Module:Age

-- Implement various "age of" and other date-related templates.

local mtext = { -- Message and other text that should be localized. ['mt-bad-param1'] =            'Invalid parameter $1', ['mt-bad-param2'] =            'Parameter $1=$2 is invalid', ['mt-bad-show'] =              'Parameter show=$1 is not supported here', ['mt-cannot-add'] =            'Cannot add "$1"', ['mt-conflicting-show'] =      'Parameter show=$1 conflicts with round=$2', ['mt-date-wrong-order'] =      'The second date must be later in time than the first date', ['mt-dd-future'] =             'Death date (first date) must not be in the future', ['mt-dd-wrong-order'] =        'Death date (first date) must be later in time than the birth date (second date)', ['mt-invalid-bd-age'] =        'Invalid birth date for calculating age', ['mt-invalid-dates-age'] =     'Invalid dates for calculating age', ['mt-invalid-end'] =           'Invalid end date in second parameter', ['mt-invalid-start'] =         'Invalid start date in first parameter', ['mt-need-jdn'] =              'Need valid Julian date number', ['mt-need-valid-bd'] =         'Need valid birth date: year, month, day', ['mt-need-valid-bd2'] =        'Need valid birth date (second date): year, month, day', ['mt-need-valid-date'] =       'Need valid date', ['mt-need-valid-dd'] =         'Need valid death date (first date): year, month, day', ['mt-need-valid-ymd'] =        'Need valid year, month, day', ['mt-need-valid-ymd-current'] = 'Need valid year|month|day or "currentdate"', ['mt-need-valid-ymd2'] =       'Second date should be year, month, day', ['mt-template-bad-name'] =     'The specified template name is not valid', ['mt-template-x'] =            'The template invoking this must have "|template=x" where x is the wanted operation', ['txt-age'] =                  '(age ',	['txt-aged'] =                  ' (aged ', ['txt-and'] =                  ' and ', ['txt-comma-and'] =            ', and ', ['txt-error'] =                'Error: ', ['txt-or'] =                   ' or ', }

local translate, from_en, to_en, isZero if translate then -- Functions to translate from en to local language and reverse go here. -- See example at bn:Module:বয়স. else from_en = function (text) return text end isZero = function (text) return tonumber(text) == 0 end end

local _Date, _currentDate local function getExports(frame) -- Return objects exported from the date module or its sandbox. if not _Date then local sandbox = frame:getTitle:find('sandbox', 1, true) and '/sandbox' or '' local datemod = require('Module:Date' .. sandbox) local realDate = datemod._Date _currentDate = datemod._current if to_en then _Date = function (...) local args = {} for i, v in ipairs({...}) do					args[i] = to_en(v) end return realDate(unpack(args)) end else _Date = realDate end end return _Date, _currentDate end

local Collection -- a table to hold items Collection = { add = function (self, item) if item ~= nil then self.n = self.n + 1 self[self.n] = item end end, join = function (self, sep) return table.concat(self, sep) end, remove = function (self, pos) if self.n > 0 and (pos == nil or (0 < pos and pos <= self.n)) then self.n = self.n - 1 return table.remove(self, pos) end end, sort = function (self, comp) table.sort(self, comp) end, new = function return setmetatable({n = 0}, Collection) end } Collection.__index = Collection

local function stripToNil(text) -- If text is a string, return its trimmed content, or nil if empty. -- Otherwise return text (which may, for example, be nil). if type(text) == 'string' then text = text:match('(%S.-)%s*$') end return text end

local function yes(parameter) -- Return true if parameter should be interpreted as "yes". -- Do not want to accept mixed upper/lowercase unless done by current templates. -- Need to accept "on" because "round=on" is wanted. return ({ y = true, yes = true, on = true })[parameter] end

local function message(msg, id) -- Return formatted message text for an error or warning. local function getText(msg) return mtext[msg] or error('Bug: message "' .. tostring(msg) .. '" not defined') end local text if type(msg) == 'table' then text = getText(msg[1]) local rep = {} for i, v in ipairs(msg) do			if i > 1 then rep['$' .. (i - 1)] = v			end end text = text:gsub('$%d+', rep) else text = getText(msg) end local categories = { error = '', warning = '', -- same as error until determine whether 'Age warning' would be worthwhile }	local a, b, category if id == 'warning' then a = ' [' b = '] ' else a = ' ' .. getText('txt-error') b = ' ' end if mw.title.getCurrentTitle:inNamespaces(0) then -- Category only in namespaces: 0=article. category = categories[id or 'error'] end return a .. mw.text.nowiki(text) .. b .. (category or '') end

local function formatNumber(number) -- Return the given number formatted with commas as group separators, -- given that the number is an integer. local numstr = tostring(number) local length = #numstr local places = Collection.new local pos = 0 repeat places:add(pos) pos = pos + 3 until pos >= length places:add(length) local groups = Collection.new for i = places.n, 2, -1 do		local p1 = length - places[i] + 1 local p2 = length - places[i - 1] groups:add(numstr:sub(p1, p2)) end return groups:join(',') end

local function spellNumber(number, options, i)	-- Return result of spelling number, or -- return number (as a string) if cannot spell it. -- i == 1 for the first number which can optionally start with an uppercase letter. number = tostring(number) return require('Module:ConvertNumeric').spell_number(		number,		nil,                      -- fraction numerator		nil,                       -- fraction denominator		i == 1 and options.upper,  -- true: 'One' instead of 'one'		not options.us,            -- true: use 'and' between tens/ones etc		options.adj,               -- true: hyphenated		options.ordinal            -- true: 'first' instead of 'one'	) or number end

local function makeExtra(args, flagCurrent) -- Return extra text that will be inserted before the visible result -- but after any sort key. local extra = args.prefix or '' if mw.ustring.len(extra) > 1 then -- Parameter "~" gives "~3" whereas "over" gives "over 3". if extra:sub(-6, -1) ~= ' ' then extra = extra .. ' '		end end if flagCurrent then extra = ' ' .. extra end return extra end

local function makeSort(value, sortable) -- Return a sort key if requested. -- Assume value is a valid number which has not overflowed. if sortable == 'sortable_table' or sortable == 'sortable_on' or sortable == 'sortable_debug' then local sortKey if value == 0 then sortKey = '5000000000000000000' else local mag = math.floor(math.log10(math.abs(value)) + 1e-14) if value > 0 then sortKey = 7000 + mag else sortKey = 2999 - mag value = value + 10^(mag+1) end sortKey = string.format('%d', sortKey) .. string.format('%015.0f', math.floor(value * 10^(14-mag))) end local result if sortable == 'sortable_table' then result = 'data-sort-value="_SORTKEY_"|' elseif sortable == 'sortable_debug' then result = ' _SORTKEY_♠ ' else result = ' ' end return result:gsub('_SORTKEY_', sortKey) end end

local translateParameters = { abbr = { off = 'abbr_off', on = 'abbr_on', },	disp = { age = 'disp_age', raw = 'disp_raw', },	format = { raw = 'format_raw', commas = 'format_commas', },	round = { on = 'on', yes = 'on', months = 'ym', weeks = 'ymw', days = 'ymd', hours = 'ymdh', },	sep = { comma = 'sep_comma', [','] = 'sep_comma', serialcomma = 'sep_serialcomma', space = 'sep_space', },	show = { hide = { id = 'hide' }, y = { 'y', id = 'y' }, ym = { 'y', 'm', id = 'ym' }, ymd = { 'y', 'm', 'd', id = 'ymd' }, ymw = { 'y', 'm', 'w', id = 'ymw' }, ymwd = { 'y', 'm', 'w', 'd', id = 'ymwd' }, yd = { 'y', 'd', id = 'yd', keepZero = true }, m = { 'm', id = 'm' }, md = { 'm', 'd', id = 'md' }, w = { 'w', id = 'w' }, wd = { 'w', 'd', id = 'wd' }, h = { 'H', id = 'h' }, hm = { 'H', 'M', id = 'hm' }, hms = { 'H', 'M', 'S', id = 'hms' }, d = { 'd', id = 'd' }, dh = { 'd', 'H', id = 'dh' }, dhm = { 'd', 'H', 'M', id = 'dhm' }, dhms = { 'd', 'H', 'M', 'S', id = 'dhms' }, ymdh = { 'y', 'm', 'd', 'H', id = 'ymdh' }, ymdhm = { 'y', 'm', 'd', 'H', 'M', id = 'ymdhm' }, ymwdh = { 'y', 'm', 'w', 'd', 'H', id = 'ymwdh' }, ymwdhm = { 'y', 'm', 'w', 'd', 'H', 'M', id = 'ymwdhm' }, },	sortable = { off = false, on = 'sortable_on', table = 'sortable_table', debug = 'sortable_debug', }, }

local spellOptions = { cardinal = {}, Cardinal = { upper = true }, cardinal_us = { us = true }, Cardinal_us = { us = true, upper = true }, ordinal = { ordinal = true }, Ordinal = { ordinal = true, upper = true }, ordinal_us = { ordinal = true, us = true }, Ordinal_us = { ordinal = true, us = true, upper = true }, }

local function dateExtract(frame) -- Return part of a date after performing an optional operation. local Date = getExports(frame) local args = frame:getParent.args local parms = {} for i, v in ipairs(args) do		parms[i] = v	end if yes(args.fix) then table.insert(parms, 'fix') end if yes(args.partial) then table.insert(parms, 'partial') end local show = stripToNil(args.show) or 'dmy' local date = Date(unpack(parms)) if not date then if show == 'format' then return 'error' end return message('mt-need-valid-date') end local add = stripToNil(args.add) if add then for item in add:gmatch('%S+') do			date = date + item if not date then return message({ 'mt-cannot-add', item }) end end end local sortKey, result local sortable = translateParameters.sortable[args.sortable] if sortable then local value = (date.partial and date.partial.first or date).jdz sortKey = makeSort(value, sortable) end if show ~= 'hide' then result = date[show] if result == nil then result = from_en(date:text(show)) elseif type(result) == 'boolean' then result = result and '1' or '0' else result = from_en(tostring(result)) end end return (sortKey or '') .. makeExtra(args) .. (result or '') end

local function rangeJoin(range) -- Return text to be used between a range of ages. return range == 'dash' and '–' or mtext['txt-or'] end

local function makeText(values, components, names, options, noUpper) -- Return wikitext representing an age or duration. local text = Collection.new local count = #values local sep = names.sep or '' for i, v in ipairs(values) do -- v is a number (say 4 for 4 years), or a table ({4,5} for 4 or 5 years). local islist = type(v) == 'table' if (islist or v > 0) or (text.n == 0 and i == count) or (text.n > 0 and components.keepZero) then local fmt, vstr if options.spell then fmt = function(number) return spellNumber(number, options.spell, noUpper or i)				end elseif i == 1 and options.format == 'format_commas' then -- Numbers after the first should be small and not need formatting. fmt = formatNumber else fmt = tostring end if islist then vstr = fmt(v[1]) .. rangeJoin(options.range) noUpper = true vstr = vstr .. fmt(v[2]) else vstr = fmt(v) end local name = names[components[i]] if name then local plural = names.plural if not plural or (islist and v[2] or v) == 1 then plural = '' end text:add(vstr .. sep .. name .. plural) else text:add(vstr) end end end local first, last if options.join == 'sep_space' then first = ' ' last = ' ' elseif options.join == 'sep_comma' then first = ', ' last = ', ' elseif options.join == 'sep_serialcomma' and text.n > 2 then first = ', ' last = mtext['txt-comma-and'] else first = ', ' last = mtext['txt-and'] end for i, v in ipairs(text) do		if i < text.n then text[i] = v .. (i + 1 < text.n and first or last) end end local sign = '' if options.isnegative then -- Do not display negative zero. if text.n > 1 or (text.n == 1 and text[1]:sub(1, 1) ~= '0' ) then if options.format == 'format_raw' then sign = '-' -- plain hyphen so result can be used in a calculation else sign = '−' -- Unicode U+2212 MINUS SIGN end end end return (options.sortKey or '') .. (options.extra or '') .. sign .. text:join .. (options.suffix or '') end

local function dateDifference(parms) -- Return a formatted date difference using the given parameters -- which have been validated. local names = { abbr_off = { plural = 's', sep = ' ', y = 'year', m = 'month', w = 'week', d = 'day', H = 'hour', M = 'minute', S = 'second', },		abbr_on = { y = 'y', m = 'm', w = 'w', d = 'd', H = 'h', M = 'm', S = 's', },		abbr_infant = {     -- for plural = 's', sep = ' ', y = 'yr', m = 'mo', w = 'wk', d = 'day', H = 'hr', M = 'min', S = 'sec', },		abbr_raw = {}, }	local diff = parms.diff -- must be a valid date difference local show = parms.show -- may be nil; default is set below local abbr = parms.abbr or 'abbr_off' local defaultJoin if abbr ~= 'abbr_off' then defaultJoin = 'sep_space' end if not show then show = 'ymd' if parms.disp == 'disp_age' then if diff.years < 3 then defaultJoin = 'sep_space' if diff.years >= 1 then show = 'ym' else show = 'md' end else show = 'y'			end end end if type(show) ~= 'table' then show = translateParameters.show[show] end if parms.disp == 'disp_raw' then defaultJoin = 'sep_space' abbr = 'abbr_raw' elseif parms.wantSc then defaultJoin = 'sep_serialcomma' end local diffOptions = { round = parms.round, duration = parms.wantDuration, range = parms.range and true or nil, }	local sortKey if parms.sortable then local value = diff.age_days + (parms.wantDuration and 1 or 0) -- days and fraction of a day if diff.isnegative then value = -value end sortKey = makeSort(value, parms.sortable) end local textOptions = { extra = parms.extra, format = parms.format, join = parms.sep or defaultJoin, isnegative = diff.isnegative, range = parms.range, sortKey = sortKey, spell = parms.spell, suffix = parms.suffix, -- not currently used }	if show.id == 'hide' then return sortKey or '' end local values = { diff:age(show.id, diffOptions) } if values[1] then return makeText(values, show, names[abbr], textOptions) end if diff.partial then -- Handle a more complex range such as		-- → 1 year, 12 days or 2 years, 11 days local opt = { format = textOptions.format, join = textOptions.join, isnegative = textOptions.isnegative, spell = textOptions.spell, }		return (textOptions.sortKey or '') .. makeText({ diff.partial.mindiff:age(show.id, diffOptions) }, show, names[abbr], opt) .. rangeJoin(textOptions.range) .. makeText({ diff.partial.maxdiff:age(show.id, diffOptions) }, show, names[abbr], opt, true) .. (textOptions.suffix or '') end return message({ 'mt-bad-show', show.id }) end

local function getDates(frame, getopt) -- Parse template parameters and return one of: -- * date        (a date table, if single) -- * date1, date2 (two date tables, if not single) -- * text        (a string error message) -- A missing date is optionally replaced with the current date. -- If wantMixture is true, a missing date component is replaced -- from the current date, so can get a bizarre mixture of -- specified/current y/m/d as has been done by some "age" templates. -- Some results may be placed in table getopt. local Date, currentDate = getExports(frame) getopt = getopt or {} local function flagCurrent(text) -- This allows the calling template to detect if the current date has been used, -- that is, whether both dates have been entered in a template expecting two. -- For example, an infobox may want the age when an event occurred, not the current age. -- Don't bother detecting if wantMixture is used because not needed and it is a poor option. if not text then if getopt.noMissing then return nil -- this gives a nil date which gives an error end text = 'currentdate' if getopt.flag == 'usesCurrent' then getopt.usesCurrent = true end end return text end local args = frame:getParent.args local fields = {} local isNamed = args.year or args.year1 or args.year2 or		args.month or args.month1 or args.month2 or		args.day or args.day1 or args.day2 if isNamed then fields[1] = args.year1 or args.year fields[2] = args.month1 or args.month fields[3] = args.day1 or args.day fields[4] = args.year2 fields[5] = args.month2 fields[6] = args.day2 else for i = 1, 6 do			fields[i] = args[i] end end local imax = 0 for i = 1, 6 do		fields[i] = stripToNil(fields[i]) if fields[i] then imax = i		end if getopt.omitZero and i % 3 ~= 1 then -- omit zero months and days as unknown values but keep year 0 which is 1 BCE if isZero(fields[i]) then fields[i] = nil getopt.partial = true end end end local fix = getopt.fix and 'fix' or '' local partialText = getopt.partial and 'partial' or '' local dates = {} if isNamed or imax >= 3 then local nrDates = getopt.single and 1 or 2 if getopt.wantMixture then -- Cannot be partial since empty fields are set from current. local components = { 'year', 'month', 'day' } for i = 1, nrDates * 3 do				fields[i] = fields[i] or currentDate[components[i > 3 and i - 3 or i]] end for i = 1, nrDates do				local index = i == 1 and 1 or 4 dates[i] = Date(fields[index], fields[index+1], fields[index+2]) end else -- If partial dates are allowed, accept --    year only, or			--     year and month only -- Do not accept year and day without a month because that makes no sense -- (and because, for example, Date('partial', 2001, nil, 12) sets day = nil, not 12). for i = 1, nrDates do				local index = i == 1 and 1 or 4 local y, m, d = fields[index], fields[index+1], fields[index+2] if (getopt.partial and y and (m or not d)) or (y and m and d) then dates[i] = Date(fix, partialText, y, m, d)				elseif not y and not m and not d then dates[i] = Date(flagCurrent) end end end else getopt.textdates = true -- have parsed each date from a single text field dates[1] = Date(fix, partialText, flagCurrent(fields[1])) if not getopt.single then dates[2] = Date(fix, partialText, flagCurrent(fields[2])) end end if not dates[1] then return message(getopt.missing1 or 'mt-need-valid-ymd') end if getopt.single then return dates[1] end if not dates[2] then return message(getopt.missing2 or 'mt-need-valid-ymd2') end return dates[1], dates[2] end

local function ageGeneric(frame) -- Return the result required by the specified template. -- Can use sortable=x where x = on/table/off/debug in any supported template. -- Some templates default to sortable=on but can be overridden. local name = frame.args.template if not name then return message('mt-template-x') end local args = frame:getParent.args local specs = { age_days = {               -- show = 'd', disp = 'disp_raw', },		age_full_years = {         -- 24 show = 'y', abbr = 'abbr_raw', flag = 'usesCurrent', omitZero = true, range = 'no', },		age_in_years = {           -- show = 'y', abbr = 'abbr_raw', negative = 'error', range = 'dash', },		age_infant = {             -- -- Do not set show because special processing is done later. abbr = yes(args.abbr) and 'abbr_infant' or 'abbr_off', disp = 'disp_age', sep = 'sep_space', sortable = 'on', },		age_m = {                  -- show = 'm', disp = 'disp_raw', },		age_w = {                  -- show = 'w', disp = 'disp_raw', },		age_wd = {                 -- show = 'wd', },		age_yd = {                 -- show = 'yd', format = 'format_commas', sep = args.sep ~= 'and' and 'sep_comma' or nil, },		age_ym = {                 -- show = 'ym', sep = 'sep_comma', },		age_ymd = {                -- show = 'ymd', range = true, },		age_ymwd = {               -- show = 'ymwd', wantMixture = true, },	}	local spec = specs[name] if not spec then return message('mt-template-bad-name') end if name == 'age_days' then local su = stripToNil(args['show unit']) if su then if su == 'abbr' or su == 'full' then spec.disp = nil spec.abbr = su == 'abbr' and 'abbr_on' or nil end end end local partial, autofill local range = stripToNil(args.range) or spec.range if range then -- Suppose partial dates are used and age could be 11 or 12 years. -- "|range=" (empty value) has no effect (spec is used). -- "|range=yes" or spec.range == true sets range = true (gives "11 or 12") -- "|range=dash" or spec.range == 'dash' sets range = 'dash' (gives "11–12"). -- "|range=no" or spec.range == 'no' sets range = nil and fills each date in the diff (gives "12"). --    ("on" is equivalent to "yes", and "off" is equivalent to "no"). -- "|range=OTHER" sets range = nil and rejects partial dates. range = ({ dash = 'dash', off = 'no', no = 'no', [true] = true })[range] or yes(range) if range then partial = true -- accept partial dates with a possible age range for the result if range == 'no' then autofill = true -- missing month/day in first or second date are filled from other date or 1 range = nil end end end local getopt = { fix = yes(args.fix), flag = stripToNil(args.flag) or spec.flag, omitZero = spec.omitZero, partial = partial, wantMixture = spec.wantMixture, }	local date1, date2 = getDates(frame, getopt) if type(date1) == 'string' then return date1 end local format = stripToNil(args.format) local spell = spellOptions[format] if format then format = 'format_' .. format elseif name == 'age_days' and getopt.textdates then format = 'format_commas' end local parms = { diff = date2:subtract(date1, { fill = autofill }), wantDuration = spec.duration or yes(args.duration), range = range, wantSc = yes(args.sc), show = args.show == 'hide' and 'hide' or spec.show, abbr = spec.abbr, disp = spec.disp, extra = makeExtra(args, getopt.usesCurrent and format ~= 'format_raw'), format = format or spec.format, round = yes(args.round), sep = spec.sep, sortable = translateParameters.sortable[args.sortable or spec.sortable], spell = spell, }	if (spec.negative or frame.args.negative) == 'error' and parms.diff.isnegative then return message('mt-date-wrong-order') end return from_en(dateDifference(parms)) end

local function bda(frame) -- Implement Template:Birth date and age. local args = frame:getParent.args local options = { missing1 = 'mt-need-valid-bd', noMissing = true, single = true, }	local date = getDates(frame, options) if type(date) == 'string' then return date -- error text end local Date = getExports(frame) local diff = Date('currentdate') - date if diff.isnegative or diff.years > 150 then return message('mt-invalid-bd-age') end local disp, show = 'disp_raw', 'y'	if diff.years < 2 then disp = 'disp_age' if diff.years == 0 and diff.months == 0 then show = 'd'		else show = 'm'		end end local df = stripToNil(args.df) -- day first (dmy); default is month first (mdy) local result = '( %-Y-%m-%d ) ' .. (df and '%-d %B %-Y' or '%B %-d, %-Y') result = from_en(' ' ..		date:text(result) ..		' ' ..		mtext['txt-age'] ..		dateDifference({ diff = diff, show = show, abbr = 'abbr_off', disp = disp, sep = 'sep_space', }) ..		') ')	local warnings = tonumber(frame.args.warnings)	if warnings and warnings > 0 then		local good = {			df = true,			mf = true,			day = true,			day1 = true,			month = true,			month1 = true,			year = true,			year1 = true,		}		local invalid		local imax = options.textdates and 1 or 3		for k, _ in pairs(args) do			if type(k) == 'number' then				if k > imax then					invalid = tostring(k)					break				end			else				if not good[k] then					invalid = k					break				end			end		end		if invalid then			result = result .. message({ 'mt-bad-param1', invalid }, 'warning')		end	end	return result end

local function dda(frame) -- Implement Template:Death date and age. local args = frame:getParent.args local options = { missing1 = 'mt-need-valid-dd', missing2 = 'mt-need-valid-bd2', noMissing = true, partial = true, }	local date1, date2 = getDates(frame, options) if type(date1) == 'string' then return date1 end local diff = date1 - date2 if diff.isnegative then return message('mt-dd-wrong-order') end local Date = getExports(frame) local today = Date('currentdate') + 1 -- one day in future allows for timezones if date1 > today then return message('mt-dd-future') end local years if diff.partial then years = diff.partial.years years = type(years) == 'table' and years[2] or years else years = diff.years end if years > 150 then return message('mt-invalid-dates-age') end local df = stripToNil(args.df) -- day first (dmy); default is month first (mdy) local result if date1.day then -- y, m, d known result = (df and			'%-d %B %-Y' or			'%B %-d, %-Y') .. ' (%-Y-%m-%d) ' elseif date1.month then -- y, m known; d unknown result = '%B %-Y' .. ' (%-Y-%m-00) ' else -- y known; m, d unknown result = '%-Y' .. ' (%-Y-00-00) ' end result = from_en(date1:text(result) ..		mtext['txt-aged'] ..		dateDifference({ diff = diff, show = 'y', abbr = 'abbr_off', disp = 'disp_raw', range = 'dash', sep = 'sep_space', }) ..		')')	local warnings = tonumber(frame.args.warnings)	if warnings and warnings > 0 then		local good = {			df = true,			mf = true,		}		local invalid		local imax = options.textdates and 2 or 6		for k, _ in pairs(args) do			if type(k) == 'number' then				if k > imax then					invalid = tostring(k)					break				end			else				if not good[k] then					invalid = k					break				end			end		end		if invalid then			result = result .. message({ 'mt-bad-param1', invalid }, 'warning')		end	end	return result end

local function dateToGsd(frame) -- Implement Template:Gregorian serial date. -- Return Gregorian serial date of the given date, or the current date. -- The returned value is negative for dates before 1 January 1 AD -- despite the fact that GSD is not defined for such dates. local date = getDates(frame, { wantMixture=true, single=true }) if type(date) == 'string' then return date end return tostring(date.gsd) end

local function jdToDate(frame) -- Return formatted date from a Julian date. -- The result includes a time if the input includes a fraction. -- The word 'Julian' is accepted for the Julian calendar. local Date = getExports(frame) local args = frame:getParent.args local date = Date('juliandate', args[1], args[2]) if date then return from_en(date:text) end return message('mt-need-jdn') end

local function dateToJd(frame) -- Return Julian date (a number) from a date which may include a time, -- or the current date ('currentdate') or current date and time ('currentdatetime'). -- The word 'Julian' is accepted for the Julian calendar. local Date = getExports(frame) local args = frame:getParent.args local date = Date(args[1], args[2], args[3], args[4], args[5], args[6], args[7]) if date then return tostring(date.jd) end return message('mt-need-valid-ymd-current') end

local function timeInterval(frame) -- Implement Template:Time interval. -- There are two positional arguments: date1, date2. -- The default for each is the current date and time. -- Result is date2 - date1 formatted. local Date = getExports(frame) local args = frame:getParent.args local parms = { extra = makeExtra(args), wantDuration = yes(args.duration), range = yes(args.range) or (args.range == 'dash' and 'dash' or nil), wantSc = yes(args.sc), }	local fix = yes(args.fix) and 'fix' or '' local date1 = Date(fix, 'partial', stripToNil(args[1]) or 'currentdatetime') if not date1 then return message('mt-invalid-start') end local date2 = Date(fix, 'partial', stripToNil(args[2]) or 'currentdatetime') if not date2 then return message('mt-invalid-end') end parms.diff = date2 - date1 for argname, translate in pairs(translateParameters) do		local parm = stripToNil(args[argname]) if parm then parm = translate[parm] if parm == nil then -- test for nil because false is a valid setting return message({ 'mt-bad-param2', argname, args[argname] }) end parms[argname] = parm end end if parms.round then local round = parms.round local show = parms.show if round ~= 'on' then if show then if show.id ~= round then return message({ 'mt-conflicting-show', args.show, args.round }) end else parms.show = translateParameters.show[round] end end parms.round = true end return from_en(dateDifference(parms)) end

return { age_generic = ageGeneric,          -- can emulate several age templates birth_date_and_age = bda,          -- Template:Birth_date_and_age death_date_and_age = dda,          -- Template:Death_date_and_age gsd = dateToGsd,                   -- Template:Gregorian_serial_date extract = dateExtract,             -- Template:Extract jd_to_date = jdToDate,             -- Template:? JULIANDAY = dateToJd,              -- Template:JULIANDAY time_interval = timeInterval,      -- Template:Time_interval }