Module:Formatnum
This module provides a number formatting function. This function can be used from #invoke or from other Lua modules.
This module is used by Module:Complex date
Use from other Lua modules
To use the module from normal wiki pages, no special preparation is needed. If you are using the module from another Lua module, first you need to load it, like this:
<syntaxhighlight lang="lua"> local mf = require('Module:Formatnum') </syntaxhighlight>
(The mf variable stands for Module Formatnum; you can choose something more descriptive if you prefer.)
Most functions in the module have a version for Lua and a version for #invoke. It is possible to use the #invoke functions from other Lua modules, but using the Lua functions has the advantage that you do not need to access a Lua frame object. Lua functions are preceded by _, whereas #invoke functions are not.
main
{{#invoke:Formatnum|main|x|lang=|prec=|sep=}}
<syntaxhighlight lang="lua"> mf.formatNum(x, lang, prec, sep) </syntaxhighlight>
See also
-- This module is intended to replace the functionality of Template:Formatnum and related templates.
local p = {}
function p.main(frame)
local args = frame:getParent().args
local prec = args.prec or ''
local sep = args.sep or ''
local number = args[1] or args.number or ''
local lang = args[2] or args.lang or ''
-- validate the language parameter within MediaWiki's caller frame
if lang == "arabic-indic" then -- only for back-compatibility ("arabic-indic" is not a SupportedLanguage)
lang = "fa" -- better support than "ks"
elseif lang == '' or not mw.language.isSupportedLanguage(lang) then
-- Note that 'SupportedLanguages' are not necessarily 'BuiltinValidCodes', and so they are not necessarily
-- 'KnownLanguages' (with a language name defined at least in the default localisation of the local wiki).
-- But they all are ValidLanguageCodes (suitable as Wiki subpages or identifiers: no slash, colon, HTML tags, or entities)
-- In addition, they do not contain any capital letter in order to be unique in page titles (restriction inexistant in BCP47),
-- but they may violate the standard format of BCP47 language tags for specific needs in MediaWiki.
-- Empty/unspecified and unsupported languages are treated here in Commons using the user's language,
-- instead of the local 'ContentLanguage' of the Wiki.
lang = frame:callParserFunction( "int", "lang" ) -- get user's chosen language
end
return p.formatNum(number, lang, prec, sep ~= '')
end
local digit = { -- substitution of decimal digits for languages not supported by mw.language:formatNum() in core Lua libraries for MediaWiki
["ml-old"] = { '൦', '൧', '൨', '൩', '൪', '൫', '൬', '൭', '൮', '൯' },
["mn"] = { '᠐', '᠑', '᠒', '᠓', '᠔', '᠕', '᠖', '᠗', '᠘', '᠙'},
["ta"] = { '௦', '௧', '௨', '௩', '௪', '௫', '௬', '௭', '௮', '௯'},
["te"] = { '౦', '౧', '౨', '౩', '౪', '౫', '౬', '౭', '౮', '౯'},
["th"] = { '๐', '๑', '๒', '๓', '๔', '๕', '๖', '๗', '๘', '๙'}
}
function p.formatNum(number, lang, prec, compact)
-- Do not alter the specified value when it is not a valid number, return it as is
local value = tonumber(number)
if value == nil then
return number
end
-- Basic ASCII-only formatting (without paddings)
number = tostring(value)
-- Check the presence of an exponent (incorrectly managed in mw.language:FormatNum() and even forgotten due to an internal bug, e.g. in Hindi)
local exponent
local pos = string.find(number, '[Ee]')
if pos ~= nil then
exponent = string.sub(number, pos + 1, string.len(number))
number = string.sub(number, 1, pos - 1)
else
exponent = ''
end
-- Check the minimum precision requested
prec = tonumber(prec) -- nil if not specified as a true number
if prec ~= nil then
prec = math.floor(prec)
if prec < 0 then
prec = nil -- discard an incorrect precision (not a positive integer)
elseif prec > 14 then
prec = 14 -- maximum precision supported by tostring(number)
end
end
-- Preprocess the minimum precision in the ASCII string
local dot
if (prec or 0) > 0 then
pos = string.find(number, '.', 1, true) -- plain search, no regexp
if pos ~= nil then
prec = pos + prec - string.len(number) -- effective number of trailing decimals to add or remove
dot = '' -- already present
else
dot = '.' -- must be added
end
else
dot = '' -- don't add dot
prec = 0 -- don't alter the precision
end
if lang ~= nil and mw.language.isKnownLanguageTag(lang) == true then
-- Convert number to localized digits, decimal separator, and group separators
local language = mw.getLanguage(lang)
if compact then
number = language:formatNum(tonumber(number), { noCommafy = 'y' }) -- caveat: can load localized resources for up to 20 languages
else
number = language:formatNum(tonumber(number)) -- caveat: can load localized resources for up to 20 languages
end
-- Postprocessing the precision
if prec > 0 then
local zero = language:formatNum(0)
number = number .. dot .. mw.ustring.rep(zero, prec)
elseif prec < 0 then
-- TODO: rounding of last decimal; here only truncate decimals in excess
number = mw.ustring.sub(number, 1, mw.ustring.len(number) + prec)
end
-- Append the localized base-10 exponent without grouping separators (there's no reliable way to detect a localized leading symbol 'E')
if exponent ~= '' then
number = number .. 'E' .. language:formatNum(tonumber(exponent),{noCommafy=true})
end
else -- not localized, ASCII only
-- Postprocessing the precision
if prec > 0 then
number = number .. dot .. mw.string.rep('0', prec)
elseif prec < 0 then
-- TODO: rounding of last decimal; here only truncate decimals in excess
number = mw.string.sub(number, 1, mw.string.len(number) + prec)
end
-- Append the base-10 exponent
if exponent ~= '' then
number = number .. 'E' .. exponent
end
end
-- Special cases for substitution of ASCII digits (missing support in Lua core libraries for some languages)
if digit[lang] then
for i, v in ipairs(digit[lang]) do
number = mw.ustring.gsub(number, tostring(i - 1), v)
end
end
return number
end
return p