Module:Currency
Documentation for this module may be created at Module:Currency/doc
require('Module:No globals')
local p = {}
local lang = mw.language.getContentLanguage(); -- language object for this wiki
local presentation ={}; -- table of tables that contain currency presentation data
local properties;
--[[--------------------------< I S _ S E T >------------------------------------------------------------------
Whether variable is set or not. A variable is set when it is not nil and not empty.
]]
local function is_set( var )
return not (var == nil or var == '');
end
--[[--------------------------< M A K E _ S H O R T _ F O R M _ N A M E >-------------------------------------
Assembles value and symbol according to the order specified in the properties table for this currency code
]]
local function make_short_form_name (amount, code, linked)
local symbol;
local position = properties[code].position;
if linked then
symbol = string.format ('[[%s|%s]]', properties[code].page, properties[code].symbol); -- make wikilink of page and symbol
else
symbol = properties[code].symbol;
end
amount = lang:formatNum (tonumber(amount)); -- add appropriate comma separators
amount = amount:gsub ('^%-', '−'); -- replace the hyphen with unicode minus
if 'b' == position then -- choose appropriate format: unspaced before the amount
return string.format ('%s%s', symbol, amount);
elseif 'bs' == position then -- spaced before the amount
return string.format ('%s %s', symbol, amount);
elseif 'a' == position then -- unspaced after the amount
return string.format ('%s%s', amount, symbol);
elseif 'as' == position then -- spaced after the amount
return string.format ('%s %s', amount, symbol);
elseif 'd' == position then -- special case that replaces the decimal separator with symbol (Cifrão for CVE is the only extant case)
local digits, decimals; -- this code may not work for other currencies or on other language wikis
if amount:match ('[%d,]+%.%d+') then -- with decimal separator and decimals
digits, decimals = amount:match ('([%d,]+)%.(%d+)')
amount = string.format ('%s%s%s', digits, symbol, decimals); -- insert symbol
elseif amount:match ('[%d,]+%.?$') then -- with or without decimal separator
digits = amount:match ('([%d,]+)%.?$')
amount = string.format ('%s%s00', digits, symbol); -- add symbol and 00 ($00)
end
amount = amount:gsub (',', '%.'); -- replace grouping character with period
return amount;
end
return amount .. ' <span style="font-size:inherit" class="error">{{currency}} – definition missing position ([[Template:Currency/doc#Error_messages|help]])</span>'; -- position not defined
end
--[[--------------------------< M A K E _ N A M E >----------------------------------------------------------
Make a wikilink from the currency's article title and its plural (if provided). If linked is false, returns only
the article title (unlinked)
]]
local function make_name (linked, page, plural)
if not linked then
if not is_set (plural) then
return page; -- just the page
elseif 's' == plural then -- if the simple plural form
return string.format ('%ss', page); -- append an 's'
else
return plural; -- must be the complex plural form (pounds sterling v. dollars)
end
else
if not is_set (plural) then
return string.format ('[[%s]]', page);
elseif 's' == plural then -- if the simple plural form
return string.format ('[[%s]]s', page);
else
return string.format ('[[%s|%s]]', page, plural); -- must be the complex plural form (pounds sterling v. dollars)
end
end
end
--[[--------------------------< M A K E _ L O N G _ F O R M _ N A M E >---------------------------------------
assembles a long-form currency name from amount and name from the properties tables; plural for all values not equal to 1
]]
local function make_long_form_name (amount, code, linked)
local name;
if not is_set (properties[code].page) then
return '<span style="font-size:inherit" class="error">{{currency}} – definition missing page ([[Template:Currency/doc#Error_messages|help]])</span>';
end
amount = tonumber (amount); -- make sure it's a number
if 1 == amount then
name = make_name (linked, properties[code].page); -- the singular form
elseif is_set (properties[code].plural) then -- plural and there is a plural form
name = make_name (linked, properties[code].page, properties[code].plural);
else
name = make_name (linked, properties[code].page); -- plural but no separate plural form so use the singular form
end
return string.format ('%s %s', lang:formatNum (amount), name); -- put it all together
end
--[[--------------------------< R E N D E R _ C U R R E N C Y >------------------------------------------------
Renders currency amount with symbol or long-form name.
Also, entry point for other modules. Assumes that parameters have been vetted; amount is a number, code is upper
case string, long_form is boolean; all are required.
]]
local function render_currency (amount, code, long_form, linked)
local name;
presentation = mw.loadData ('Module:Currency/Presentation'); -- get presentation data
if presentation.currency_properties[code] then -- if code is an iso 4217 code
properties = presentation.currency_properties;
elseif presentation.code_translation[code] then -- not iso 4217 but can be translated
code = presentation.code_translation[code]; -- then translate
properties = presentation.currency_properties;
elseif presentation.non_standard_properties[code] then -- last chance, is it a non-standard code?
properties = presentation.non_standard_properties;
else
return '<span style="font-size:inherit" class="error">{{currency}} – invalid code ([[Template:Currency/doc#Error_messages|help]])</span>';
end
if long_form then
return make_long_form_name (amount, code, linked); --
else
return make_short_form_name (amount, code, linked);
end
end
--[[--------------------------< P A R S E _ F O R M A T T E D _ N U M B E R >----------------------------------
replacement for lang:parseFormattedNumber() which doesn't work; all it does is strip commas.
This function returns a string where all comma separators have been removed from the source string. If the source
is malformed: has characters other than digits, commas, and decimal points; has too many decimal points; has commas
in in appropriate locations; then the function returns nil.
]]
local function parse_formatted_number (amount)
local count;
local parts = {};
local digits = {};
local decimals;
local sign = '';
local _;
if amount:find ('[^%-−%d%.,]') then -- anything but sign, digits, decimal points, or commas
return nil;
end
amount = amount:gsub ('−', '-'); -- replace unicode minus with hyphen
_, count = amount:gsub('%.', '') -- count the number of decimal point characters
if 1 < count then
return nil; -- too many dots
end
_, count = amount:gsub(',', '') -- count the number of grouping characters
if 0 == count then
return amount; -- no comma separators so we're done
end;
if amount:match ('[%-][%d%.,]+') then -- if the amount is negative
sign, amount = amount:match ('([%-])([%d%.,]+)'); -- strip off and save the sign
end
parts = mw.text.split (amount, '.', true); -- split amount into digits and decimals
decimals = table.remove (parts, 2) or ''; -- if there was a decimal portion, remove from the table and save it
digits = mw.text.split (parts[1], ',') -- split amount into groups
for i, v in ipairs (digits) do -- loop through the groups
if 1 == i then -- left-most digit group
if (3 < v:len() or not is_set (v)) then -- first digit group: 1, 2, 3 digits; can't be empty string (first char was a comma)
return nil;
end
else
if v and 3 ~= v:len() then -- all other groups must be three digits long
return nil;
end
end
end
return sign .. table.concat (digits) .. '.' .. decimals; -- reassemble without commas and return
end
--[[--------------------------< C O N V E R T _ S T R I N G _ T O _ N U M E R I C >------------------------------------------------
Converts quantified number/string combinations to a number e.g. 1 thousand to 1000.
]]
local function convert_string_to_numeric (amount)
local quantifiers = {['thousand'] = 1000, ['million'] = 1000000, ['m'] = 1000000, ['billion'] = 1000000000, ['b'] = 1000000000, ['trillion'] = 1000000000000};
local n, q = amount:match ('([%-−]?[%d%.,]+)%s*(%a+)$'); -- see if there is a quantifier following a number; zero or more space characters
if nil == n then
n, q = amount:match ('([%-−]?[%d%.,]+) (%a+)$') -- see if there is a quantifier following a number; nbsp html entity ({{format price}} output
end
if nil == n then return amount end; -- if not <number><space><quantifier> return amount unmolested
n = n:gsub (',', ''); -- strip comma separators if present
q = q:lower(); -- set the quantifier to lower case
if nil == quantifiers[q] then return amount end; -- if not a recognized quantifier
return tostring (n * quantifiers[q]); -- return a string, not a number
end
--[[--------------------------< C U R R E N C Y >--------------------------------------------------------------
Template:Currency entry point. The template takes three parameters:
positional (1st), |amount=, |Amount= : digits and decimal points only
positional (2nd), |type=, |Type= : code that identifies the currency
|first= : uses currency name instead of symbol
]]
local function currency (frame)
local args = require('Module:Arguments').getArgs (frame);
local amount, code;
local long_form = false;
local linked = true;
if not is_set (args[1]) then
return '<span style="font-size:inherit" class="error">{{currency}} – invalid amount ([[Template:Currency/doc#Error_messages|help]])</span>';
end
-- amount = lang:parseFormattedNumber(args[1]); -- if args[1] can't be converted to a number then error (this just strips grouping characters)
-- if args[1]:find ('[^%d%.]') or not amount then -- non-digit characters or more than one decimal point (because lag:parse... is broken)
-- return '<span style="font-size:inherit" class="error">{{currency}} – invalid amount ([[Template:Currency/doc#Error_messages|help]])</span>';
-- end
amount = convert_string_to_numeric (args[1]);
amount = parse_formatted_number(amount); -- if args[1] can't be converted to a number then error
if not amount then
return '<span style="font-size:inherit" class="error">{{currency}} – invalid amount ([[Template:Currency/doc#Error_messages|help]])</span>';
end
if not is_set(args[2]) then -- if not provided
code = 'USD'; -- default to USD
else
code = args[2]:upper(); -- always upper case; used as index into data tables which all use upper case
end
if args[3] then -- this is the |first= parameter TODO: make this value meaningful? y, yes, true?
long_form = true;
end
if 'no' == args[4] then -- this is the |linked= parameter; defaults to 'yes'; any value but 'no' means yes
linked = false;
end
return render_currency (amount, code, long_form, linked)
end
return {
currency = currency, -- template entry point
_render_currency = render_currency, -- other modules entry point
}