Mô đun:Convert

-- Convert a value from one unit of measurement to another.
-- Example: --> 123 pounds (56 kg)
-- See :en:Template:Convert/Transwiki guide if copying to another wiki.

local MINUS = '−' -- Unicode U+2212 MINUS SIGN (UTF-8: e2 88 92)
local abs = math.abs
local floor = math.floor
local format = string.format
local log10 = math.log10
local ustring = mw.ustring
local ulen = ustring.len
local usub = ustring.sub

-- Configuration options to keep magic values in one location.
-- Conversion data and message text are defined in separate modules.
local config, maxsigfig
local numdot -- must be '.' or ',' or a character which works in a regex
local numsep, numsep_remove, numsep_remove2
local data_code, all_units
local text_code
local varname -- can be a code to use variable names that depend on value
local from_en_table -- to translate an output string of en digits to local language
local to_en_table -- to translate an input string of digits in local language to en
-- Use translation_table in convert/text to change the following.
local en_default -- true uses lang=en unless convert has lang=local or local digits
local group_method = 3 -- code for how many digits are in a group
local per_word = 'per' -- for units like "liters per kilometer"
local plural_suffix = 's' -- only other useful value is probably to disable plural unit names
local omitsep -- true to omit separator before local symbol/name

-- All units should be defined in the data module. However, to cater for quick changes
-- and experiments, any unknown unit is looked up in an extra data module, if it exists.
-- That module would be transcluded in only a small number of pages, so there should be
-- little server overhead from making changes, and changes should propagate quickly.
local extra_module -- name of module with extra units
local extra_units -- nil or table of extra units from extra_module

-- Some options in the invoking template can set variables used later in the module.
local currency_text -- for a user-defined currency symbol: (euro replaces dollar)

local function from_en(text)
-- Input is a string representing a number in en digits with '.' decimal mark,
-- without digit grouping (which is done just after calling this).
-- Return the translation of the string with numdot and digits in local language.
if numdot ~= '.' then
text = text:gsub('%.', numdot)
end
if from_en_table then
text = text:gsub('%d', from_en_table)
end
return text
end

local function to_en(text)
-- Input is a string representing a number in the local language with
-- an optional numdot decimal mark and numsep digit grouping.
-- Return the translation of the string with '.' mark and en digits,
-- and no separators (they have to be removed here to handle cases like
-- numsep = '.' and numdot = ',' with input "1.234.567,8").
if to_en_table then
text = ustring.gsub(text, '%d', to_en_table)
end
if numsep_remove then
text = text:gsub(numsep_remove, )
end
if numsep_remove2 then
text = text:gsub(numsep_remove2, )
end
if numdot ~= '.' then
text = text:gsub(numdot, '.')
end
return text
end

local function decimal_mark(text)
-- Return ',' if text probably is using comma for decimal mark, or has no decimal mark.
-- Return '.' if text probably is using dot for decimal mark.
-- Otherwise return nothing (decimal mark not known).
if not text:find('[.,]') then return ',' end
text = text:gsub('^%-', ):gsub('%+%d+/%d+$', ):gsub('[Ee]%-?%d+$', )
local decimal =
text:match('^0?([.,])%d+$') or
text:match('%d([.,])%d?%d?$') or
text:match('%d([.,])%d%d%d%d+$')
if decimal then return decimal end
if text:match('%.%d+%.') then return ',' end
if text:match('%,%d+,') then return '.' end
end

local add_warning, with_separator -- forward declarations
local function to_en_with_check(text, parms)
-- Version of to_en() for a wiki using numdot = ',' and numsep = '.' to check
-- text (an input number as a string) which might have been copied from enwiki.
-- For example, in '1.234' the '.' could be a decimal mark or a group separator.
-- From viwiki.
if to_en_table then
text = ustring.gsub(text, '%d', to_en_table)
end
if decimal_mark(text) == '.' then
local original = text
text = text:gsub(',', ) -- for example, interpret "1,234.5" as an enwiki value
if parms then
add_warning(parms, 0, 'cvt_enwiki_num', original, with_separator({}, text))
end
else
if numsep_remove then
text = text:gsub(numsep_remove, )
end
if numsep_remove2 then
text = text:gsub(numsep_remove2, )
end
if numdot ~= '.' then
text = text:gsub(numdot, '.')
end
end
return text
end

local function omit_separator(id)
-- Return true if there should be no separator before id (a unit symbol or name).
-- For zhwiki, there should be no separator if id uses local characters.
-- The following kludge should be a sufficient test.
if omitsep then
if id:sub(1, 2) == '-{' then -- for "-{...}-" content language variant
return true
end
if id:byte() > 127 then
local first = usub(id, 1, 1)
if first ~= 'Å' and first ~= '°' and first ~= 'µ' then
return true
end
end
end
return id:sub(1, 1) == '/' -- no separator before units like "/ha"
end

local spell_module -- name of module that can spell numbers
local speller -- function from that module to handle spelling (set if needed)
local wikidata_module, wikidata_data_module -- names of Wikidata modules
local wikidata_code, wikidata_data -- exported tables from those modules (set if needed)

local function set_config(args)
-- Set configuration options from template invoke or defaults.
config = args
maxsigfig = config.maxsigfig or 14 -- maximum number of significant figures
local data_module, text_module
local sandbox = config.sandbox and ('/' .. config.sandbox) or
data_module = "Module:Convert/data" .. sandbox
text_module = "Module:Convert/text" .. sandbox
extra_module = "Module:Convert/extra" .. sandbox
wikidata_module = "Module:Convert/wikidata" .. sandbox
wikidata_data_module = "Module:Convert/wikidata/data" .. sandbox
spell_module = "Module:ConvertNumeric"
data_code = mw.loadData(data_module)
text_code = mw.loadData(text_module)
all_units = data_code.all_units
local translation = text_code.translation_table
if translation then
numdot = translation.numdot
numsep = translation.numsep
if numdot ',' and numsep '.' then
if text_code.all_messages.cvt_enwiki_num then
to_en = to_en_with_check
end
end
if translation.group then
group_method = translation.group
end
if translation.per_word then
per_word = translation.per_word
end
if translation.plural_suffix then
plural_suffix = translation.plural_suffix
end
varname = translation.varname
from_en_table = translation.from_en
local use_workaround = true
if use_workaround then
-- 2013-07-05 workaround bug by making a copy of the required table.
-- mw.ustring.gsub fails with a table (to_en_table) as the replacement,
-- if the table is accessed via mw.loadData.
local source = translation.to_en
if source then
to_en_table = {}
for k, v in pairs(source) do
to_en_table[k] = v
end
end
else
to_en_table = translation.to_en
end
if translation.lang == 'en default' then
en_default = true -- for hiwiki
end
omitsep = translation.omitsep -- for zhwiki
end
numdot = config.numdot or numdot or '.' -- decimal mark before fractional digits
numsep = config.numsep or numsep or ',' -- group separator for numbers
-- numsep should be ',' or '.' or or '&nbsp;' or a Unicode character.
-- numsep_remove must work in a regex to identify separators to be removed.
if numsep ~= then
numsep_remove = (numsep == '.') and '%.' or numsep
end
if numsep ~= ',' and numdot ~= ',' then
numsep_remove2 = ',' -- so numbers copied from enwiki will work
end
end

local function collection()
-- Return a table to hold items.
return {
n = 0,
add = function (self, item)
self.n = self.n + 1
self[self.n] = item
end,
}
end

local function divide(numerator, denominator)
-- Return integers quotient, remainder resulting from dividing the two
-- given numbers, which should be unsigned integers.
local quotient, remainder = floor(numerator / denominator), numerator % denominator
if not (0 limit then
s = usub(s, 1, limit)
append = '...'
end
s = mw.text.nowiki(s) .. (append or )
else
s = '?'
end
parts['$' .. i] = s
end
local function ispreview()
-- Return true if a prominent message should be shown.
if parms.test 'preview' or parms.test 'nopreview' then
-- For testing, can preview a real message or simulate a preview
-- when running automated tests.
return parms.test == 'preview'
end
local success, revid = pcall(function ()
return (parms.frame):preprocess() end)
return success and (revid == )
end
local want_warning = is_warning and
not config.warnings and -- show unobtrusive warnings if config.warnings not configured
not msg.nowarn -- but use msg settings, not standard warning, if specified
local title = string.gsub(msg[1] or 'Missing message', '$%d+', parts)
local text = want_warning and '' or msg[2] or 'Missing message'
local cat = wanted_category(msg[3], mcode[2], want_warning)
local anchor = msg[4] or
local fmtkey = ispreview() and 'cvt_format_preview' or
(want_warning and 'cvt_format2' or msg.format or 'cvt_format')
local fmt = text_code.all_messages[fmtkey] or 'convert: bug'
return subparm(fmt, title:gsub('"', '&quot;'), text, cat, anchor)
end
return 'Convert internal error: unknown message'
end

function add_warning(parms, level, key, text1, text2) -- for forward declaration above
-- If enabled, add a warning that will be displayed after the convert result.
-- A higher level is more verbose: more kinds of warnings are displayed.
-- To reduce output noise, only the first warning is displayed.
if level 60 then
a = 60
end
return mach_table[a + 4] 0.44704 -- mph converted to m/s
end
-- END: Code required only for built-in units.
------------------------------------------------------------------------

local function add_style(parms, class)
-- Add selected template style to parms if not already present.
parms.templatestyles = parms.templatestyles or {}
if not parms.templatestyles[class] then
parms.templatestyles[class] = parms.frame:extensionTag({
name = 'templatestyles', args = { src = text_code.titles[class] }
})
end
end

local function get_styles(parms)
-- Return string of required template styles, empty if none.
if parms.templatestyles then
local t = {}
for _, v in pairs(parms.templatestyles) do
table.insert(t, v)
end
return table.concat(t)
end
return
end

local function get_range(word)
-- Return a range (string or table) corresponding to word (like "to"),
-- or return nil if not a range word.
local ranges = text_code.ranges
return ranges.types[word] or ranges.types[ranges.aliases[word]]
end

local function check_mismatch(unit1, unit2)
-- If unit1 cannot be converted to unit2, return an error message table.
-- This allows conversion between units of the same type, and between
-- Nm (normally torque) and ftlb (energy), as in gun-related articles.
-- This works because Nm is the base unit (scale = 1) for both the
-- primary type (torque), and the alternate type (energy, where Nm = J).
-- A match occurs if the primary types are the same, or if unit1 matches
-- the alternate type of unit2, and vice versa. That provides a whitelist
-- of which conversions are permitted between normally incompatible types.
if unit1.utype unit2.utype or
(unit1.utype unit2.alttype and unit1.alttype == unit2.utype) then
return nil
end
return { 'cvt_mismatch', unit1.utype, unit2.utype }
end

local function override_from(out_table, in_table, fields)
-- Copy the specified fields from in_table to out_table, but do not
-- copy nil fields (keep any corresponding field in out_table).
for _, field in ipairs(fields) do
if in_table[field] then
out_table[field] = in_table[field]
end
end
end

local function shallow_copy(t)
-- Return a shallow copy of table t.
-- Do not need the features and overhead of the Scribunto mw.clone().
local result = {}
for k, v in pairs(t) do
result[k] = v
end
return result
end

local unit_mt = {
-- Metatable to get missing values for a unit that does not accept SI prefixes.
-- Warning: The boolean value 'false' is returned for any missing field
-- so __index is not called twice for the same field in a given unit.
__index = function (self, key)
local value
if key 'name1' or key 'sym_us' then
value = self.symbol
elseif key == 'name2' then
value = self.name1 .. plural_suffix
elseif key == 'name1_us' then
value = self.name1
if not rawget(self, 'name2_us') then
-- If name1_us is 'foot', do not make name2_us by appending plural_suffix.
self.name2_us = self.name2
end
elseif key == 'name2_us' then
local raw1_us = rawget(self, 'name1_us')
if raw1_us then
value = raw1_us .. plural_suffix
else
value = self.name2
end
elseif key == 'link' then
value = self.name1
else
value = false
end
rawset(self, key, value)
return value
end
}

local function prefixed_name(unit, name, index)
-- Return unit name with SI prefix inserted at correct position.
-- index = 1 (name1), 2 (name2), 3 (name1_us), 4 (name2_us).
-- The position is a byte (not character) index, so use Lua's sub().
local pos = rawget(unit, 'prefix_position')
if type(pos) == 'string' then
pos = tonumber(split(pos, ',')[index])
end
if pos then
return name:sub(1, pos - 1) .. unit.si_name .. name:sub(pos)
end
return unit.si_name .. name
end

local unit_prefixed_mt = {
-- Metatable to get missing values for a unit that accepts SI prefixes.
-- Before use, fields si_name, si_prefix must be defined.
-- The unit must define _symbol, _name1 and
-- may define _sym_us, _name1_us, _name2_us
-- (_sym_us, _name2_us may be defined for a language using sp=us
-- to refer to a variant unrelated to U.S. units).
__index = function (self, key)
local value
if key == 'symbol' then
value = self.si_prefix .. self._symbol
elseif key == 'sym_us' then
value = rawget(self, '_sym_us')
if value then
value = self.si_prefix .. value
else
value = self.symbol
end
elseif key == 'name1' then
value = prefixed_name(self, self._name1, 1)
elseif key == 'name2' then
value = rawget(self, '_name2')
if value then
value = prefixed_name(self, value, 2)
else
value = self.name1 .. plural_suffix
end
elseif key == 'name1_us' then
value = rawget(self, '_name1_us')
if value then
value = prefixed_name(self, value, 3)
else
value = self.name1
end
elseif key == 'name2_us' then
value = rawget(self, '_name2_us')
if value then
value = prefixed_name(self, value, 4)
elseif rawget(self, '_name1_us') then
value = self.name1_us .. plural_suffix
else
value = self.name2
end
elseif key == 'link' then
value = self.name1
else
value = false
end
rawset(self, key, value)
return value
end
}

local unit_per_mt = {
-- Metatable to get values for a per unit of form "x/y".
-- This is never called to determine a unit name or link because per units
-- are handled as a special case.
-- Similarly, the default output is handled elsewhere, and for a symbol
-- this is only called from get_default() for default_exceptions.
__index = function (self, key)
local value
if key == 'symbol' then
local per = self.per
local unit1, unit2 = per[1], per[2]
if unit1 then
value = unit1[key] .. '/' .. unit2[key]
else
value = '/' .. unit2[key]
end
elseif key == 'sym_us' then
value = self.symbol
elseif key == 'scale' then
local per = self.per
local unit1, unit2 = per[1], per[2]
value = (unit1 and unit1.scale or 1) self.scalemultiplier / unit2.scale
else
value = false
end
rawset(self, key, value)
return value
end
}

local function make_per(unitcode, unit_table, ulookup)
-- Return true, t where t is a per unit with unit codes expanded to unit tables,
-- or return false, t where t is an error message table.
local result = {
unitcode = unitcode,
utype = unit_table.utype,
per = {}
}
override_from(result, unit_table, { 'invert', 'iscomplex', 'default', 'link', 'symbol', 'symlink' })
result.symbol_raw = (result.symbol or false) -- to distinguish between a defined exception and a metatable calculation
local prefix
for i, v in ipairs(unit_table.per) do
if i 1 and v then
-- First unit symbol can be empty; that gives a nil first unit table.
elseif i == 1 and text_code.currency[v] then
prefix = currency_text or v
else
local success, t = ulookup(v)
if not success then return false, t end
result.per[i] = t
end
end
local multiplier = unit_table.multiplier
if not result.utype then
-- Creating an automatic per unit.
local unit1 = result.per[1]
local utype = (unit1 and unit1.utype or prefix or ) .. '/' .. result.per[2].utype
local t = data_code.per_unit_fixups[utype]
if t then
if type(t) == 'table' then
utype = t.utype or utype
result.link = result.link or t.link
multiplier = multiplier or t.multiplier
else
utype = t
end
end
result.utype = utype
end
result.scalemultiplier = multiplier or 1
result.vprefix = prefix or false -- set to non-nil to avoid calling __index
return true, setmetatable(result, unit_per_mt)
end

local function lookup(parms, unitcode, what, utable, fails, depth)
-- Return true, t where t is a copy of the unit's converter table,
-- or return false, t where t is an error message table.
-- Parameter 'what' determines whether combination units are accepted:
-- 'no_combination' : single unit only
-- 'any_combination' : single unit or combination or output multiple
-- 'only_multiple' : single unit or output multiple only
-- Parameter unitcode is a symbol (like 'g'), with an optional SI prefix (like 'kg').
-- If, for example, 'kg' is in this table, that entry is used;
-- otherwise the prefix ('k') is applied to the base unit ('g').
-- If unitcode is a known combination code (and if allowed by what),
-- a table of output multiple unit tables is included in the result.
-- For compatibility with the old template, an underscore in a unitcode is
-- replaced with a space so usage like works.
-- Wikignomes may also put two spaces or "&nbsp;" in combinations, so
-- replace underscore, "&nbsp;", and multiple spaces with a single space.
utable = utable or parms.unittable or all_units
fails = fails or {}
depth = depth and depth + 1 or 1
if depth > 9 then
-- There are ways to mistakenly define units which result in infinite
-- recursion when lookup() is called. That gives a long delay and very
-- confusing error messages, so the depth parameter is used as a guard.
return false, { 'cvt_lookup', unitcode }
end
if unitcode nil or unitcode then
return false, { 'cvt_no_unit' }
end
unitcode = unitcode:gsub('_', ' '):gsub('&nbsp;', ' '):gsub(' +', ' ')
local function call_make_per(t)
return make_per(unitcode, t,
function (ucode) return lookup(parms, ucode, 'no_combination', utable, fails, depth) end
)
end
local t = utable[unitcode]
if t then
if t.shouldbe then
return false, { 'cvt_should_be', t.shouldbe }
end
if t.sp_us then
parms.opt_sp_us = true
end
local target = t.target -- nil, or unitcode is an alias for this target
if target then
local success, result = lookup(parms, target, what, utable, fails, depth)
if not success then return false, result end
override_from(result, t, { 'customary', 'default', 'link', 'symbol', 'symlink' })
local multiplier = t.multiplier
if multiplier then
result.multiplier = tostring(multiplier)
result.scale = result.scale multiplier
end
return true, result
end
if t.per then
return call_make_per(t)
end
local combo = t.combination -- nil or a table of unitcodes
if combo then
local multiple = t.multiple
if what 'no_combination' or (what 'only_multiple' and not multiple) then
return false, { 'cvt_bad_unit', unitcode }
end
-- Recursively create a combination table containing the
-- converter table of each unitcode.
local result = { utype = t.utype, multiple = multiple, combination = {} }
local cvt = result.combination
for i, v in ipairs(combo) do
local success, t = lookup(parms, v, multiple and 'no_combination' or 'only_multiple', utable, fails, depth)
if not success then return false, t end
cvt[i] = t
end
return true, result
end
local result = shallow_copy(t)
result.unitcode = unitcode
if result.prefixes then
result.si_name =
result.si_prefix =
return true, setmetatable(result, unit_prefixed_mt)
end
return true, setmetatable(result, unit_mt)
end
local SIprefixes = text_code.SIprefixes
for plen = SIprefixes[1] or 2, 1, -1 do
-- Look for an SI prefix; should never occur with an alias.
-- Check for longer prefix first ('dam' is decametre).
-- SIprefixes[1] = prefix maximum characters (as seen by mw.ustring.sub).
local prefix = usub(unitcode, 1, plen)
local si = SIprefixes[prefix]
if si then
local t = utable[usub(unitcode, plen+1)]
if t and t.prefixes then
local result = shallow_copy(t)
result.unitcode = unitcode
result.si_name = parms.opt_sp_us and si.name_us or si.name
result.si_prefix = si.prefix or prefix
result.scale = t.scale 10 ^ (si.exponent t.prefixes)
return true, setmetatable(result, unit_prefixed_mt)
end
end
end
-- Accept user-defined combinations like "acre+m2+ha" or "acre m2 ha" for output.
-- If '+' is used, each unit code can include a space, and any error is fatal.
-- If ' ' is used and if each space-separated word is a unit code, it is a combo,
-- but errors are not fatal so the unit code can be looked up as an extra unit.
local err_is_fatal
local combo = collection()
if unitcode:find('+', 1, true) then
err_is_fatal = true
for item in (unitcode .. '+'):gmatch('%s(.-)%s%+') do
if item ~= then
combo:add(item)
end
end
elseif unitcode:find('%s') then
for item in unitcode:gmatch('%S+') do
combo:add(item)
end
end
if combo.n > 1 then
local function lookup_combo()
if what 'no_combination' or what 'only_multiple' then
return false, { 'cvt_bad_unit', unitcode }
end
local result = { combination = {} }
local cvt = result.combination
for i, v in ipairs(combo) do
local success, t = lookup(parms, v, 'only_multiple', utable, fails, depth)
if not success then return false, t end
if i == 1 then
result.utype = t.utype
else
local mismatch = check_mismatch(result, t)
if mismatch then
return false, mismatch
end
end
cvt[i] = t
end
return true, result
end
local success, result = lookup_combo()
if success or err_is_fatal then
return success, result
end
end
-- Accept any unit with an engineering notation prefix like "e6cuft"
-- (million cubic feet), but not chained prefixes like "e3e6cuft",
-- and not if the unit is a combination or multiple,
-- and not if the unit has an offset or is a built-in.
-- Only en digits are accepted.
local exponent, baseunit = unitcode:match('^e(%d+)(.)')
if exponent then
local engscale = text_code.eng_scales[exponent]
if engscale then
local success, result = lookup(parms, baseunit, 'no_combination', utable, fails, depth)
if success and not (result.offset or result.builtin or result.engscale) then
result.unitcode = unitcode -- 'e6cuft' not 'cuft'
result.defkey = unitcode -- key to lookup default exception
result.engscale = engscale
result.scale = result.scale 10 ^ tonumber(exponent)
return true, result
end
end
end
-- Look for x/y; split on right-most slash to get scale correct (x/y/z is x/y per z).
local top, bottom = unitcode:match('^(.-)/([^/]+)$')
if top and not unitcode:find('e%d') then
-- If valid, create an automatic per unit for an "x/y" unit code.
-- The unitcode must not include extraneous spaces.
-- Engineering notation (apart from at start and which has been stripped before here),
-- is not supported so do not make a per unit if find text like 'e3' in unitcode.
local success, result = call_make_per({ per = {top, bottom} })
if success then
return true, result
end
end
if not parms.opt_ignore_error and not get_range(unitcode) then
-- Want the "what links here" list for the extra_module to show only cases
-- where an extra unit is used, so do not require it if invoked from
-- or if looking up a range word which cannot be a unit.
if not extra_units then
local success, extra = pcall(function () return require(extra_module).extra_units end)
if success and type(extra) == 'table' then
extra_units = extra
end
end
if extra_units then
-- A unit in one data table might refer to a unit in the other table, so
-- switch between them, relying on fails or depth to terminate loops.
if not fails[unitcode] then
fails[unitcode] = true
local other = (utable == all_units) and extra_units or all_units
local success, result = lookup(parms, unitcode, what, other, fails, depth)
if success then
return true, result
end
end
end
end
if to_en_table then
-- At fawiki it is common to translate all digits so a unit like "km2" becomes "km۲".
local en_code = ustring.gsub(unitcode, '%d', to_en_table)
if en_code ~= unitcode then
return lookup(parms, en_code, what, utable, fails, depth)
end
end
return false, { 'cvt_unknown', unitcode }
end

local function valid_number(num)
-- Return true if num is a valid number.
-- In Scribunto (different from some standard Lua), when expressed as a string,
-- overflow or other problems are indicated with text like "inf" or "nan"
-- which are regarded as invalid here (each contains "n").
if type(num) 'number' and tostring(num):find('n', 1, true) nil then
return true
end
end

local function hyphenated(name, parts)
-- Return a hyphenated form of given name (for adjectival usage).
-- The name may be linked and the target of the link must not be changed.
-- Hypothetical examples:
-- ton → ton (no change)
-- long ton → long-ton
-- long ton → long-ton
-- long ton → long-ton
-- Input can also have multiple links in a single name like:
-- U.S. gallon
-- miles per U.S. quart
-- long tons per short ton
-- Assume that links cannot be nested (never like "abc[[defghi]]").
-- This uses a simple and efficient procedure that works for most cases.
-- Some units (if used) would require more, and can later think about
-- adding a method to handle exceptions.
-- The procedure is to replace each space with a hyphen, but
-- not a space after ')' [for "(pre-1954&nbsp;US) nautical mile"], and
-- not spaces immediately before '(' or in '(...)' [for cases like
-- "British thermal unit (ISO)" and "Calorie (International Steam Table)"].
if name:find(' ', 1, true) then
if parts then
local pos
if name:sub(1, 1) == '(' then
pos = name:find(')', 1, true)
if pos then
return name:sub(1, pos+1) .. name:sub(pos+2):gsub(' ', '-')
end
elseif name:sub(-1) == ')' then
pos = name:find('(', 1, true)
if pos then
return name:sub(1, pos-2):gsub(' ', '-') .. name:sub(pos-1)
end
end
return name:gsub(' ', '-')
end
parts = collection()
for before, item, after in name:gmatch('([^[])(%[%[[^[]%]%])([^[])') do
if item:find(' ', 1, true) then
local prefix
local plen = item:find('|', 1, true)
if plen then
prefix = item:sub(1, plen)
item = item:sub(plen + 1, -3)
else
prefix = item:sub(1, -3) .. '|'
item = item:sub(3, -3)
end
item = prefix .. hyphenated(item, parts) .. ']]'
end
parts:add(before:gsub(' ', '-') .. item .. after:gsub(' ', '-'))
end
if parts.n == 0 then
-- No link like "..." was found in the original name.
parts:add(hyphenated(name, parts))
end
return table.concat(parts)
end
return name
end

local function hyphenated_maybe(parms, want_name, sep, id, inout)
-- Return s, f where
-- s = id, possibly modified
-- f = true if hyphenated
-- Possible modifications: hyphenate; prepend '-'; append mid text.
if id nil or id then
return
end
local mid = (inout == (parms.opt_flip and 'out' or 'in')) and parms.mid or
if want_name then
if parms.opt_adjectival then
return '-' .. hyphenated(id) .. mid, true
end
if parms.opt_add_s and id:sub(-1) ~= 's' then
id = id .. 's' -- for nowiki
end
end
return sep .. id .. mid
end

local function use_minus(text)
-- Return text with Unicode minus instead of '-', if present.
if text:sub(1, 1) == '-' then
return MINUS .. text:sub(2)
end
return text
end

local function digit_groups(parms, text, method)
-- Return a numbered table of groups of digits (left-to-right, in local language).
-- Parameter method is a number or nil:
-- 3 for 3-digit grouping (default), or
-- 2 for 3-then-2 grouping (only for digits before decimal mark).
local len_right
local len_left = text:find('.', 1, true)
if len_left then
len_right = text - len_left
len_left = len_left - 1
else
len_left = text
end
local twos = method == 2 and len_left > 5
local groups = collection()
local run = len_left
local n
if run 0 do
groups:add(n)
run = run - n
n = (twos and run > 3) and 2 or 3
end
if len_right then
if groups.n == 0 then
groups:add(0)
end
if parms.opt_gaps and len_right > 3 then
local want4 = not parms.opt_gaps3 -- true gives no gap before trailing single digit
local isfirst = true
run = len_right
while run > 0 do
n = (want4 and run == 4) and 4 or (run > 3 and 3 or run)
if isfirst then
isfirst = false
groups[groups.n] = groups[groups.n] + 1 + n
else
groups:add(n)
end
run = run - n
end
else
groups[groups.n] = groups[groups.n] + 1 + len_right
end
end
local pos = 1
for i, length in ipairs(groups) do
groups[i] = from_en(text:sub(pos, pos + length - 1))
pos = pos + length
end
return groups
end

function with_separator(parms, text) -- for forward declaration above
-- Input text is a number in en digits with optional '.' decimal mark.
-- Return an equivalent, formatted for display:
-- with a custom decimal mark instead of '.', if wanted
-- with thousand separators inserted, if wanted
-- digits in local language
-- The given text is like '123' or '123.' or '12345.6789'.
-- The text has no sign (caller inserts that later, if necessary).
-- When using gaps, they are inserted before and after the decimal mark.
-- Separators are inserted only before the decimal mark.
-- A trailing dot (as in '123.') is removed because their use appears to
-- be accidental, and such a number should be shown as '123' or '123.0'.
-- It is useful for convert to suppress the dot so, for example, '4000.'
-- is a simple way of indicating that all the digits are significant.
if text:sub(-1) == '.' then
text = text:sub(1, -2)
end
if text '
local gap =
local close =
return nowrap .. groups[1] .. gap .. table.concat(groups, close .. gap, 2, groups.n) .. close .. close
end
return table.concat(groups, numsep)
end

-- An input value like 1.23e12 is displayed using scientific notation (1.23×10¹²).
-- That also makes the output use scientific notation, except for small values.
-- In addition, very small or very large output values use scientific notation.
-- Use format(fmtpower, significand, '10', exponent) where each argument is a string.
local fmtpower = '%s×%s%s'

local function with_exponent(parms, show, exponent)
-- Return wikitext to display the implied value in scientific notation.
-- Input uses en digits; output uses digits in local language.
return format(fmtpower, with_separator(parms, show), from_en('10'), use_minus(from_en(tostring(exponent))))
end

local function make_sigfig(value, sigfig)
-- Return show, exponent that are equivalent to the result of
-- converting the number 'value' (where value >= 0) to a string,
-- rounded to 'sigfig' significant figures.
-- The returned items are:
-- show: a string of digits; no sign and no dot;
-- there is an implied dot before show.
-- exponent: a number (an integer) to shift the implied dot.
-- Resulting value = tonumber('.' .. show) 10^exponent.
-- Examples:
-- make_sigfig(23.456, 3) returns '235', 2 (.235 10^2).
-- make_sigfig(0.0023456, 3) returns '235', -2 (.235 10^-2).
-- make_sigfig(0, 3) returns '000', 1 (.000 10^1).
if sigfig maxsigfig then
sigfig = maxsigfig
end
if value == 0 then
return string.rep('0', sigfig), 1
end
local exp, fracpart = math.modf(log10(value))
if fracpart >= 0 then
fracpart = fracpart - 1
exp = exp + 1
end
local digits = format('%.0f', 10^(fracpart + sigfig))
if digits > sigfig then
-- Overflow (for sigfig=3: like 0.9999 rounding to "1000"; need "100").
digits = digits:sub(1, sigfig)
exp = exp + 1
end
assert(digits == sigfig, 'Bug: rounded number has wrong length')
return digits, exp
end

-- Fraction output format.
local fracfmt = {
{ -- Like (fraction slash).
'{SIGN}{NUM}&frasl;{DEN}', -- 1/2
'{SIGN}{WHOLE}+{NUM}&frasl;{DEN}', -- 1+2/3
style = 'frac',
},
{ -- Like (stacked fraction, that is, horizontal bar).
'{SIGN}{NUM}/{DEN}', -- 1//2
'{SIGN}{WHOLE}+{NUM}/{DEN}', -- 1+2//3
style = 'sfrac',
},
}

local function format_fraction(parms, inout, negative, wholestr, numstr, denstr, do_spell, style)
-- Return wikitext for a fraction, possibly spelled.
-- Inputs use en digits and have no sign; output uses digits in local language.
local wikitext
if not style then
style = parms.opt_fraction_horizontal and 2 or 1
end
if wholestr == then
wholestr = nil
end
local substitute = {
SIGN = negative and MINUS or ,
WHOLE = wholestr and with_separator(parms, wholestr),
NUM = from_en(numstr),
DEN = from_en(denstr),
}
wikitext = fracfmt[style][wholestr and 2 or 1]:gsub('{(%u+)}', substitute)
if do_spell then
if negative then
if wholestr then
wholestr = '-' .. wholestr
else
numstr = '-' .. numstr
end
end
local s = spell_number(parms, inout, wholestr, numstr, denstr)
if s then
return s
end
end
add_style(parms, fracfmt[style].style)
return wikitext
end

local function format_number(parms, show, exponent, isnegative)
-- Parameter show is a string or a table containing strings.
-- Each string is a formatted number in en digits and optional '.' decimal mark.
-- A table represents a fraction: integer, numerator, denominator;
-- if a table is given, exponent must be nil.
-- Return t where t is a table with fields:
-- show = wikitext formatted to display implied value
-- (digits in local language)
-- is_scientific = true if show uses scientific notation
-- clean = unformatted show (possibly adjusted and with inserted '.')
-- (en digits)
-- sign = or MINUS
-- exponent = exponent (possibly adjusted)
-- The clean and exponent fields can be used to calculate the
-- rounded absolute value, if needed.
--
-- The value implied by the arguments is found from:
-- exponent is nil; and
-- show is a string of digits (no sign), with an optional dot;
-- show = '123.4' is value 123.4, '1234' is value 1234.0;
-- or:
-- exponent is an integer indicating where dot should be;
-- show is a string of digits (no sign and no dot);
-- there is an implied dot before show;
-- show does not start with '0';
-- show = '1234', exponent = 3 is value 0.123410^3 = 123.4.
--
-- The formatted result:
-- Is for an output value and is spelled if wanted and possible.
-- Includes a Unicode minus if isnegative and not spelled.
-- Uses a custom decimal mark, if wanted.
-- Has digits grouped where necessary, if wanted.
-- Uses scientific notation if requested, or for very small or large values
-- (which forces result to not be spelled).
-- Has no more than maxsigfig significant digits
-- (same as old template and ).
local xhi, xlo -- these control when scientific notation (exponent) is used
if parms.opt_scientific then
xhi, xlo = 4, 2 -- default for output if input uses e-notation
elseif parms.opt_scientific_always then
xhi, xlo = 0, 0 -- always use scientific notation (experimental)
else
xhi, xlo = 10, 4 -- default
end
local sign = isnegative and MINUS or
local maxlen = maxsigfig
local tfrac
if type(show) == 'table' then
tfrac = show
show = tfrac.wholestr
assert(exponent == nil, 'Bug: exponent given with fraction')
end
if not tfrac and not exponent then
local integer, dot, decimals = show:match('^(%d)(%.?)(.)')
if integer '0' or integer then
local zeros, figs = decimals:match('^(0)([^0]?.)')
if figs == 0 then
if zeros > maxlen then
show = '0.' .. zeros:sub(1, maxlen)
end
elseif zeros >= xlo then
show = figs
exponent = -zeros
elseif figs > maxlen then
show = '0.' .. zeros .. figs:sub(1, maxlen)
end
elseif integer >= xhi then
show = integer .. decimals
exponent = integer
else
maxlen = maxlen + dot
if show > maxlen then
show = show:sub(1, maxlen)
end
end
end
if exponent then
local function zeros(n)
return string.rep('0', n)
end
if show > maxlen then
show = show:sub(1, maxlen)
end
if exponent > xhi or exponent = 1e9 or value 1 then
significand = show:sub(1, 1) .. '.' .. show:sub(2)
else
significand = show
end
return {
clean = '.' .. show,
exponent = exponent,
sign = sign,
show = sign .. with_exponent(parms, significand, exponent-1),
is_scientific = true,
}
end
if exponent >= show then
show = show .. zeros(exponent - show) -- result has no dot
elseif exponent 2 then style = 2 end
local wikitext = format_fraction(parms, 'in', negative, leading_plus .. wholestr, numstr, denstr, parms.opt_spell_in, style)
return value, altvalue, wikitext, denominator
end

local function extract_number(parms, text, another, no_fraction)
-- Return true, info if can extract a number from text,
-- where info is a table with the result,
-- or return false, t where t is an error message table.
-- Input can use en digits or digits in local language and can
-- have references at the end. Accepting references is intended
-- for use in infoboxes with a field for a value passed to convert.
-- Parameter another = true if the expected value is not the first.
-- Before processing, the input text is cleaned:
-- Any thousand separators (valid or not) are removed.
-- Any sign is replaced with '-' (if negative) or (otherwise).
-- That replaces Unicode minus with '-'.
-- If successful, the returned info table contains named fields:
-- value = a valid number
-- altvalue = a valid number, usually same as value but different
-- if fraction used (for hands unit)
-- singular = true if value is 1 or -1 (to use singular form of units)
-- clean = cleaned text with any separators and sign removed
-- (en digits and '.' decimal mark)
-- show = text formatted for output, possibly with ref strip markers
-- (digits in local language and custom decimal mark)
-- The resulting show:
-- Is for an input value and is spelled if wanted and possible.
-- Has a rounded value, if wanted.
-- Has digits grouped where necessary, if wanted.
-- If negative, a Unicode minus is used; otherwise the sign is
-- '+' (if the input text used '+'), or is (if no sign in input).
text = strip(text or )
local reference
local pos = text:find('\127', 1, true)
if pos then
local before = text:sub(1, pos - 1)
local remainder = text:sub(pos)
local refs = {}
while remainder > 0 do
local ref, spaces
ref, spaces, remainder = remainder:match('^(\127[^\127]UNIQ[^\127]%-ref[^\127]\127)(%s)(.)')
if ref then
table.insert(refs, ref)
else
refs = {}
break
end
end
if refs > 0 then
text = strip(before)
reference = table.concat(refs)
end
end
local clean = to_en(text, parms)
if clean == then
return false, { another and 'cvt_no_num2' or 'cvt_no_num' }
end
local isnegative, propersign = false, -- most common case
local singular, show, denominator
local value = tonumber(clean)
local altvalue
if value then
local sign = clean:sub(1, 1)
if sign '+' or sign '-' then
propersign = (sign == '+') and '+' or MINUS
clean = clean:sub(2)
end
if value = 0.
-- If the input uses e-notation, show will be displayed using a power of ten, but
-- we use the number as given so it might not be normalized scientific notation.
-- The input value is spelled if specified so any e-notation is ignored;
-- that allows input like 2e6 to be spelled as "two million" which works
-- because the spell module converts '2e6' to '2000000' before spelling.
local function rounded(value, default, exponent)
local precision = parms.opt_ri
if precision then
local fmt = '%.' .. format('%d', precision) .. 'f'
local result = fmt:format(tonumber(value) + 2e-14) -- fudge for some common cases of bad rounding
if not exponent then
singular = (tonumber(result) == 1)
end
return result
end
return default
end
singular = (value == 1)
local scientific
local significand, exponent = clean:match('^([%d.]+)[Ee]([+%-]?%d+)')
if significand then
show = with_exponent(parms, rounded(significand, significand, exponent), exponent)
scientific = true
else
show = with_separator(parms, rounded(value, clean))
end
show = propersign .. show
if parms.opt_spell_in then
show = spell_number(parms, 'in', propersign .. rounded(value, clean)) or show
scientific = false
end
if scientific then
parms.opt_scientific = true
end
end
if isnegative and (value ~= 0) then
value = -value
altvalue = -(altvalue or value)
end
return true, {
value = value,
altvalue = altvalue or value,
singular = singular,
clean = clean,
show = show .. (reference or ),
denominator = denominator,
}
end

local function get_number(text)
-- Return v, f where:
-- v = nil (text is not a number)
-- or
-- v = value of text (text is a number)
-- f = true if value is an integer
-- Input can use en digits or digits in local language,
-- but no separators, no Unicode minus, and no fraction.
if text then
local number = tonumber(to_en(text))
if number then
local _, fracpart = math.modf(number)
return number, (fracpart == 0)
end
end
end

local function gcd(a, b)
-- Return the greatest common denominator for the given values,
-- which are known to be positive integers.
if a > b then
a, b = b, a
end
if a 1e8 then
return format('%.2f', value)
end
local integer, decimals = math.modf(value)
local numerator = floor((decimals denominator) +
0.5 + 2e-14) -- add fudge for some common cases of bad rounding
if numerator >= denominator then
integer = integer + 1
numerator = 0
end
local wholestr = tostring(integer)
if numerator > 0 then
local div = gcd(numerator, denominator)
if div > 1 then
numerator = numerator / div
denominator = denominator / div
end
return {
wholestr = (integer > 0) and wholestr or ,
numstr = tostring(numerator),
denstr = tostring(denominator),
value = value,
}
end
return wholestr
end

local function preunits(count, preunit1, preunit2)
-- If count is 1:
-- ignore preunit2
-- return p1
-- else:
-- preunit1 is used for preunit2 if the latter is empty
-- return p1, p2
-- where:
-- p1 is text to insert before the input unit
-- p2 is text to insert before the output unit
-- p1 or p2 may be nil to mean "no preunit"
-- Using '+' gives output like "5+ feet" (no space before, but space after).
local function withspace(text, wantboth)
-- Return text with space before and, if wantboth, after.
-- However, no space is added if there is a space or '&nbsp;' or '-'
-- at that position ('-' is for adjectival text).
-- There is also no space if text starts with '&'
-- (e.g. '&deg;' would display a degree symbol with no preceding space).
local char = text:sub(1, 1)
if char '&' then
return text -- an html entity can be used to specify the exact display
end
if not (char ' ' or char '-' or char '+') then
text = ' ' .. text
end
if wantboth then
char = text:sub(-1, -1)
if not (char ' ' or char '-' or text:sub(-6, -1) == '&nbsp;') then
text = text .. ' '
end
end
return text
end
local PLUS = '+ '
preunit1 = preunit1 or
local trim1 = strip(preunit1)
if count 1 then
if trim1 then
return nil
end
if trim1 == '+' then
return PLUS
end
return withspace(preunit1, true)
end
preunit1 = withspace(preunit1)
preunit2 = preunit2 or
local trim2 = strip(preunit2)
if trim1 '+' then
if trim2 or trim2 == '+' then
return PLUS, PLUS
end
preunit1 = PLUS
end
if trim2 then
if trim1 then
return nil, nil
end
preunit2 = preunit1
elseif trim2 == '+' then
preunit2 = PLUS
elseif trim2 == '&32;' then -- trick to make preunit2 empty
preunit2 = nil
else
preunit2 = withspace(preunit2)
end
return preunit1, preunit2
end

local function range_text(range, want_name, parms, before, after, inout)
-- Return before .. rtext .. after
-- where rtext is the text that separates two values in a range.
local rtext, adj_text, exception
if type(range) == 'table' then
-- Table must specify range text for ('off' and 'on') or ('input' and 'output'),
-- and may specify range text for 'adj=on',
-- and may specify exception = true.
rtext = range[want_name and 'off' or 'on'] or
range[((inout 'in') (parms.opt_flip == true)) and 'output' or 'input']
adj_text = range['adj']
exception = range['exception']
else
rtext = range
end
if parms.opt_adjectival then
if want_name or (exception and parms.abbr_org == 'on') then
rtext = adj_text or rtext:gsub(' ', '-'):gsub('&nbsp;', '-')
end
end
if rtext '–' and after:sub(1, MINUS) MINUS then
rtext = '&nbsp;– '
end
return before .. rtext .. after
end

local function get_composite(parms, iparm, in_unit_table)
-- Look for a composite input unit. For example,
-- would result in a call to this function with
-- iparm = 3 (parms[iparm] = "2", just after the first unit)
-- in_unit_table = (unit table for "yd"; contains value 1 for number of yards)
-- Return true, iparm, unit where
-- iparm = index just after the composite units (7 in above example)
-- unit = composite unit table holding all input units,
-- or return true if no composite unit is present in parms,
-- or return false, t where t is an error message table.
local default, subinfo
local composite_units, count = { in_unit_table }, 1
local fixups = {}
local total = in_unit_table.valinfo[1].value
local subunit = in_unit_table
while subunit.subdivs do -- subdivs is nil or a table of allowed subdivisions
local subcode = strip(parms[iparm+1])
local subdiv = subunit.subdivs[subcode] or subunit.subdivs[(all_units[subcode] or {}).target]
if not subdiv then
break
end
local success
success, subunit = lookup(parms, subcode, 'no_combination')
if not success then return false, subunit end -- should never occur
success, subinfo = extract_number(parms, parms[iparm])
if not success then return false, subinfo end
iparm = iparm + 2
subunit.inout = 'in'
subunit.valinfo = { subinfo }
-- Recalculate total as a number of subdivisions.
-- subdiv[1] = number of subdivisions per previous unit (integer > 1).
total = total subdiv[1] + subinfo.value
if not default then -- set by the first subdiv with a default defined
default = subdiv.default
end
count = count + 1
composite_units[count] = subunit
if subdiv.unit or subdiv.name then
fixups[count] = { unit = subdiv.unit, name = subdiv.name, valinfo = subunit.valinfo }
end
end
if count == 1 then
return true -- no error and no composite unit
end
for i, fixup in pairs(fixups) do
local unit = fixup.unit
local name = fixup.name
if not unit or (count > 2 and name) then
composite_units[i].fixed_name = name
else
local success, alternate = lookup(parms, unit, 'no_combination')
if not success then return false, alternate end -- should never occur
alternate.inout = 'in'
alternate.valinfo = fixup.valinfo
composite_units[i] = alternate
end
end
return true, iparm, {
utype = in_unit_table.utype,
scale = subunit.scale, -- scale of last (least significant) unit
valinfo = { { value = total, clean = subinfo.clean, denominator = subinfo.denominator } },
composite = composite_units,
default = default or in_unit_table.default
}
end

local function translate_parms(parms, kv_pairs)
-- Update fields in parms by translating each key:value in kv_pairs to terms
-- used by this module (may involve translating from local language to English).
-- Also, checks are performed which may display warnings, if enabled.
-- Return true if successful or return false, t where t is an error message table.
currency_text = nil -- local testing can hold module in memory; must clear globals
local accept_any_text = {
input = true,
qid = true,
qual = true,
stylein = true,
styleout = true,
tracking = true,
}
if kv_pairs.adj and kv_pairs.sing then
-- For enwiki (before translation), warn if attempt to use adj and sing
-- as the latter is a deprecated alias for the former.
if kv_pairs.adj ~= kv_pairs.sing and kv_pairs.sing ~= then
add_warning(parms, 1, 'cvt_unknown_option', 'sing=' .. kv_pairs.sing)
end
kv_pairs.sing = nil
end
kv_pairs.comma = kv_pairs.comma or config.comma -- for plwiki who want default comma=5
for loc_name, loc_value in pairs(kv_pairs) do
local en_name = text_code.en_option_name[loc_name]
if en_name then
local en_value
if en_name '$' or en_name 'frac' or en_name 'sigfig' then
if loc_value then
add_warning(parms, 2, 'cvt_empty_option', loc_name)
elseif en_name == '$' then
-- Value should be a single character like "€" for the euro currency symbol, but anything is accepted.
currency_text = (loc_value == 'euro') and '€' or loc_value
else
local minimum
local number, is_integer = get_number(loc_value)
if en_name == 'frac' then
minimum = 2
if number and number = minimum then
en_value = number
else
add_warning(parms, 1, (en_name == 'frac' and 'cvt_bad_frac' or 'cvt_bad_sigfig'), loc_name .. '=' .. loc_value)
end
end
elseif accept_any_text[en_name] then
en_value = loc_value ~= and loc_value or nil -- accept non-empty user text with no validation
if en_name == 'input' then
-- May have something like (empty input) if source is an infobox
-- with optional fields. In that case, want to output nothing rather than an error.
parms.input_text = loc_value -- keep input because parms.input is nil if loc_value ==
end
else
en_value = text_code.en_option_value[en_name][loc_value]
if en_value and en_value:sub(-1) == '?' then
en_value = en_value:sub(1, -2)
add_warning(parms, -1, 'cvt_deprecated', loc_name .. '=' .. loc_value)
end
if en_value nil then
if loc_value then
add_warning(parms, 2, 'cvt_empty_option', loc_name)
else
add_warning(parms, 1, 'cvt_unknown_option', loc_name .. '=' .. loc_value)
end
elseif en_value == then
en_value = nil -- an ignored option like adj=off
elseif type(en_value) 'string' and en_value:sub(1, 4) 'opt_' then
for _, v in ipairs(split(en_value, ',')) do
local lhs, rhs = v:match('^(.-)=(.+)$')
if rhs then
parms[lhs] = tonumber(rhs) or rhs
else
parms[v] = true
end
end
en_value = nil
end
end
parms[en_name] = en_value
else
add_warning(parms, 1, 'cvt_unknown_option', loc_name .. '=' .. loc_value)
end
end
local abbr_entered = parms.abbr
local cfg_abbr = config.abbr
if cfg_abbr then
-- Don't warn if invalid because every convert would show that warning.
if cfg_abbr == 'on always' then
parms.abbr = 'on'
elseif cfg_abbr == 'off always' then
parms.abbr = 'off'
elseif parms.abbr nil then
if cfg_abbr 'on default' then
parms.abbr = 'on'
elseif cfg_abbr == 'off default' then
parms.abbr = 'off'
end
end
end
if parms.abbr then
if parms.abbr == 'unit' then
parms.abbr = 'on'
parms.number_word = true
end
parms.abbr_org = parms.abbr -- original abbr, before any flip
elseif parms.opt_hand_hh then
parms.abbr_org = 'on'
parms.abbr = 'on'
else
parms.abbr = 'out' -- default is to abbreviate output only (use symbol, not name)
end
if parms.opt_order_out then
-- Disable options that do not work in a useful way with order=out.
parms.opt_flip = nil -- override adj=flip
parms.opt_spell_in = nil
parms.opt_spell_out = nil
parms.opt_spell_upper = nil
end
if parms.opt_spell_out and not abbr_entered then
parms.abbr = 'off' -- should show unit name when spelling the output value
end
if parms.opt_flip then
local function swap_in_out(option)
local value = parms[option]
if value == 'in' then
parms[option] = 'out'
elseif value == 'out' then
parms[option] = 'in'
end
end
swap_in_out('abbr')
swap_in_out('lk')
if parms.opt_spell_in and not parms.opt_spell_out then
-- For simplicity, and because it does not appear to be needed,
-- user cannot set an option to spell the output only.
parms.opt_spell_in = nil
parms.opt_spell_out = true
end
end
if parms.opt_spell_upper then
parms.spell_upper = parms.opt_flip and 'out' or 'in'
end
if parms.opt_table or parms.opt_tablecen then
if abbr_entered nil and parms.lk nil then
parms.opt_values = true
end
parms.table_align = parms.opt_table and 'right' or 'center'
end
if parms.table_align or parms.opt_sortable_on then
parms.need_table_or_sort = true
end
local disp_joins = text_code.disp_joins
local default_joins = disp_joins['b']
parms.join_between = default_joins[3] or '; '
local disp = parms.disp
if disp == nil then -- special case for the most common setting
parms.joins = default_joins
elseif disp == 'x' then
-- Later, parms.joins is set from the input parameters.
else
-- Old template does this.
local abbr = parms.abbr
if disp 'slash' then
if abbr_entered nil then
disp = 'slash-nbsp'
elseif abbr 'in' or abbr 'out' then
disp = 'slash-sp'
else
disp = 'slash-nosp'
end
elseif disp 'sqbr' then
if abbr 'on' then
disp = 'sqbr-nbsp'
else
disp = 'sqbr-sp'
end
end
parms.joins = disp_joins[disp] or default_joins
parms.join_between = parms.joins[3] or parms.join_between
parms.wantname = parms.joins.wantname
end
if (en_default and not parms.opt_lang_local and (parms[1] or ):find('%d')) or parms.opt_lang_en then
from_en_table = nil
end
if en_default and from_en_table then
-- For hiwiki: localized symbol/name is defined with the US symbol/name field,
-- and is used if output uses localized numbers.
parms.opt_sp_us = true
end
return true
end

local function get_values(parms)
-- If successful, update parms and return true, v, i where
-- v = table of input values
-- i = index to next entry in parms after those processed here
-- or return false, t where t is an error message table.
local valinfo = collection() -- numbered table of input values
local range = collection() -- numbered table of range items (having, for example, 2 range items requires 3 input values)
local had_nocomma -- true if removed "nocomma" kludge from second parameter (like "tonocomma")
local parm2 = strip(parms[2])
if parm2 and parm2:sub(-7, -1) == 'nocomma' then
parms[2] = strip(parm2:sub(1, -8))
parms.opt_nocomma = true
had_nocomma = true
end
local function extractor(i)
-- If the parameter is not a value, try unpacking it as a range ("1-23" for "1 to 23").
-- However, "-1-2/3" is a negative fraction (-1⅔), so it must be extracted first.
-- Do not unpack a parameter if it is like "3-1/2" which is sometimes incorrectly
-- used instead of "3+1/2" (and which should not be interpreted as "3 to ½").
-- Unpacked items are inserted into the parms table.
-- The tail recursion allows combinations like "1x2 to 3x4".
local valstr = strip(parms[i]) -- trim so any '-' as a negative sign will be at start
local success, result = extract_number(parms, valstr, i > 1)
if not success and valstr and i 0 then
if range.n > 30 then -- limit abuse, although 4 is a more likely upper limit
return false, { 'cvt_invalid_num' } -- misleading message but it will do
end
parms.range = range
elseif had_nocomma then
return false, { 'cvt_unknown', parm2 }
end
return true, valinfo, i
end

local function simple_get_values(parms)
-- If input is like "",
-- return true, i, in_unit, in_unit_table
-- i = index in parms of what follows valid_unit, if anything.
-- The valid_value is not negative and does not use a fraction, and
-- no options requiring further processing of the input are used.
-- Otherwise, return nothing or return false, parm1 for caller to interpret.
-- Testing shows this function is successful for 96% of converts in articles,
-- and that on average it speeds up converts by 8%.
local clean = to_en(strip(parms[1] or ), parms)
if parms.opt_ri or parms.opt_spell_in or clean > 10 or not clean:match('^[0-9.]+$') then
return false, clean
end
local value = tonumber(clean)
if not value then return end
local info = {
value = value,
altvalue = value,
singular = (value == 1),
clean = clean,
show = with_separator(parms, clean),
}
local in_unit = strip(parms[2])
local success, in_unit_table = lookup(parms, in_unit, 'no_combination')
if not success then return end
in_unit_table.valinfo = { info }
return true, 3, in_unit, in_unit_table
end

local function wikidata_call(parms, operation, ...)
-- Return true, s where s is the result of a Wikidata operation,
-- or return false, t where t is an error message table.
local function worker(...)
wikidata_code = wikidata_code or require(wikidata_module)
wikidata_data = wikidata_data or mw.loadData(wikidata_data_module)
return wikidata_code[operation](wikidata_data, ...)
end
local success, status, result = pcall(worker, ...)
if success then
return status, result
end
if parms.opt_sortable_debug then
-- Use debug=yes to crash if an error while accessing Wikidata.
error('Error accessing Wikidata: ' .. status, 0)
end
return false, { 'cvt_wd_fail' }
end

local function get_parms(parms, args)
-- If successful, update parms and return true, unit where
-- parms is a table of all arguments passed to the template
-- converted to named arguments, and
-- unit is the input unit table;
-- or return false, t where t is an error message table.
-- For special processing (not a convert), can also return
-- true, wikitext where wikitext is the final result.
-- The returned input unit table may be for a fake unit using the specified
-- unit code as the symbol and name, and with bad_mcode = message code table.
-- MediaWiki removes leading and trailing whitespace from the values of
-- named arguments. However, the values of numbered arguments include any
-- whitespace entered in the template, and whitespace is used by some
-- parameters (example: the numbered parameters associated with "disp=x").
local kv_pairs = {} -- table of input key:value pairs where key is a name; needed because cannot iterate parms and add new fields to it
for k, v in pairs(args) do
if type(k) 'number' or k 'test' then -- parameter "test" is reserved for testing and is not translated
parms[k] = v
else
kv_pairs[k] = v
end
end
if parms.test == 'wikidata' then
local ulookup = function (ucode)
-- Use empty table for parms so it does not accumulate results when used repeatedly.
return lookup({}, ucode, 'no_combination')
end
return wikidata_call(parms, '_listunits', ulookup)
end
local success, msg = translate_parms(parms, kv_pairs)
if not success then return false, msg end
if parms.input then
success, msg = wikidata_call(parms, '_adjustparameters', parms, 1)
if not success then return false, msg end
end
local success, i, in_unit, in_unit_table = simple_get_values(parms)
if not success then
if type(i) == 'string' and i:match('^NNN+$') then
-- Some infoboxes have examples like (3 or more "N").
-- Output an empty string for these.
return false, { 'cvt_no_output' }
end
local valinfo
success, valinfo, i = get_values(parms)
if not success then return false, valinfo end
in_unit = strip(parms[i])
i = i + 1
success, in_unit_table = lookup(parms, in_unit, 'no_combination')
if not success then
in_unit = in_unit or
if parms.opt_ignore_error then -- display given unit code with no error (for use with )
in_unit_table = -- suppress error message and prevent processing of output unit
end
in_unit_table = setmetatable({
symbol = in_unit, name2 = in_unit, utype = in_unit,
scale = 1, default = , defkey = , linkey = ,
bad_mcode = in_unit_table }, unit_mt)
end
in_unit_table.valinfo = valinfo
end
if parms.test 'msg' then
-- Am testing the messages produced when no output unit is specified, and
-- the input unit has a missing or invalid default.
-- Set two units for testing that.
-- LATER: Remove this code.
if in_unit 'chain' then
in_unit_table.default = nil -- no default
elseif in_unit == 'rd' then
in_unit_table.default = "ft!X!m" -- an invalid expression
end
end
in_unit_table.inout = 'in' -- this is an input unit
if not parms.range then
local success, inext, composite_unit = get_composite(parms, i, in_unit_table)
if not success then return false, inext end
if composite_unit then
in_unit_table = composite_unit
i = inext
end
end
if in_unit_table.builtin == 'mach' then
-- As with old template, a number following Mach as the input unit is the altitude,
-- and there is no way to specify an altitude for the output unit.
-- Could put more code in this function to get any output unit and check for
-- an altitude following that unit.
local success, info = extract_number(parms, parms[i], false, true)
if success then
i = i + 1
in_unit_table.altitude = info.value
end
end
local word = strip(parms[i])
i = i + 1
local precision, is_bad_precision
local function set_precision(text)
local number, is_integer = get_number(text)
if number then
if is_integer then
precision = number
else
precision = text
is_bad_precision = true
end
return true -- text was used for precision, good or bad
end
end
if word and not set_precision(word) then
parms.out_unit = parms.out_unit or word
if set_precision(strip(parms[i])) then
i = i + 1
end
end
if parms.opt_adj_mid then
word = parms[i]
i = i + 1
if word then -- mid-text words
if word:sub(1, 1) == '-' then
parms.mid = word
else
parms.mid = ' ' .. word
end
end
end
if parms.opt_one_preunit then
parms[parms.opt_flip and 'preunit2' or 'preunit1'] = preunits(1, parms[i])
i = i + 1
end
if parms.disp == 'x' then
-- Following is reasonably compatible with the old template.
local first = parms[i] or
local second = parms[i+1] or
i = i + 2
if strip(first) == then -- user can enter '&32;' rather than ' ' to avoid the default
first = ' [&nbsp;' .. first
second = '&nbsp;]' .. second
end
parms.joins = { first, second }
elseif parms.opt_two_preunits then
local p1, p2 = preunits(2, parms[i], parms[i+1])
i = i + 2
if parms.preunit1 then
-- To simplify documentation, allow unlikely use of adj=pre with disp=preunit
-- (however, an output unit must be specified with adj=pre and with disp=preunit).
parms.preunit1 = parms.preunit1 .. p1
parms.preunit2 = p2
else
parms.preunit1, parms.preunit2 = p1, p2
end
end
if precision == nil then
if set_precision(strip(parms[i])) then
i = i + 1
end
end
if is_bad_precision then
add_warning(parms, 1, 'cvt_bad_prec', precision)
else
parms.precision = precision
end
for j = i, i + 3 do
local parm = parms[j] -- warn if find a non-empty extraneous parameter
if parm and parm:match('%S') then
add_warning(parms, 1, 'cvt_unknown_option', parm)
break
end
end
return true, in_unit_table
end

local function record_default_precision(parms, out_current, precision)
-- If necessary, adjust parameters and return a possibly adjusted precision.
-- When converting a range of values where a default precision is required,
-- that default is calculated for each value because the result sometimes
-- depends on the precise input and output values. This function may cause
-- the entire convert process to be repeated in order to ensure that the
-- same default precision is used for each individual convert.
-- If that were not done, a range like 1000 to 1000.4 may give poor results
-- because the first output could be heavily rounded, while the second is not.
-- For range 1000.4 to 1000, this function can give the second convert the
-- same default precision that was used for the first.
if not parms.opt_round_each then
local maxdef = out_current.max_default_precision
if maxdef then
if maxdef 0 then
prec = math.max(log10(denominator), 1)
else
-- Count digits after decimal mark, handling cases like '12.345e6'.
local exponent
local integer, dot, decimals, expstr = inclean:match('^(%d)(%.?)(%d)(.)')
local e = expstr:sub(1, 1)
if e 'e' or e 'E' then
exponent = tonumber(expstr:sub(2))
end
if dot == then
prec = subunit_ignore_trailing_zero and 0 or -integer:match('0$'):len()
else
prec = decimals
end
if exponent then
-- So '1230' and '1.23e3' both give prec = -1, and '0.00123' and '1.23e-3' give 5.
prec = prec - exponent
end
end
if in_current.istemperature and out_current.istemperature then
-- Converting between common temperatures (°C, °F, °R, K); not keVT.
-- Kelvin value can be almost zero, or small but negative due to precision problems.
-- Also, an input value like -300 C (below absolute zero) gives negative kelvins.
-- Calculate minimum precision from absolute value.
adjust = 0
local kelvin = abs((invalue - in_current.offset) in_current.scale)
if kelvin 0 then
prefix = 7000 + mag
else
prefix = 2999 - mag
outvalue = outvalue + 10^(mag+1)
end
sortkey = format('%d', prefix) .. format('%015.0f', floor(outvalue 10^(14-mag)))
end
end
local sortspan
if sortkey and not parms.table_align then
sortspan = parms.opt_sortable_debug and
.. sortkey .. '♠' or

parms.join_before = sortspan
end
if parms.table_align then
local sort
if sortkey then
sort = ' data-sort-value="' .. sortkey .. '"'
if parms.opt_sortable_debug then
parms.join_before = .. sortkey ..
end
else
sort =
end
local style = 'style="text-align:' .. parms.table_align .. ';'
local joins = {}
for i = 1, 2 do
joins[i] = (i == 1 and or '\n|') .. style .. user_style(parms, i) .. '"' .. sort .. '|'
end
parms.table_joins = joins
end
return sortspan, scaled_value
end

local cvt_to_hand

local function cvtround(parms, info, in_current, out_current)
-- Return true, t where t is a table with the conversion results; fields:
-- show = rounded, formatted string with the result of converting value in info,
-- using the rounding specified in parms.
-- singular = true if result (after rounding and ignoring any negative sign)
-- is "1", or like "1.00", or is a fraction with value = 0 then
local fudge
if precision 1 then
frac = (precision == 2) and 2 or 4
end
local out_next = out_current.out_next
if out_next then
-- Use magic knowledge to determine whether the next unit is inches without requiring i18n.
-- The following ensures that when the output combination "hand in" is used, the inches
-- value is rounded to match the hands value. Also, displaying say "61½" instead of 61.5
-- is better as 61.5 implies the value is not 61.4.
if out_next.exception == 'subunit_more_precision' then
out_next.frac = frac
end
end
-- Convert to inches; calculate hands from that.
local dummy_unit_table = { scale = out_current.scale / 4, frac = frac }
local success, outinfo = cvtround(parms, info, in_current, dummy_unit_table)
if not success then return false, outinfo end
local tfrac = outinfo.fraction_table
local inches = outinfo.raw_absvalue
if tfrac then
inches = floor(inches) -- integer part only; fraction added later
else
inches = floor(inches + 0.5) -- a hands measurement never shows decimals of an inch
end
local hands, inches = divide(inches, 4)
outinfo.absvalue = hands + inches/4 -- supposed to be the absolute rounded value, but this is close enough
local inchstr = tostring(inches) -- '0', '1', '2' or '3'
if precision and precision ' or '>='
-- In addition, the following form is supported:
-- LHS and RHS
-- where
-- LHS, RHS = any of above expressions.
local function compare(value, text)
local arithop, factor, compop, limit = text:match('^%sv%s([]?)(.-)([<>]=?)(.)$')
if arithop nil then
error('Invalid default expression', 0)
elseif arithop '' then
factor = tonumber(factor)
if factor == nil then
error('Invalid default expression', 0)
end
value = value factor
end
limit = tonumber(limit)
if limit nil then
error('Invalid default expression', 0)
end
if compop then
return value > limit
elseif compop == '>=' then
return value >= limit
end
error('Invalid default expression', 0) -- should not occur
end
local lhs, rhs = condition:match('^(.-%W)and(%W.)')
if lhs == nil then
return compare(value, condition)
end
return compare(value, lhs) and compare(value, rhs)
end

local function get_default(value, unit_table)
-- Return true, s where s = name of unit's default output unit,
-- or return false, t where t is an error message table.
-- Some units have a default that depends on the input value
-- (the first value if a range of values is used).
-- If '!' is in the default, the first bang-delimited field is an
-- expression that uses 'v' to represent the input value.
-- Example: 'v mile
-- miles --> miles
-- However, just id is returned if:
-- no link given (so caller does not need to check if a link was defined); or
-- link has previously been used during the current convert (to avoid overlinking).
local link_key
if unit_table then
link_key = unit_table.unitcode or unit_table
else
link_key = link
end
if not link or link == or linked_pages[link_key] then
return id
end
linked_pages[link_key] = true
-- Following only works for language en, but it should be safe on other wikis,
-- and overhead of doing it generally does not seem worthwhile.
local l = link:sub(1, 1):lower() .. link:sub(2)
if link id or l id then
return .. id ..
elseif link .. 's' id or l .. 's' id then
return .. id:sub(1, -2) .. 's'
else
return .. id ..
end
end

local function variable_name(clean, unit_table)
-- For slwiki, a unit name depends on the value.
-- Parameter clean is the unsigned rounded value in en digits, as a string.
-- Value Source Example for "m"
-- integer 1: name1 meter (also is the name of the unit)
-- integer 2: var{1} metra
-- integer 3 and 4: var{2} metri
-- integer else: var{3} metrov (0 and 5 or more)
-- real/fraction: var{4} metra
-- var{i} means the i'th field in unit_table.varname if it exists and has
-- an i'th field, otherwise name2.
-- Fields are separated with "!" and are not empty.
-- A field for a unit using an SI prefix has the prefix name inserted,
-- replacing '' if found, or before the field otherwise.
local vname
if clean == '1' then
vname = unit_table.name1
elseif unit_table.varname then
local i
if clean == '2' then
i = 1
elseif clean '3' or clean '4' then
i = 2
elseif clean:find('.', 1, true) then
i = 4
else
i = 3
end
if i > 1 and varname == 'pl' then
i = i - 1
end
vname = split(unit_table.varname, '!')[i]
end
if vname then
local si_name = rawget(unit_table, 'si_name') or
local pos = vname:find('', 1, true)
if pos then
vname = vname:sub(1, pos - 1) .. si_name .. vname:sub(pos + 1)
else
vname = si_name .. vname
end
return vname
end
return unit_table.name2
end

local function linked_id(parms, unit_table, key_id, want_link, clean)
-- Return final unit id (symbol or name), optionally with a wikilink,
-- and update unit_table.sep if required.
-- key_id is one of: 'symbol', 'sym_us', 'name1', 'name1_us', 'name2', 'name2_us'.
local abbr_on = (key_id 'symbol' or key_id 'sym_us')
if abbr_on and want_link then
local symlink = rawget(unit_table, 'symlink')
if symlink then
return symlink -- for exceptions that have the linked symbol built-in
end
end
local multiplier = rawget(unit_table, 'multiplier')
local per = unit_table.per
if per then
local paren1, paren2 = , -- possible parentheses around bottom unit
local unit1 = per[1] -- top unit_table, or nil
local unit2 = per[2] -- bottom unit_table
if abbr_on then
if not unit1 then
unit_table.sep = -- no separator in "$2/acre"
end
if not want_link then
local symbol = unit_table.symbol_raw
if symbol then
return symbol -- for exceptions that have the symbol built-in
end
end
if (unit2.symbol):find('⋅', 1, true) then
paren1, paren2 = '(', ')'
end
end
local key_id2 -- unit2 is always singular
if key_id == 'name2' then
key_id2 = 'name1'
elseif key_id == 'name2_us' then
key_id2 = 'name1_us'
else
key_id2 = key_id
end
local result
if abbr_on then
result = '/'
elseif omitsep then
result = per_word
elseif unit1 then
result = ' ' .. per_word .. ' '
else
result = per_word .. ' '
end
if want_link and unit_table.link then
if abbr_on or not varname then
result = (unit1 and linked_id(parms, unit1, key_id, false, clean) or ) .. result .. linked_id(parms, unit2, key_id2, false, '1')
else
result = (unit1 and variable_name(clean, unit1) or ) .. result .. variable_name('1', unit2)
end
if omit_separator(result) then
unit_table.sep =
end
return make_link(unit_table.link, result, unit_table)
end
if unit1 then
result = linked_id(parms, unit1, key_id, want_link, clean) .. result
if unit1.sep then
unit_table.sep = unit1.sep
end
elseif omitsep then
unit_table.sep =
end
return result .. paren1 .. linked_id(parms, unit2, key_id2, want_link, '1') .. paren2
end
if multiplier then
-- A multiplier (like "100" in "100km") forces the unit to be plural.
multiplier = from_en(multiplier)
if not omitsep then
multiplier = multiplier .. (abbr_on and '&nbsp;' or ' ')
end
if not abbr_on then
if key_id == 'name1' then
key_id = 'name2'
elseif key_id == 'name1_us' then
key_id = 'name2_us'
end
end
else
multiplier =
end
local id = unit_table.fixed_name or ((varname and not abbr_on) and variable_name(clean, unit_table) or unit_table[key_id])
if omit_separator(id) then
unit_table.sep =
end
if want_link then
local link = data_code.link_exceptions[unit_table.linkey or unit_table.symbol] or unit_table.link
if link then
local before =
local i = unit_table.customary
if i == 1 and parms.opt_sp_us then
i = 2 -- show "U.S." not "US"
end
if i == 3 and abbr_on then
i = 4 -- abbreviate "imperial" to "imp"
end
local customary = text_code.customary_units[i]
if customary then
-- LATER: This works for language en only, but it's esoteric so ignore for now.
local pertext
if id:sub(1, 1) == '/' then
-- Want unit "/USgal" to display as "/U.S. gal", not "U.S. /gal".
pertext = '/'
id = id:sub(2)
elseif id:sub(1, 4) == 'per ' then
-- Similarly want "per U.S. gallon", not "U.S. per gallon" (but in practice this is unlikely to be used).
pertext = 'per '
id = id:sub(5)
else
pertext =
end
-- Omit any "US"/"U.S."/"imp"/"imperial" from start of id since that will be inserted.
local removes = (i ×' ..
from_en('10') ..
'^' ..
from_en(tostring(engscale.exponent)) ..
elseif number_word then
local number_id
local lk = parms.lk
if lk 'on' or lk inout then
number_id = make_link(engscale.link, engscale[1])
else
number_id = engscale[1]
end
-- :en:WP:NUMERAL recommends "&nbsp;" in values like "12 million".
info.show = info.show .. (parms.opt_adjectival and '-' or '&nbsp;') .. number_id
end
end
if prefix then
info.show = prefix .. info.show
end
end
end

local function process_input(parms, in_current)
-- Processing required once per conversion.
-- Return block of text to represent input (value/unit).
if parms.opt_output_only or parms.opt_output_number_only or parms.opt_output_unit_only then
parms.joins = { , }
return
end
local first_unit
local composite = in_current.composite -- nil or table of units
if composite then
first_unit = composite[1]
else
first_unit = in_current
end
local id1, want_name = make_id(parms, 1, first_unit)
local sep = first_unit.sep -- separator between value and unit, set by make_id
local preunit = parms.preunit1
if preunit then
sep = -- any separator is included in preunit
else
preunit =
end
if parms.opt_input_unit_only then
parms.joins = { , }
if composite then
local parts = { id1 }
for i, unit in ipairs(composite) do
if i > 1 then
table.insert(parts, (make_id(parms, 1, unit)))
end
end
id1 = table.concat(parts, ' ')
end
if want_name and parms.opt_adjectival then
return preunit .. hyphenated(id1)
end
return preunit .. id1
end
if parms.opt_also_symbol and not composite and not parms.opt_flip then
local join1 = parms.joins[1]
if join1 ' (' or join1 ' [' then
parms.joins = { ' [' .. first_unit[parms.opt_sp_us and 'sym_us' or 'symbol'] .. ']' .. join1 , parms.joins[2] }
end
end
if in_current.builtin == 'mach' and first_unit.sep ~= then -- means omitsep with non-enwiki name
local prefix = id1 .. '&nbsp;'
local range = parms.range
local valinfo = first_unit.valinfo
local result = prefix .. valinfo[1].show
if range then
-- For simplicity and because more not needed, handle one range item only.
local prefix2 = make_id(parms, 2, first_unit) .. '&nbsp;'
result = range_text(range[1], want_name, parms, result, prefix2 .. valinfo[2].show, 'in')
end
return preunit .. result
end
if composite then
-- Simplify: assume there is no range, and no decoration.
local mid = (not parms.opt_flip) and parms.mid or
local sep1 = '&nbsp;'
local sep2 = ' '
if parms.opt_adjectival and want_name then
sep1 = '-'
sep2 = '-'
end
if omitsep and sep == then
-- Testing the id of the most significant unit should be sufficient.
sep1 =
sep2 =
end
local parts = { first_unit.valinfo[1].show .. sep1 .. id1 }
for i, unit in ipairs(composite) do
if i > 1 then
table.insert(parts, unit.valinfo[1].show .. sep1 .. (make_id(parms, 1, unit)))
end
end
return table.concat(parts, sep2) .. mid
end
local add_unit = (parms.abbr == 'mos') or
parms[parms.opt_flip and 'out_range_x' or 'in_range_x'] or
(not want_name and parms.abbr_range_x)
local range = parms.range
if range and not add_unit then
unlink(first_unit)
end
local id = range and make_id(parms, range.n + 1, first_unit) or id1
local extra, was_hyphenated = hyphenated_maybe(parms, want_name, sep, id, 'in')
if was_hyphenated then
add_unit = false
end
local result
local valinfo = first_unit.valinfo
if range then
for i = 0, range.n do
local number_word
if i == range.n then
add_unit = false
number_word = true
end
decorate_value(parms, first_unit, i+1, number_word)
local show = valinfo[i+1].show
if add_unit then
show = show .. first_unit.sep .. (i 0 and id1 or make_id(parms, i+1, first_unit))
end
if i 0 then
result = show
else
result = range_text(range[i], want_name, parms, result, show, 'in')
end
end
else
decorate_value(parms, first_unit, 1, true)
result = valinfo[1].show
end
return result .. preunit .. extra
end

local function process_one_output(parms, out_current)
-- Processing required for each output unit.
-- Return block of text to represent output (value/unit).
local inout = out_current.inout -- normally 'out' but can be 'in' for order=out
local id1, want_name = make_id(parms, 1, out_current)
local sep = out_current.sep -- set by make_id
local preunit = parms.preunit2
if preunit then
sep = -- any separator is included in preunit
else
preunit =
end
if parms.opt_output_unit_only then
if want_name and parms.opt_adjectival then
return preunit .. hyphenated(id1)
end
return preunit .. id1
end
if out_current.builtin == 'mach' and out_current.sep ~= then -- means omitsep with non-enwiki name
local prefix = id1 .. '&nbsp;'
local range = parms.range
local valinfo = out_current.valinfo
local result = prefix .. valinfo[1].show
if range then
-- For simplicity and because more not needed, handle one range item only.
result = range_text(range[1], want_name, parms, result, prefix .. valinfo[2].show, inout)
end
return preunit .. result
end
local add_unit = (parms[parms.opt_flip and 'in_range_x' or 'out_range_x'] or
(not want_name and parms.abbr_range_x)) and
not parms.opt_output_number_only
local range = parms.range
if range and not add_unit then
unlink(out_current)
end
local id = range and make_id(parms, range.n + 1, out_current) or id1
local extra, was_hyphenated = hyphenated_maybe(parms, want_name, sep, id, inout)
if was_hyphenated then
add_unit = false
end
local result
local valinfo = out_current.valinfo
if range then
for i = 0, range.n do
local number_word
if i == range.n then
add_unit = false
number_word = true
end
decorate_value(parms, out_current, i+1, number_word)
local show = valinfo[i+1].show
if add_unit then
show = show .. out_current.sep .. (i 0 and id1 or make_id(parms, i+1, out_current))
end
if i 0 then
result = show
else
result = range_text(range[i], want_name, parms, result, show, inout)
end
end
else
decorate_value(parms, out_current, 1, true)
result = valinfo[1].show
end
if parms.opt_output_number_only then
return result
end
return result .. preunit .. extra
end

local function make_output_single(parms, in_unit_table, out_unit_table)
-- Return true, item where item = wikitext of the conversion result
-- for a single output (which is not a combination or a multiple);
-- or return false, t where t is an error message table.
if parms.opt_order_out and in_unit_table.unitcode == out_unit_table.unitcode then
out_unit_table.valinfo = in_unit_table.valinfo
else
out_unit_table.valinfo = collection()
for _, v in ipairs(in_unit_table.valinfo) do
local success, info = cvtround(parms, v, in_unit_table, out_unit_table)
if not success then return false, info end
out_unit_table.valinfo:add(info)
end
end
return true, process_one_output(parms, out_unit_table)
end

local function make_output_multiple(parms, in_unit_table, out_unit_table)
-- Return true, item where item = wikitext of the conversion result
-- for an output which is a multiple (like 'ftin');
-- or return false, t where t is an error message table.
local inout = out_unit_table.inout -- normally 'out' but can be 'in' for order=out
local multiple = out_unit_table.multiple -- table of scaling factors (will not be nil)
local combos = out_unit_table.combination -- table of unit tables (will not be nil)
local abbr = parms.abbr
local abbr_org = parms.abbr_org
local disp = parms.disp
local want_name = (abbr_org nil and (disp 'or' or disp 'slash')) or
not (abbr 'on' or abbr inout or abbr 'mos')
local want_link = (parms.lk 'on' or parms.lk inout)
local mid = parms.opt_flip and parms.mid or
local sep1 = '&nbsp;'
local sep2 = ' '
if parms.opt_adjectival and want_name then
sep1 = '-'
sep2 = '-'
end
local do_spell = parms.opt_spell_out
parms.opt_spell_out = nil -- so the call to cvtround does not spell the value
local function make_result(info, isfirst)
local fmt, outvalue, sign
local results = {}
for i = 1, combos do
local tfrac, thisvalue, strforce
local out_current = combos[i]
out_current.inout = inout
local scale = multiple[i]
if i == 1 then -- least significant unit ('in' from 'ftin')
local decimals
out_current.frac = out_unit_table.frac
local success, outinfo = cvtround(parms, info, in_unit_table, out_current)
if not success then return false, outinfo end
if isfirst then
out_unit_table.valinfo = { outinfo } -- in case output value of first least significant unit is needed
end
sign = outinfo.sign
tfrac = outinfo.fraction_table
if outinfo.is_scientific then
strforce = outinfo.show
decimals =
elseif tfrac then
decimals =
else
local show = outinfo.show -- number as a string in local language
local p1, p2 = show:find(numdot, 1, true)
decimals = p1 and show:sub(p2 + 1) or -- text after numdot, if any
end
fmt = '%.' .. ulen(decimals) .. 'f' -- to reproduce precision
if decimals == then
if tfrac then
outvalue = floor(outinfo.raw_absvalue) -- integer part only; fraction added later
else
outvalue = floor(outinfo.raw_absvalue + 0.5) -- keep all integer digits of least significant unit
end
else
outvalue = outinfo.absvalue
end
end
if scale then
outvalue, thisvalue = divide(outvalue, scale)
else
thisvalue = outvalue
end
local id
if want_name then
if varname then
local clean
if strforce or tfrac then
clean = '.1' -- dummy value to force name for floating point
else
clean = format(fmt, thisvalue)
end
id = variable_name(clean, out_current)
else
local key = 'name2'
if parms.opt_adjectival then
key = 'name1'
elseif tfrac then
if thisvalue == 0 then
key = 'name1'
end
elseif parms.opt_singular then
if 0 0) and tostring(thisvalue) or nil
strval = format_fraction(parms, spell_inout, false, wholestr, tfrac.numstr, tfrac.denstr, do_spell)
else
strval = (thisvalue == 0) and from_en('0') or with_separator(parms, format(fmt, thisvalue))
if do_spell then
strval = spell_number(parms, spell_inout, strval) or strval
end
end
table.insert(results, strval .. sep1 .. id)
if outvalue == 0 then
break
end
fmt = '%.0f' -- only least significant unit can have a non-integral value
end
local reversed, count = {}, results
for i = 1, count do
reversed[i] = results[count + 1 - i]
end
return true, sign .. table.concat(reversed, sep2)
end
local valinfo = in_unit_table.valinfo
local success, result = make_result(valinfo[1], true)
if not success then return false, result end
local range = parms.range
if range then
for i = 1, range.n do
local success, result2 = make_result(valinfo[i+1])
if not success then return false, result2 end
result = range_text(range[i], want_name, parms, result, result2, inout)
end
end
return true, result .. mid
end

local function process(parms, in_unit_table, out_unit_table)
-- Return true, s, outunit where s = final wikitext result,
-- or return false, t where t is an error message table.
linked_pages = {}
local success, bad_output
local bad_input_mcode = in_unit_table.bad_mcode -- nil if input unit is a valid convert unit
local out_unit = parms.out_unit
if out_unit nil or out_unit or type(out_unit) == 'function' then
if bad_input_mcode or parms.opt_input_unit_only then
bad_output =
else
local getdef = type(out_unit) == 'function' and out_unit or get_default
success, out_unit = getdef(in_unit_table.valinfo[1].value, in_unit_table)
parms.out_unit = out_unit
if not success then
bad_output = out_unit
end
end
end
if not bad_output and not out_unit_table then
success, out_unit_table = lookup(parms, out_unit, 'any_combination')
if success then
local mismatch = check_mismatch(in_unit_table, out_unit_table)
if mismatch then
bad_output = mismatch
end
else
bad_output = out_unit_table
end
end
local lhs, rhs
local flipped = parms.opt_flip and not bad_input_mcode
if bad_output then
rhs = (bad_output == ) and or message(parms, bad_output)
elseif parms.opt_input_unit_only then
rhs =
else
local combos -- nil (for 'ft' or 'ftin'), or table of unit tables (for 'm ft')
if not out_unit_table.multiple then -- nil/false ('ft' or 'm ft'), or table of factors ('ftin')
combos = out_unit_table.combination
end
local frac = parms.frac -- nil or denominator of fraction for output values
if frac then
-- Apply fraction to the unit (if only one), or to non-SI units (if a combination),
-- except that if a precision is also specified, the fraction only applies to
-- the hand unit; that allows the following result:
-- → 156 centimetres (61.4 in; 15.1½ hands)
-- However, the following is handled elsewhere as a special case:
-- → 156 centimetres (15.1½ hands; 61½ in)
if combos then
local precision = parms.precision
for _, unit in ipairs(combos) do
if unit.builtin == 'hand' or (not precision and not unit.prefixes) then
unit.frac = frac
end
end
else
out_unit_table.frac = frac
end
end
local outputs = {}
local imax = combos and combos or 1 -- 1 (single unit) or number of unit tables
if imax == 1 then
parms.opt_order_out = nil -- only useful with an output combination
end
if not flipped and not parms.opt_order_out then
-- Process left side first so any duplicate links (from lk=on) are suppressed
-- on right. Example:
lhs = process_input(parms, in_unit_table)
end
for i = 1, imax do
local success, item
local out_current = combos and combos[i] or out_unit_table
out_current.inout = 'out'
if i 1 then
if imax > 1 and out_current.builtin 'hand' then
out_current.out_next = combos[2] -- built-in hand can influence next unit in a combination
end
if parms.opt_order_out then
out_current.inout = 'in'
end
end
if out_current.multiple then
success, item = make_output_multiple(parms, in_unit_table, out_current)
else
success, item = make_output_single(parms, in_unit_table, out_current)
end
if not success then return false, item end
outputs[i] = item
end
if parms.opt_order_out then
lhs = outputs[1]
table.remove(outputs, 1)
end
local sep = parms.table_joins and parms.table_joins[2] or parms.join_between
rhs = table.concat(outputs, sep)
end
if flipped or not lhs then
local input = process_input(parms, in_unit_table)
if flipped then
lhs = rhs
rhs = input
else
lhs = input
end
end
if parms.join_before then
lhs = parms.join_before .. lhs
end
local wikitext
if bad_input_mcode then
if bad_input_mcode == then
wikitext = lhs
else
wikitext = lhs .. message(parms, bad_input_mcode)
end
elseif parms.table_joins then
wikitext = parms.table_joins[1] .. lhs .. parms.table_joins[2] .. rhs
else
wikitext = lhs .. parms.joins[1] .. rhs .. parms.joins[2]
end
if parms.warnings and not bad_input_mcode then
wikitext = wikitext .. parms.warnings
end
return true, get_styles(parms) .. wikitext, out_unit_table
end

local function main_convert(frame)
-- Do convert, and if needed, do it again with higher default precision.
local parms = { frame = frame } -- will hold template arguments, after translation
set_config(frame.args)
local success, result = get_parms(parms, frame:getParent().args)
if success then
if type(result) ~= 'table' then
return tostring(result)
end
local in_unit_table = result
local out_unit_table
for _ = 1, 2 do -- use counter so cannot get stuck repeating convert
success, result, out_unit_table = process(parms, in_unit_table, out_unit_table)
if success and parms.do_convert_again then
parms.do_convert_again = false
else
break
end
end
end
-- If input=x gives a problem, the result should be just the user input
-- (if x is a property like P123 it has been replaced with ).
-- An unknown input unit would display the input and an error message
-- with success true at this point.
-- Also, can have success false with a message that outputs an empty string.
if parms.input_text then
if success and not parms.have_problem then
return result
end
local cat
if parms.tracking then
-- Add a tracking category using the given text as the category sort key.
-- There is currently only one type of tracking, but in principle multiple
-- items could be tracked, using different sort keys for convenience.
cat = wanted_category('tracking', parms.tracking)
end
return parms.input_text .. (cat or )
end
return success and result or message(parms, result)
end

local function _unit(unitcode, options)
-- Helper function for Module:Val to look up a unit.
-- Parameter unitcode must be a string to identify the wanted unit.
-- Parameter options must be nil or a table with optional fields:
-- value = number (for sort key; default value is 1)
-- scaled_top = nil for a normal unit, or a number for a unit which is
-- the denominator of a per unit (for sort key)
-- si = { 'symbol', 'link' }
-- (a table with two strings) to make an SI unit
-- that will be used for the look up
-- link = true if result should be linked
-- sort = 'on' or 'debug' if result should include a sort key in a
-- span element ('debug' makes the key visible)
-- name = true for the name of the unit instead of the symbol
-- us = true for the US spelling of the unit, if any
-- Return nil if unitcode is not a non-empty string.
-- Otherwise return a table with fields:
-- text = requested symbol or name of unit, optionally linked
-- scaled_value = input value adjusted by unit scale; used for sort key
-- sortspan = span element with sort key like that provided by ,
-- calculated from the result of converting value
-- to a base unit with scale 1.
-- unknown = true if the unitcode was not known
unitcode = strip(unitcode)
if unitcode nil or unitcode then
return nil
end
set_config({})
linked_pages = {}
options = options or {}
local parms = {
abbr = options.name and 'off' or 'on',
lk = options.link and 'on' or nil,
opt_sp_us = options.us and true or nil,
opt_ignore_error = true, -- do not add pages using this function to 'what links here' for Module:Convert/extra
opt_sortable_on = options.sort 'on' or options.sort 'debug',
opt_sortable_debug = options.sort == 'debug',
}
if options.si then
-- Make a dummy table of units (just one unit) for lookup to use.
-- This makes lookup recognize any SI prefix in the unitcode.
local symbol = options.si[1] or '?'
parms.unittable = { [symbol] = {
_name1 = symbol,
_name2 = symbol,
_symbol = symbol,
utype = symbol,
scale = symbol == 'g' and 0.001 or 1,
prefixes = 1,
default = symbol,
link = options.si[2],
}}
end
local success, unit_table = lookup(parms, unitcode, 'no_combination')
if not success then
unit_table = setmetatable({
symbol = unitcode, name2 = unitcode, utype = unitcode,
scale = 1, default = , defkey = , linkey = }, unit_mt)
end
local value = tonumber(options.value) or 1
local clean = tostring(abs(value))
local info = {
value = value,
altvalue = value,
singular = (clean == '1'),
clean = clean,
show = clean,
}
unit_table.inout = 'in'
unit_table.valinfo = { info }
local sortspan, scaled_value
if options.sort then
sortspan, scaled_value = make_table_or_sort(parms, value, info, unit_table, options.scaled_top)
end
return {
text = make_id(parms, 1, unit_table),
sortspan = sortspan,
scaled_value = scaled_value,
unknown = not success and true or nil,
}
end

return { convert = main_convert, _unit = _unit }