addon")
	if input_parm == "값찾기" then
		local entity = mw.wikibase.getEntityObject()
		if entity.claimspropertyID ~= nil then
			local out = {}
			for k, v in pairs(entity.claimspropertyID) do
				for k2, v2 in pairs(v.qualifiersqualifierID) do
					if v2.snaktype == 'value' then
						local timestamp = v2.datavalue.value.time
						out#out + 1 = parseDateValue(timestamp, date_format, date_addon)
					end
				end
			end
			return table.concat(out, ", ")
		else
			return ""
		end
	else
		return input_parm
	end
end
-- This is used to fetch all of the images with a particular property, e.g. image (P18), Gene Atlas Image (P692), etc.
-- Parameters are | propertyID | value / 값찾기 / nil | separator (default=space) | size (default=frameless)
-- It will return a standard wiki-markup  size for each image with a selectable size and separator (which may be html)
-- e.g. 값찾기
-- e.g. 250px
-- If a property is chosen that is not of type "commonsMedia", it will return empty text.
p.getImages = function(frame)
	local propertyID = mw.text.trim(frame.args1 or "")
	local input_parm = mw.text.trim(frame.args2 or "")
	local sep = mw.text.trim(frame.args3 or " ")
	local imgsize = mw.text.trim(frame.args4 or "frameless")
	if input_parm == "값찾기" then
		local entity = mw.wikibase.getEntityObject()
		local claims
		if entity and entity.claims then
			claims = entity.claimspropertyID
		end
		if claims then
			if (claims1 and claims1.mainsnak.datatype == "commonsMedia") then
				local out = {}
				for k, v in pairs(claims) do
					local filename = v.mainsnak.datavalue.value
					out#out + 1 = "" .. imgsize .. ""
				end
				return table.concat(out, sep)
			else
				return ""
			end
		else
			return ""
		end
	else
		return input_parm
	end
end
-- This is used to get the TA98 (Terminologia Anatomica first edition 1998) values like 'A01.1.00.005' (property P1323)
-- which are then linked to http://www.unifr.ch/ifaa/Public/EntryPage/TA98%20Tree/Entity%20TA98%20EN/01.1.00.005%20Entity%20TA98%20EN.htm
-- uses the newer mw.wikibase calls instead of directly using the snaks
-- formatPropertyValues returns a table with the P1323 values concatenated with ", " so we have to split them out into a table in order to construct the return string
p.getTAValue = function(frame)
	local ent = mw.wikibase.getEntityObject()
	local props = ent:formatPropertyValues('P1323')
	local out = {}
	local t = {}
	for k, v in pairs(props) do
		if k == 'value' then
			t = mw.text.split( v, ", ")
			for k2, v2 in pairs(t) do
				out#out + 1 = " .. string.sub(v2, 2) .. "%20Entity%20TA98%20EN.htm " .. v2 .. ""
			end
		end
	end
	local ret = table.concat(out, " ")
	if #ret == 0 then
		ret = "Invalid TA"
	end
	return ret
end
--
This is used to return an image legend from Wikidata
image is property P18
image legend is property P2096
Call as id=
Returns PARAMETER, unless it is equal to "값찾기", from Item QID (expensive call)
If QID is omitted or blank, the current article is used (not an expensive call)
If lang is omitted, it uses the local wiki language, otherwise it uses the provided ISO-639 language code
ISO-639: https://docs.oracle.com/cd/E13214_01/wli/docs92/xref/xqisocodes.html#wp1252447
Ranks are: 'preferred' > 'normal'
This returns the label from the first image with 'preferred' rank
Or the label from the first image with 'normal' rank if preferred returns nothing
Ranks: https://www.mediawiki.org/wiki/Extension:Wikibase_Client/Lua
p.getImageLegend = function(frame)
	-- look for named parameter id; if it's blank make it nil
	local id = frame.args.id
	if id and (#id == 0) then
		id = nil
	end
	
	-- look for named parameter lang
	-- it should contain a two-character ISO-639 language code
	-- if it's blank fetch the language of the local wiki
	local lang = frame.args.lang
	if (not lang) or (#lang "..mw.dumpObject(data).."".. i18n.warnDump
		end
		data = dataindex or datatonumber(index)
		if not data then
			return i18n.warnDump
		end
		i = i + 1
	end
end
return p