ਮੌਡਿਊਲ:Age

This module is subject to page protection. It is a highly visible module in use by a very large number of pages, or is substituted very frequently. Because vandalism or mistakes would affect many pages, and even trivial editing might cause substantial load on the servers, it is protected from editing.

This Lua module is used on many pages and changes may be widely noticed. Test changes in the module's /sandbox or /testcases subpages, or in your own module sandbox. Consider discussing changes on the talk page before implementing them.

Templates supported

Module:Age implements the following templates:

Template	Required wikitext
{{extract}}	`{{#invoke:age\|extract}}`
{{gregorian serial date}}	`{{#invoke:age\|gsd}}`
{{time interval}}	`{{#invoke:age\|time_interval}}`
{{age in days}}	`{{#invoke:age\|age_generic\|template=age_days}}`
{{age in days nts}}	`{{#invoke:age\|age_generic\|template=age_days_nts}}`
{{duration in days}}	`{{#invoke:age\|age_generic\|template=duration_days}}`
{{duration in days nts}}	`{{#invoke:age\|age_generic\|template=duration_days_nts}}`
{{age}}	`{{#invoke:age\|age_generic\|template=age_full_years}}`
{{age nts}}	`{{#invoke:age\|age_generic\|template=age_full_years_nts}}`
{{age in years}}	`{{#invoke:age\|age_generic\|template=age_in_years}}`
{{age in years nts}}	`{{#invoke:age\|age_generic\|template=age_in_years_nts}}`
{{age for infant}}	`{{#invoke:age\|age_generic\|template=age_infant}}`
{{age in months}}	`{{#invoke:age\|age_generic\|template=age_m}}`
{{age in weeks}}	`{{#invoke:age\|age_generic\|template=age_w}}`
{{age in weeks and days}}	`{{#invoke:age\|age_generic\|template=age_wd}}`
{{age in years and days}}	`{{#invoke:age\|age_generic\|template=age_yd}}`
{{age in years and days nts}}	`{{#invoke:age\|age_generic\|template=age_yd_nts}}`
{{age in years and months}}	`{{#invoke:age\|age_generic\|template=age_ym}}`
{{age in years, months and days}}	`{{#invoke:age\|age_generic\|template=age_ymd}}`
{{age in years, months, weeks and days}}	`{{#invoke:age\|age_generic\|template=age_ymwd}}`
{{birth date and age}}	`{{#invoke:age\|birth_date_and_age}}`
{{death date and age}}	`{{#invoke:age\|death_date_and_age}}`

Redirects

Template	Redirects to
{{ayd}}	{{age in years and days nts}}
{{hla}}	{{age in years, months and days}}
{{age in months, weeks and days}}	{{age in years, months, weeks and days}}
{{bda}}	{{birth date and age}}
{{dda}}	{{death date and age}}
{{gsd}}	{{gregorian serial date}}

The age templates expect the older date to be first. The implementations of age_in_years and age_in_years_nts display an error message if that is not the case. If similar checking is wanted for other templates, negative=error can be added to the invoke. For example, {{age}} might use:

{{#invoke:age|age_generic|template=age_full_years|negative=error}}

If negative=error does not apply, a negative difference is indicated with a minus sign (−).

Date formats

Dates can use numbered or named parameters to specify year/month/day. Alternatively, a full date can be entered in a variety of formats. For example:

{{age in years and months|year1=2001|month1=1|day1=10|year2=2012|month2=2|day2=20}} → 11 ਸਾਲ, 1 ਮਹੀਨਾ
{{age in years and months|year=2001|month=1|day=10|year2=2012|month2=2|day2=20}} → 11 ਸਾਲ, 1 ਮਹੀਨਾ
{{age in years and months|2001|1|10|2012|2|20}} → 11 ਸਾਲ, 1 ਮਹੀਨਾ
{{age in years and months|2001-1-10|2012-2-20}} → 11 ਸਾਲ, 1 ਮਹੀਨਾ
{{age in years and months|10 Jan 2001|20 Feb 2012}} → 11 ਸਾਲ, 1 ਮਹੀਨਾ
{{age in years and months|January 10, 2001|Feb 20, 2012}} → 11 ਸਾਲ, 1 ਮਹੀਨਾ

If the first or second date is omitted, the current date is used. For example:

{{age in years and months|year2=2012|month2=2|day2=20}} → −12 ਸਾਲ, 10 ਮਹੀਨੇ
{{age in years and months||||2012|2|20}} → −12 ਸਾਲ, 10 ਮਹੀਨੇ
{{age in years and months||2012-2-20}} → −12 ਸਾਲ, 10 ਮਹੀਨੇ
{{age in years and months||20 Feb 2012}} → −12 ਸਾਲ, 10 ਮਹੀਨੇ
{{age in years and months||Feb 20, 2012}} → −12 ਸਾਲ, 10 ਮਹੀਨੇ
{{age in years and months|year1=2001|month1=1|day1=10}} → 23 ਸਾਲ, 11 ਮਹੀਨੇ
{{age in years and months|year=2001|month=1|day=10}} → 23 ਸਾਲ, 11 ਮਹੀਨੇ
{{age in years and months|2001|1|10}} → 23 ਸਾਲ, 11 ਮਹੀਨੇ
{{age in years and months|2001-1-10}} → 23 ਸਾਲ, 11 ਮਹੀਨੇ
{{age in years and months|10 Jan 2001}} → 23 ਸਾਲ, 11 ਮਹੀਨੇ
{{age in years and months|January 10, 2001}} → 23 ਸਾਲ, 11 ਮਹੀਨੇ

Parameters

The following options are available:

Parameter	Description
`duration=on`	The finishing date is included in the result; that adds one day to the age.
`fix=on`	Adjust invalid time units. See Template:Extract#Fix.
`format=commas`	A value of 1,000 or more is displayed with commas.
`format=raw`	Numbers are displayed without commas and negative numbers are displayed with a hyphen for `{{#expr}}`. In addition, {{age}} outputs a plain number and will not include a span to indicate if the result relies on the current date.
`format=cardinal`	Display the resulting number using words such as "five" instead of 5. See below.
`format=ordinal`	Display the resulting number using words such as "fifth" instead of 5. See below.
`prefix=text`	Insert the given text before the result but after any sort key. For example, `{{age\|23 July 1910\|14 July 1976\|prefix=about\|sortable=on}}` outputs a hidden sort key followed by "about 65".
`range=dash`	Accept a year only, or a year and month only, and show a range of ages with an en dash (–).
`range=yes`	Accept a year or year/month, and show the range with "or".
`range=no`	Accept a year only, or year/month, but show only a single age as if full dates had been entered.
`round=on`	The age is rounded to the nearest least-significant time unit.
`sc=on`	A serial comma is used (only useful when three or more values are displayed).
`sc=yes`	Same as `sc=on`.
`show=hide`	The age is not displayed; may be useful with `sortable=on`.
`sortable=on`	Insert a hidden sort key before the result (for use in sortable tables).
`sortable=table`	Insert a sort key using table syntax `data-sort-value="value"\|`.
`sortable=debug`	Same as `sortable=on` but the sort key is displayed for testing.
`sortable=off`	No sort key (can override the default for a template like {{age nts}}).

Examples using the range parameter follow.

{{age in years and months|year=2001|month=1|year2=2012|month2=2|range=yes}} → 11 ਸਾਲ, 0 ਜਾਂ 1 ਮਹੀਨਾ
{{age in years and months|2001|1||2012|2|range=yes}} → 11 ਸਾਲ, 0 ਜਾਂ 1 ਮਹੀਨਾ
{{age in years and months|Jan 2001|Feb 2012|range=yes}} → 11 ਸਾਲ, 0 ਜਾਂ 1 ਮਹੀਨਾ
{{age in years and months|Jan 2001|Feb 2012|range=dash}} → 11 ਸਾਲ, 0–1 ਮਹੀਨਾ
{{age in years and months|Jan 2001|Feb 2012|range=no}} → 11 ਸਾਲ, 1 ਮਹੀਨਾ (assume 1 Jan 2001 to 1 Feb 2012)
{{age in years and months|12 Jan 2001|Feb 2012|range=no}} → 11 ਸਾਲ, 1 ਮਹੀਨਾ (assume 12 Jan 2001 to 12 Feb 2012)
{{age in years and months|2001|2012|range=no}} → 11 ਸਾਲ (assume 1 Jan 2001 to 1 Jan 2012)
{{age in years and months|2001|23 Feb 2012|range=no}} → 11 ਸਾਲ (assume 23 Feb 2001 to 23 Feb 2012)

The sort key is based on the age in days, and fractions of a day if a time is specified.

{{age in years and months|10 Jan 2001|20 Feb 2012|sortable=debug}} → 7003405800000000000♠11 ਸਾਲ, 1 ਮਹੀਨਾ
{{age in years and months|10 Jan 2001|6:00 am 20 Feb 2012|sortable=debug}} → 7003405825000000000♠11 ਸਾਲ, 1 ਮਹੀਨਾ
{{age in years and months|10 Jan 2001|6:00 am 20 Feb 2012|sortable=debug|show=hide}} → 7003405825000000000♠

An extra day is added for a duration.

{{age in years and months|20 Jan 2001|19 Feb 2012}} → 11 ਸਾਲ (one day short of 11 years, 1 month)
{{age in years and months|20 Jan 2001|19 Feb 2012|duration=on}} → 11 ਸਾਲ, 1 ਮਹੀਨਾ

The least-significant time unit can be rounded.

{{age in years and months|20 Jan 2001|10 Feb 2012}} → 11 ਸਾਲ
{{age in years and months|20 Jan 2001|10 Feb 2012|round=on}} → 11 ਸਾਲ, 1 ਮਹੀਨਾ (round to nearest month)

Large numbers can be formatted with commas.

{{age in years and months|120|2012|format=commas|range=yes}} → 1,891 ਜਾਂ 1,892 ਸਾਲ
{{age in years and months|120|2012|format=commas|range=dash}} → 1,891–1,892 ਸਾਲ

Spelling numbers

The templates that use age_generic can display numbers in words rather than using numerals. The result can be a cardinal number (such as "five") or an ordinal number (such as "fifth"). The first letter can be in uppercase, and US spelling of numbers can be used. Examples:

{{age|1898|01|01|2018|02|01|format=cardinal}} → ਇੱਕ ਸੌ and twenty
{{age|1898|01|01|2018|02|01|format=cardinal_us}} → ਇੱਕ ਸੌ twenty
{{age|1898|01|01|2018|02|01|format=Cardinal}} → ਇੱਕ ਸੌ and twenty
{{age|1898|01|01|2018|02|01|format=Cardinal_us}} → ਇੱਕ ਸੌ twenty
{{age|1898|01|01|2018|02|01|format=Ordinal}} → ਇੱਕ ਸੌ and twentieth
{{age|1898|01|01|2018|02|01|format=Ordinal_us}} → ਇੱਕ ਸੌ twentieth
{{age|1898|01|01|2018|02|01|format=ordinal}} → ਇੱਕ ਸੌ and twentieth
{{age|1898|01|01|2018|02|01|format=ordinal_us}} → ਇੱਕ ਸੌ twentieth
{{age|1980|1990|range=yes|format=Cardinal}} → ਨੌ ਜਾਂ ਦਸ
{{age in years, months and days|April 1980|1995|format=Cardinal|range=yes}} → ਚੌਦਾਂ ਜਾਂ ਪੰਦਰਾਂ ਸਾਲ

Tracking category

Category:Age error (23)

Localization

Inputs and outputs can be localized to suit the language used. Examples are at bnwiki and bswiki.

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

local mtext = {
	-- Message and other text that should be localized.
	-- Also need to localize text in table names in function dateDifference.
	['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-and'] =                   ' ਅਤੇ ',
	['txt-or'] =                    '&nbsp;ਜਾਂ ',
	['txt-category'] =              'Category:Age error',
	['txt-comma-and'] =             ', ਅਤੇ ',
	['txt-error'] =                 'Error: ',
	['txt-format-default'] =        'mf',  -- 'df' (day first = dmy) or 'mf' (month first = mdy)
	['txt-module-convertnumeric'] = 'Module:ConvertNumeric',
	['txt-module-date'] =           'Module:Date',
	['txt-sandbox'] =               'sandbox',
	['txt-bda'] = '<span style="display:none"> (<span class="bday">$1</span>) </span>$2<span class="noprint ForceAgeToShow"> (ਉਮਰ&nbsp;$3)</span>',
	['txt-dda'] = '$2<span style="display:none">($1)</span> (ਉਮਰ&nbsp;$3)',
	['txt-bda-disp'] = 'disp_raw',  -- disp_raw → age is a number only; disp_age → age is a number and unit (normally years but months or days if very young)
	['txt-dda-disp'] = 'disp_raw',
	['txt-dmy'] = '%-d %B %-Y',
	['txt-mdy'] = '%B %-d, %-Y',
}

local isWarning = {
	['mt-bad-param1'] = true,
}

local translate = {
	digits = {
		from_en = {
			['0'] = '0',
			['1'] = '1',
			['2'] = '2',
			['3'] = '3',
			['4'] = '4',
			['5'] = '5',
			['6'] = '6',
			['7'] = '7',
			['8'] = '8',
			['9'] = '9',
		},
		to_en = {
			['0'] = '0',
			['1'] = '1',
			['2'] = '2',
			['3'] = '3',
			['4'] = '4',
			['5'] = '5',
			['6'] = '6',
			['7'] = '7',
			['8'] = '8',
			['9'] = '9',
		},
	},
	words = {
		from_en = {
			January   = 'ਜਨਵਰੀ',
			February  = 'ਫਰਵਰੀ',
			March     = 'ਮਾਰਚ',
			April     = 'ਅਪ੍ਰੈਲ',
			May       = 'ਮਈ',
			June      = 'ਜੂਨ',
			July      = 'ਜੁਲਾਈ',
			August    = 'ਅਗਸਤ',
			September = 'ਸਤੰਬਰ',
			October   = 'ਅਕਤੂਬਰ',
			November  = 'ਨਵੰਬਰ',
			December  = 'ਦਸੰਬਰ',
			Jan = 'ਜਨ',
			Feb = 'ਫਰ',
			Sep = 'ਸਤੰ',
			Oct = 'ਅਕਤੂ',
			Nov = 'ਨਵੰ',
			Dec = 'ਦਸੰ',
		},
		to_en = {
			['ਜਨਵਰੀ'] = 'January',
			['ਫਰਵਰੀ'] = 'February',
			['ਮਾਰਚ'] = 'March',
			['ਅਪ੍ਰੈਲ'] = 'April',
			['ਮਈ'] = 'May',
			['ਜੂਨ'] = 'June',
			['ਜੁਲਾਈ'] = 'July',
			['ਅਗਸਤ'] = 'August',
			['ਸਤੰਬਰ'] = 'September',
			['ਅਕਤੂਬਰ'] = 'October',
			['ਨਵੰਬਰ'] = 'November',
			['ਦਸੰਬਰ'] = 'December',
			['ਜਨ'] = 'Jan',
			['ਫਰ'] = 'Feb',
			['ਸਤੰ'] = 'Sep',
			['ਅਕਤੂ'] = 'Oct',
			['ਨਵੰ'] = 'Nov',
			['ਦਸੰ'] = 'Dec',
		},
	},
}

local from_en, to_en, isZero
if translate then
	-- Functions to translate from en to local language and reverse go here.
	-- See example at [[:pa:Module:age]].
	from_en = function (text)
		-- Translate en output to local language.
		return (text
				:gsub('%d', translate.digits.from_en)
				:gsub('%a+', translate.words.from_en))
	end
	to_en = function (text)
		text = mw.ustring.gsub(text, '%d', translate.digits.to_en)
		-- Translate input in local language to en.
		-- Following trick works for languages where all letters are non-ASCII.
		-- It is needed because mw.ustring pattern '%a+' only finds parts of a word.
		return (string.gsub(text, '[\128-\255]+', translate.words.to_en))
	end
	isZero = function (text)
		return tonumber((mw.ustring.gsub(text or '', '%d', translate.digits.to_en))) == 0
	end
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(mtext['txt-sandbox'], 1, true) and ('/' .. mtext['txt-sandbox']) or ''
		local datemod = require(mtext['txt-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 dateFormat(args)
	-- Return string for wanted date format.
	local default = mtext['txt-format-default']
	local other = default == 'df' and 'mf' or 'df'
	local wanted = stripToNil(args[other]) and other or default
	return wanted == 'df' and mtext['txt-dmy'] or mtext['txt-mdy']
end

local function substituteParameters(text, ...)
	-- Return text after substituting any given parameters for $1, $2, etc.
	return mw.message.newRawMessage(text, ...):plain()
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, ...)
	-- 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 categories = {
		error = mtext['txt-category'],
		warning = mtext['txt-category'],
	}
	local a, b, k, category
	local text = substituteParameters(getText(msg), ...)
	if isWarning[msg] then
		a = '<sup>[<i>'
		b = '</i>]</sup>'
		k = 'warning'
	else
		a = '<strong class="error">' .. getText('txt-error')
		b = '</strong>'
		k = 'error'
	end
	if mw.title.getCurrentTitle():inNamespaces(0) then
		-- Category only in namespaces: 0=article.
		category = '[[' .. categories[k] .. ']]'
	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(mtext['txt-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) ~= '&nbsp;' then
			extra = extra .. ' '
		end
	end
	if flagCurrent then
		extra = '<span class="currentage"></span>' .. 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 = '<span data-sort-value="_SORTKEY_♠"><span style="border:1px solid">_SORTKEY_♠</span></span>'
		else
			result = '<span data-sort-value="_SORTKEY_♠"></span>'
		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' },
		M = { 'M', id = 'M' },
		s = { 'S', id = 's' },
		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
				if type(name) == 'table' then
					name = mw.getContentLanguage():plural(islist and v[2] or v, name)
				end
				text:add(vstr .. sep .. name)
			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 = {
		-- Each name is:
		-- * a string if no plural form of the name is used; or
		-- * a table of strings, one of which is selected using the rules at
		--   https://translatewiki.net/wiki/Plural/Mediawiki_plural_rules
		abbr_off = {
			sep = '&nbsp;',
			y = {'ਸਾਲ', 'ਸਾਲ'},
			m = {'ਮਹੀਨਾ', 'ਮਹੀਨੇ'},
			w = {'ਹਫਤਾ', 'ਹਫਤੇ'},
			d = {'ਦਿਨ', 'ਦਿਨ'},
			H = {'ਘੰਟਾ', 'ਘੰਟੇ'},
			M = {'ਮਿੰਟ', 'ਮਿੰਟ'},
			S = {'ਸਕਿੰਟ', 'ਸਕਿੰਟ'},
		},
		abbr_on = {
			y = 'y',
			m = 'm',
			w = 'w',
			d = 'd',
			H = 'h',
			M = 'm',
			S = 's',
		},
		abbr_infant = {      -- for {{age for infant}}
			sep = '&nbsp;',
			y = {'yr', 'yrs'},
			m = {'mo', 'mos'},
			w = {'wk', 'wks'},
			d = {'day', 'days'},
			H = {'hr', 'hrs'},
			M = {'min', 'mins'},
			S = {'sec', 'secs'},
		},
		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
		-- {{age_yd|20 Dec 2001|2003|range=yes}} → 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
				local y, m, d = fields[index], fields[index+1], fields[index+2]
				if (m == 2 or m == '2') and (d == 29 or d == '29') then
					-- Workaround error with following which attempt to use invalid date 2001-02-29.
					-- {{age_ymwd|year1=2001|year2=2004|month2=2|day2=29}}
					-- {{age_ymwd|year1=2001|month1=2|year2=2004|month2=1|day2=29}}
					-- TODO Get rid of wantMixture because even this ugly code does not handle
					-- 'Feb' or 'February' or 'feb' or 'february'.
					if not ((y % 4 == 0 and y % 100 ~= 0) or y % 400 == 0) then
						d = 28
					end
				end
				dates[i] = Date(y, m, d)
			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 = {                -- {{age in days}}
			show = 'd',
			disp = 'disp_raw',
		},
		age_days_nts = {            -- {{age in days nts}}
			show = 'd',
			disp = 'disp_raw',
			format = 'format_commas',
			sortable = 'on',
		},
		duration_days = {           -- {{duration in days}}
			show = 'd',
			disp = 'disp_raw',
			duration = true,
		},
		duration_days_nts = {       -- {{duration in days nts}}
			show = 'd',
			disp = 'disp_raw',
			format = 'format_commas',
			sortable = 'on',
			duration = true,
		},
		age_full_years = {          -- {{age}}
			show = 'y',
			abbr = 'abbr_raw',
			flag = 'usesCurrent',
			omitZero = true,
			range = 'no',
		},
		age_full_years_nts = {      -- {{age nts}}
			show = 'y',
			abbr = 'abbr_raw',
			format = 'format_commas',
			sortable = 'on',
		},
		age_in_years = {            -- {{age in years}}
			show = 'y',
			abbr = 'abbr_raw',
			negative = 'error',
			range = 'dash',
		},
		age_in_years_nts = {        -- {{age in years nts}}
			show = 'y',
			abbr = 'abbr_raw',
			negative = 'error',
			range = 'dash',
			format = 'format_commas',
			sortable = 'on',
		},
		age_infant = {              -- {{age for 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 = {                   -- {{age in months}}
			show = 'm',
			disp = 'disp_raw',
		},
		age_w = {                   -- {{age in weeks}}
			show = 'w',
			disp = 'disp_raw',
		},
		age_wd = {                  -- {{age in weeks and days}}
			show = 'wd',
		},
		age_yd = {                  -- {{age in years and days}}
			show = 'yd',
			format = 'format_commas',
			sep = args.sep ~= 'ਅਤੇ' and 'sep_comma' or nil,
		},
		age_yd_nts = {              -- {{age in years and days nts}}
			show = 'yd',
			format = 'format_commas',
			sep = args.sep ~= 'ਅਤੇ' and 'sep_comma' or nil,
			sortable = 'on',
		},
		age_ym = {                  -- {{age in years and months}}
			show = 'ym',
			sep = 'sep_comma',
		},
		age_ymd = {                 -- {{age in years, months and days}}
			show = 'ymd',
			range = true,
		},
		age_ymwd = {                -- {{age in years, months, weeks and days}}
			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 = mtext['txt-bda-disp']
	local show = '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 result = substituteParameters(
		mtext['txt-bda'],
		date:text('%-Y-%m-%d'),
		from_en(date:text(dateFormat(args))),
		from_en(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)
		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 fmt_date, fmt_ymd
	if date1.day then  -- y, m, d known
		fmt_date = dateFormat(args)
		fmt_ymd = '%-Y-%m-%d'
	elseif date1.month then  -- y, m known; d unknown
		fmt_date = '%B %-Y'
		fmt_ymd = '%-Y-%m-00'
	else  -- y known; m, d unknown
		fmt_date = '%-Y'
		fmt_ymd = '%-Y-00-00'
	end
	local sortKey
	local sortable = translateParameters.sortable[args.sortable]
	if sortable then
		local value = (date1.partial and date1.partial.first or date1).jdz
		sortKey = makeSort(value, sortable)
	end
	local result = (sortKey or '') .. substituteParameters(
		mtext['txt-dda'],
		date1:text(fmt_ymd),
		from_en(date1:text(fmt_date)),
		from_en(dateDifference({
			diff = diff,
			show = 'y',
			abbr = 'abbr_off',
			disp = mtext['txt-dda-disp'],
			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)
		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
}