Module:Convert
Documentation for this module may be created at Module:Convert/doc
--[[
Later TODO Too many items to list, but following are some points:
- Some conversions require two outputs: {{convert|55|nmi|km mi}}.
- Some units have two values: {{convert|3.21|m|ftin}}.
- Some units use the plural name, not the symbol, example:
{{convert|12|ha}} --should give--> 12 hectares (30 acres)
]]
-- Conversion data is defined in another module because it is too large
-- to be conveniently included here.
-- A testing program can set the global variable 'is_test_run'.
local convertdata = require(is_test_run and "convertdata" or "Module:Convertdata")
local units = convertdata.units
local defaultunits = convertdata.defaultunits
local function strip(text)
-- If text is a string, return its content with no leading/trailing
-- whitespace. Otherwise return nil.
if type(text) == 'string' then
return text:match("^%s*(.-)%s*$")
end
end
-- Configuration options to keep magic values in one location.
local config = {}
local function get_config(frame)
-- Return table of configuration options.
local cfg = {
-- Defaults that can be overridden by template.
numdot = '.', -- decimal mark before fractional digits
numsep = ',', -- thousands separator for numbers (',', '.', or nil)
maxsigfig = 14, -- maximum number of significant figures
}
for k, v in frame:argumentPairs() do
cfg[k] = v -- arguments from template's {{#invoke:}}
end
if cfg.maxsigfig > 20 then
cfg.maxsigfig = 20 -- limit abuse
end
return cfg
end
local function ntsh_complement(text)
-- Return text (string of digits) after subtracting each digit from 9.
local result = ''
local first, last = 1, #text
while first <= last do
local lenblock = last + 1 - first
if lenblock > 12 then
lenblock = 12
end
local block = tonumber(text:sub(first, first + lenblock - 1))
local nines = tonumber(string.rep('9', lenblock))
local fmt = '%0' .. tostring(lenblock) .. '.0f'
result = result .. fmt:format(nines - block)
first = first + lenblock
end
return result
end
local function ntsh(n, debug)
-- Return html text to be used for a hidden sort key so that
-- the given number will be sorted in numeric order.
-- If debug == 'yes', output is in a box (not hidden).
-- This implements Template:Ntsh (number table sorting, hidden).
local result, i, f, style
if n >= 0 then
if n > 1e16 then
result = '~'
else
i, f = math.modf(n)
f = math.floor(1e6 * f)
result = string.format('&1%016.0f%06d', i, f)
end
else
n = -n
if n > 1e16 then
result = '!'
else
i, f = math.modf(n)
f = math.floor(1e6 * f)
result = string.format('%016.0f%06d', i, f)
result = '&0' .. ntsh_complement(result)
end
end
if debug == 'yes' then
style = 'border:1px solid'
else
style = 'display:none'
end
return '<span style="' .. style .. '">' .. result .. '</span>'
end
local function hyphenated(name)
-- Return a hyphenated form of given name (for adjectival usage).
-- 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 US) nautical mile"], and
-- not spaces immediately before '(' or in '(...)' [for cases like
-- "British thermal unit (ISO)" and "Calorie (International Steam Table)"].
local pos
if name:sub(1, 1) == '(' then
pos = name:find(')', 1, true)
if pos ~= nil then
return name:sub(1, pos+1) .. name:sub(pos+2):gsub(' ', '-')
end
elseif name:sub(-1, -1) == ')' then
pos = name:find('(', 1, true)
if pos ~= nil then
return name:sub(1, pos-2):gsub(' ', '-') .. name:sub(pos-1)
end
end
return name:gsub(' ', '-')
end
local function change_sign(text)
-- Change sign of text for correct appearance because it is negated.
if text:sub(1, 1) == '-' then
return text:sub(2)
end
return '-' .. text
end
local function use_minus(text)
-- Return text with Unicode minus instead of '-', if present.
if text:sub(1, 1) == '-' then
return '−' .. text:sub(2)
end
return text
end
local function with_separator(text)
-- Return text with thousand separators inserted.
-- The given text is like '123' or '12345.6789' or '1.23e45'
-- (e notation can only occur when processing an input value).
-- The text has no sign (caller inserts that later, if necessary).
-- Separator is inserted only in the integer part of the significand
-- (not after numdot, and not after 'e' or 'E').
-- Four-digit integer parts have a separator (like '1,234').
local numsep = config.numsep
if numsep == '' then
return text
end
local last = text:match('()[' .. config.numdot .. 'eE]') -- () returns position
if last == nil then
last = #text
else
last = last - 1 -- index of last character before dot/e/E
end
if last >= 4 then
local groups = {}
local first = last % 3
if first > 0 then
table.insert(groups, text:sub(1, first))
end
first = first + 1
while first < last do
table.insert(groups, text:sub(first, first+2))
first = first + 3
end
return table.concat(groups, numsep) .. text:sub(last+1)
end
return text
end
-- Input values can use values like 1.23e12, but are never displayed
-- using exponent notation like 1.23×10¹².
-- Very small or very large output values use exponent notation.
-- Use fmtpower:format(significand, exponent) where each arg is a string.
local fmtpower = '%s<span style="margin-left:0.2em">×<span style="margin-left:0.1em">10</span></span><sup>%s</sup>'
local function with_exponent(show, exponent)
-- Return wikitext to display the implied value in exponent notation.
if #show > 1 then
show = show:sub(1, 1) .. config.numdot .. show:sub(2)
end
return fmtpower:format(show, use_minus(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 <= 0 then
sigfig = 1
elseif sigfig > config.maxsigfig then
sigfig = config.maxsigfig
end
if value == 0 then
return string.rep('0', sigfig), 1
end
local exp, frac = math.modf(math.log10(value))
if frac >= 0 then
frac = frac - 1
exp = exp + 1
end
local digits = tostring(math.floor((10^(frac + sigfig)) + 0.5))
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
local function format_number(show, exponent, isnegative)
-- Return wikitext to display the value implied by the arguments:
-- exponent is nil; and
-- show is a string of digits (no sign), with an optional dot;
-- or:
-- exponent is a number (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').
-- The result:
-- * Includes a Unicode minus if isnegative.
-- * Has numsep inserted where necessary.
-- * Uses exponent notation for very small or large values.
-- * Has no more than config.maxsigfig significant digits
-- (same as old template and {{#expr}}).
local sign
if isnegative then
sign = '−' -- Unicode minus
else
sign = ''
end
local numdot = config.numdot
local maxlen = config.maxsigfig
if exponent == nil then
local integer, dot, fraction = show:match('^(%d*)([' .. numdot .. ']?)(.*)')
if #integer >= 10 then
show = integer .. fraction
exponent = #integer
elseif integer == '0' or integer == '' then
local zeros, figs = fraction:match('^(0*)([^0]?.*)')
if #figs == 0 then
if #zeros > maxlen then
show = '0' .. numdot .. zeros:sub(1, maxlen)
end
elseif #zeros >= 4 then
show = figs
exponent = -#zeros
elseif #figs > maxlen then
show = '0' .. numdot .. zeros .. figs:sub(1, maxlen)
end
else
maxlen = maxlen + #dot
if #show > maxlen then
show = show:sub(1, maxlen)
end
end
end
if exponent ~= nil then
if #show > maxlen then
show = show:sub(1, maxlen)
end
if exponent > 10 or exponent <= -4 or (exponent == 10 and show ~= '1000000000') then
-- Rounded value satisfies: value >= 1e9 or value < 1e-4 (1e9 = 0.1e10).
return sign .. with_exponent(show, exponent-1)
end
if exponent >= #show then
show = show .. string.rep('0', exponent - #show) -- result has no dot
elseif exponent <= 0 then
show = '0' .. numdot .. string.rep('0', -exponent) .. show
else
show = show:sub(1, exponent) .. numdot .. show:sub(exponent+1)
end
end
if isnegative and show:match('^0.?0*$') then
sign = '' -- don't show minus if result is negative but rounds to zero
end
return sign .. with_separator(show)
end
-- Fraction output format (like old template).
-- frac1: sign, numerator, denominator
-- frac2: wholenumber, sign, numerator, denominator
local frac1 = '<span style="white-space:nowrap">%s<sup>%s</sup>⁄<sub>%s</sub></span>'
local frac2 = '<span class="frac nowrap">%s<s style="display:none">%s</s><sup>%s</sup>⁄<sub>%s</sub></span>'
local function extract_fraction(text, negative)
-- If text represents a fraction, return value, show where
-- value is a number and show is a string.
-- Otherwise, return nil.
--
-- In the following, '(3/8)' represents the wikitext required to
-- display a fraction with numerator 3 and denominator 8.
-- In the wikitext, Unicode minus is used for a negative value.
-- text value, show value, show
-- if not negative if negative
-- 3 / 8 0.375, '(3/8)' -0.375, '−(3/8)'
-- 2 + 3 / 8 2.375, '2(3/8)' -1.625, '−2(−3/8)'
-- 2 - 3 / 8 1.625, '2(−3/8)' -2.375, '−2(3/8)'
-- 1 + 20/8 3.5 , '1/(20/8)' 1.5 , '−1/(−20/8)'
-- 1 - 20/8 -1.5., '1(−20/8)' -3.5 , '−1(20/8)'
-- Wherever an integer appears above, numbers like 1.25 or 12.5e-3
-- (which may be negative) are also accepted (like old template).
-- Template interprets '1.23e+2+12/24' as '123(12/24)' = 123.5!
local lhs, negfrac, rhs, numstr, numerator, denstr, denominator, wholestr, whole, value
lhs, denstr = text:match('^%s*([^/]-)%s*/%s*(.-)%s*$')
denominator = tonumber(denstr)
if denominator == nil then return nil end
wholestr, negfrac, rhs = lhs:match('^%s*(.-[^eE])%s*([+-])%s*(.-)%s*$')
if wholestr == nil or wholestr == '' then
wholestr = nil
whole = 0
numstr = lhs
else
whole = tonumber(wholestr)
if whole == nil then return nil end
numstr = rhs
end
negfrac = (negfrac == '-')
numerator = tonumber(numstr)
if numerator == nil then return nil end
if negative == negfrac or wholestr == nil then
value = whole + numerator / denominator
else
value = whole - numerator / denominator
numstr = change_sign(numstr)
end
if tostring(value):find('#', 1, true) then
return nil -- overflow or similar
end
numstr = use_minus(numstr)
denstr = use_minus(denstr)
local wikitext
if wholestr then
local sign = negative and '−' or '+'
if negative then
wholestr = change_sign(wholestr)
end
wikitext = frac2:format(use_minus(wholestr), sign, numstr, denstr)
else
local sign = negative and '−' or ''
wikitext = frac1:format(sign, numstr, denstr)
end
return value, wikitext
end
local missing = { 'Need value', 'Need second value' }
local invalid = { 'Value "%s" must be a number', 'Second value "%s" must be a number' }
local function extract_number(args, index, which)
-- Return true if successfully extract a number from the text in args[index].
-- Otherwise, return false, message.
-- Parameter 'which' (1 or 2) selects which input value is being processed.
-- Before processing, the input text is cleaned:
-- * Any thousand separators (valid or not) are removed.
-- * Any sign (and optional following whitespace) is replaced with
-- '-' (if negative) or '' (otherwise).
-- That replaces Unicode minus with '-'.
-- If successful, following elements in table args are updated
-- (first row applies if which == 1, second otherwise):
-- args.in_value1, args.in_singular1, args.in_clean1, args.in_show1
-- args.in_value2, args.in_singular2, args.in_clean2, args.in_show2
-- Value is a valid number.
-- Singular is true if value is 1 (singular form of units will be used).
-- Singular is false if value is -1 (like old template).
-- Clean is cleaned text with any separators and sign removed.
-- Show is text formatted for output:
-- * Thousand separators are inserted.
-- * If negative, a Unicode minus is used; otherwise the sign
-- is '+' (if the input text used '+'), or is ''.
-- TODO Think about fact that the input value might be like 1.23e+123.
-- Will the exponent break anything?
local text = strip(args[index])
if text == nil or text == '' then return false, missing[which] end
local clean, sign
local numsep = config.numsep
if numsep == '' then
clean = text
else
clean = text:gsub('[' .. numsep .. ']', '') -- use '[.]' if numsep is '.'
end
-- Remove any sign character (assuming a number starts with '.' or a digit).
sign, clean = clean:match('^%s*([^ .%d]*)%s*(.*)')
if sign == nil or clean == nil then
return false, missing[which] -- should never occur
end
local propersign, negative
if sign == '−' or sign == '-' then
propersign = '−' -- Unicode U+2212 MINUS SIGN (UTF-8: e2 88 92)
negative = true
elseif sign == '+' then
propersign = '+'
negative = false
elseif sign == '' then
propersign = ''
negative = false
else
return false, (invalid[which]):format(text)
end
local show, singular
local value = tonumber(clean)
if value == nil then
value, show = extract_fraction(clean, negative)
if value == nil then
return false, (invalid[which]):format(text)
end
singular = false -- any fraction (even with value 1) is regarded as plural
end
if show == nil then
singular = (value == 1)
show = propersign .. with_separator(clean)
end
if negative and (value ~= 0) then
value = -value
end
if which == 1 then
args.in_value1 = value
args.in_singular1 = singular
args.in_clean1 = clean
args.in_show1 = show
else
args.in_value2 = value
args.in_singular2 = singular
args.in_clean2 = clean
args.in_show2 = show
end
return true
end
local function require_integer(text, missing, invalid)
-- Return true, n where n = integer equivalent to given text (or false, message).
-- Input should be the text for a simple integer (no separators, no Unicode minus).
-- Using regex avoids irritations with input like '-0.000001'.
if text == nil then return false, missing end
if string.match(text, '^-?%d+$') == nil then
return false, invalid:format(text)
end
return true, tonumber(text)
end
local function get_parms(pframe)
-- Return true, t where t is a table with all arguments passed to the
-- template converted to named arguments, or return false, message.
-- Except for range, which is nil or a table, the named args that are
-- added here could be provided by the user of the template.
-- 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 range_types = { -- text to separate input, output ranges
['and'] = {' and ', ' and '},
['by'] = {' by ', ' by '},
['to'] = {' to ', ' to '},
['-'] = {'–', '–'},
['to(-)'] = {' to ', '–'},
['x'] = {' by ', ' × '},
['+/-'] = {' ± ', ' ± '},
}
local success, msg
local args = {} -- arguments passed to template
for k, v in pframe:argumentPairs() do
args[k] = v
end
success, msg = extract_number(args, 1, 1)
if not success then return success, msg end
local in_unit, precision
local next = strip(args[2])
local i = 3
local range = range_types[next]
if range == nil then
in_unit = next
else
args.range = range
success, msg = extract_number(args, 3, 2)
if not success then return success, msg end
in_unit = strip(args[4])
i = 5
end
if in_unit == nil then return false, 'Need input unit' end
args.in_unit = in_unit
next = strip(args[i])
i = i + 1
if tonumber(next) == nil then
args.out_unit = next
next = strip(args[i])
if tonumber(next) ~= nil then
i = i + 1
precision = next
end
else
precision = next
end
if args.adj == 'mid' then
args.adj = 'on'
next = args[i]
i = i + 1
if next == nil then
args.mid = ''
else -- mid-text words
if next:sub(1, 1) == '-' then
args.mid = next
else
args.mid = ' ' .. next
end
end
elseif args.adj == 'on' then
args.mid = ''
end
if precision == nil then
if tonumber(args[i]) ~= nil then
precision = strip(args[i])
i = i + 1
end
end
if args.disp == 'x' then
args.joins = { args[i] or '', args[i+1] or '' }
end
args.precision = args.precision or precision -- allow named parameter
return true, args
end
local function default_precision(inclean, invalue, outvalue, parms)
-- Return a default value for precision (an integer like 2, 0, -2).
-- Code follows procedures used in old template.
-- Am putting exceptions to standard calculations here, as they are
-- discovered. Can later decide if something cleaner should be done.
-- LATER: The hand unit of length might need special processing.
local log10 = math.log10
local prec, minprec, adjust
local in_unit_table = parms.in_unit_table
local out_unit_table = parms.out_unit_table
local utype = out_unit_table.utype
local fudge = 1e-14 -- {{Order of magnitude}} adds this, so we do too
-- Find fractional digits, handling cases like inclean = '12.345e6'.
local integer, dot, fraction = inclean:match('^(%d*)([' .. config.numdot .. ']?)(%d*)')
if utype == 'temperature' then
-- LATER: Give an error message if (invalue < in_unit_table.offset): below absolute zero?
adjust = 0
local kelvin = (invalue - in_unit_table.offset) * in_unit_table.scale
if kelvin <= 0 then -- can get zero, or small but negative value due to precision problems
minprec = 2
else
minprec = 2 - math.floor(log10(kelvin) + fudge) -- 3 sigfigs in kelvin
end
else
if invalue == 0 or outvalue <= 0 then
-- We are never called with a negative outvalue, but it might be zero.
-- This is special-cased to avoid calculation exceptions.
return 0
end
if out_unit_table.symbol == 'ft' and dot == '' then
-- More precision when output ft with integer input value.
adjust = -log10(in_unit_table.scale)
else
adjust = log10(math.abs(invalue / outvalue))
end
adjust = adjust + log10(2)
-- Ensure that the output has at least two significant figures.
minprec = 1 - math.floor(log10(outvalue) + fudge)
end
if dot == '' then
prec = -integer:match('0*$'):len() -- '12300' gives -2, but so does '12300e-5'
else
if fraction == '' and utype ~= 'temperature' then
prec = 1 -- "123." has same precision as "123.0", like old template
else
prec = #fraction
end
end
return math.max(math.floor(prec + adjust), minprec)
end
local function convert(value, in_unit, out_unit)
local inscale = in_unit.scale
local outscale = out_unit.scale
if in_unit.invert ~= nil then
if in_unit.invert * out_unit.invert < 0 then
return 1 / (value * inscale * outscale)
end
return value * (inscale / outscale)
elseif in_unit.offset ~= nil then
return (value - in_unit.offset) * (inscale / outscale) + out_unit.offset
else
return value * (inscale / outscale)
end
end
local function cvtround(invalue, inclean, parms)
-- Return true, show, singular
-- where
-- show = '' if invalue is nil or ''. Otherwise:
-- show = rounded, formatted string from converting invalue,
-- using the rounding specified in parms.
-- singular = true if result is positive, and (after rounding)
-- is "1", or like "1.00".
-- or return false, message if problem.
-- This code combines convert/round because some rounding requires
-- knowledge of what we are converting.
-- TODO Limit values to avoid abuse (for example, can currently set
-- precision to very large values like 999).
local show, exponent, singular = '', nil, false
if invalue == nil or invalue == '' then
return true, show, singular
end
local outvalue = convert(invalue, parms.in_unit_table, parms.out_unit_table)
local isnegative
if outvalue < 0 then
isnegative = true
outvalue = -outvalue
end
local success
local precision = parms.precision
local sigfig = parms.sigfig
local disp = parms.disp
if precision then
-- Ignore sigfig, disp.
success, precision = require_integer(precision, 'Need value', 'precision "%s" must be an integer')
if not success then return false, precision end
elseif sigfig then
-- Ignore disp.
success, sigfig = require_integer(sigfig, 'Need value', 'sigfig "%s" must be an integer')
if not success then return false, sigfig end
if sigfig <= 0 then
local msg = 'sigfig "%s" must be positive'
return false, msg:format(parms.sigfig)
end
show, exponent = make_sigfig(outvalue, sigfig)
elseif disp == '5' then
outvalue = math.floor((outvalue / 5) + 0.5) * 5
show = string.format('%.0f', outvalue)
else
precision = default_precision(inclean, invalue, outvalue, parms)
end
if precision then
if precision >= 0 then
if precision <= 8 then
-- Add a fudge to handle common cases of bad rounding due to inability
-- to precisely represent some values. This makes the following work:
-- {{convert|-100.1|C|K}} and {{convert|5555000|um|m|2}}.
-- Old template uses #expr round, which invokes PHP round().
-- LATER: Investigate how PHP round() works.
outvalue = outvalue + 2e-14
end
local fmt = '%.' .. string.format('%d', precision) .. 'f'
show = string.format(fmt, outvalue)
else
precision = -precision -- #digits to zero (in addition to digits after dot)
local shift = 10 ^ precision
if shift > outvalue then
show = '0' -- like old template, user can zero all digits
else
show = tostring(math.floor(outvalue/shift + 0.5))
exponent = #show + precision
end
end
end
if (show == '1' or show:match('^1%.0*$') ~= nil) and not isnegative then
-- Use match because on some systems 0.99999999999999999 is 1.0.
singular = true
end
return true, format_number(show, exponent, isnegative), singular
end
local function linked(in_id, out_id, parms)
-- Return in_id, out_id after modifying none, one, or both by replacing
-- the text with a wikilink, if requested in template.
local function substitute(link)
-- TODO Work out how to insert a reasonable prefix in %s.
return link:gsub('%%s', 'xxx', 1)
end
local lk = parms.lk
if lk == 'in' or lk == 'on' then
local link = parms.in_unit_table.link
if link ~= nil then
link = substitute(link)
in_id = '[[' .. link .. '|' .. in_id .. ']]'
end
end
if lk == 'out' or lk == 'on' then
local link = parms.out_unit_table.link
if link ~= nil then
link = substitute(link)
out_id = '[[' .. link .. '|' .. out_id .. ']]'
end
end
return in_id, out_id
end
-- TODO Think about when to use ' ' and when to use ' '.
-- Old template always uses nbsp before a unit symbol, but seems inconsistent
-- before a unit name. Something suggested value 1000 was a threshold
-- (use nbsp for smaller values), but no conclusive results.
-- Possibly a concern is wrapping when using {{convert}} in a table
-- (don't want to force a column to be unnecessarily wide by using nbsp).
local disp_joins = {
['or'] = { ' or ', '' },
['sqbr'] = { ' [' , ']' },
['comma'] = { ', ' , '' },
['slash'] = { ' / ' , '' },
['s'] = { ' / ' , '' },
['b'] = { ' (' , ')' },
}
local function evaluate_condition(value, condition)
-- Return true or false from applying a conditional expression to value,
-- or throw an error if invalid.
-- A very limited set of expressions is supported:
-- v < 9
-- v * 9 < 9
-- where
-- 'v' is replaced with value
-- 9 is any number (as defined by Lua tonumber)
-- '<' can also be '<=' or '>' 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('^%s*v%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
elseif 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, message.
-- 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 pipe-delimited field is an
-- expression that uses 'v' to represent the input value.
-- Example: 'v < 120 | small | big | suffix' (suffix is optional)
-- evaluates 'v < 120' as a boolean with result
-- 'smallsuffix' if (value < 120), or 'bigsuffix' otherwise.
local success, default = defaultunits:lookup(unit_table)
if success then
if default:find('|', 1, true) == nil then
return true, default
end
local t = {}
default = default .. '|' -- to get last item
for item in default:gmatch('%s*(.-)%s*|') do
table.insert(t, item) -- split on '|', removing leading/trailing whitespace
end
if #t == 3 or #t == 4 then
local success, result = pcall(evaluate_condition, value, t[1])
if success then
default = result and t[2] or t[3]
if #t == 4 then
default = default .. t[4]
end
return true, default
end
end
local msg = 'Unit "%s" has an invalid default.[[Category:Convert unknown unit]]'
default = msg:format(unit_table.prefix .. unit_table.baseunit)
end
return false, default
end
local function process(parms)
-- Return true, s where s = final wikitext result (or false, message).
-- TODO Clean up: avoid repeatedly accessing the same field in parms,
-- and avoid the clumsy calculation of items that are not needed.
local success, t
success, t = units:lookup(parms.in_unit, parms.sp)
if success then parms.in_unit_table = t else return success, t end
if parms.out_unit == nil then -- need to catch empty string also?
success, t = get_default(parms.in_value1, parms.in_unit_table)
if success then parms.out_unit = t else return success, t end
end
success, t = units:lookup(parms.out_unit, parms.sp, true)
if success then parms.out_unit_table = t else return success, t end
local in_utype = parms.in_unit_table.utype
if in_utype ~= parms.out_unit_table.utype then
local msg = 'Cannot convert "%s" to "%s".[[Category:Convert dimension mismatch]]'
return false, msg:format(in_utype, parms.out_unit_table.utype)
end
if parms.out_unit_table.combination then
local msg = 'Combinations not implemented, "%s"'
return false, msg:format(parms.out_unit)
end
local outshow1, outshow2, outsingular1, outsingular2
success, outshow1, outsingular1 = cvtround(parms.in_value1, parms.in_clean1, parms)
if not success then return success, outshow1 end
success, outshow2, outsingular2 = cvtround(parms.in_value2, parms.in_clean2, parms)
if not success then return success, outshow2 end
local inshow1, inshow2 = parms.in_show1, parms.in_show2
local inkey, outkey = 'name2', 'name2'
local insymkey, outsymkey = 'symbol', 'symbol'
if parms.adj == 'on' then -- TODO how process second input value?
inkey = 'name1'
elseif parms.in_singular1 then -- TODO how process second input value?
inkey = 'name1'
end
if outsingular1 then
outkey = 'name1'
end
if parms.sp == 'us' or parms.in_unit_table.sp_us then
inkey = inkey .. '_us'
insymkey = 'sym_us'
end
if parms.sp == 'us' or parms.out_unit_table.sp_us then
outkey = outkey .. '_us'
outsymkey = 'sym_us'
end
if parms.in_unit_table.usename then
insymkey = inkey
end
if parms.out_unit_table.usename then
outsymkey = outkey
end
local in_name = parms.in_unit_table[inkey] -- will not need to calculate all of these
local in_symbol = parms.in_unit_table[insymkey]
local out_name = parms.out_unit_table[outkey]
local out_symbol = parms.out_unit_table[outsymkey]
local abbr = parms.abbr
local in_id, out_id = in_symbol, out_symbol
local istemperature = (in_utype == 'temperature')
if abbr == 'on' then -- all symbols
-- Both symbols.
elseif abbr == 'off' then -- all names
in_id = in_name
out_id = out_name
elseif abbr == 'in' then -- input symbols
-- Both symbols.
elseif abbr == 'out' then -- output symbols [is this just the default?]
if not istemperature then
in_id = in_name
end
elseif abbr == 'values' then -- show only values
-- TODO Probably more needed (no preceding space for a start).
in_id = ''
out_id = ''
elseif abbr == 'mos' then -- for ranges, abbreviate with input unit repeated
-- LATER
else -- default
if not istemperature then
in_id = in_name
end
end
in_id, out_id = linked(in_id, out_id, parms)
---BEGIN TO-DO------------Put following in cvtround---------------------
local range = parms.range
local in_block, in_extra, out_block
if parms.adj == 'on' then
in_extra = '-' .. hyphenated(in_id) .. parms.mid
else
in_extra = ' ' .. in_id
end
if range == nil then
in_block = inshow1
out_block = outshow1
else
in_block = inshow1 .. range[1] .. inshow2
out_block = outshow1 .. range[2] .. outshow2
end
local disp = parms.disp
if disp == 'output only' then
in_block = ''
out_block = out_block .. ' ' .. out_id
parms.joins = { '', '' }
elseif disp == 'output number only' or disp == 'number' then
in_block = ''
out_block = out_block
parms.joins = { '', '' }
elseif disp == 'unit' then
if parms.adj == 'on' then
in_block = hyphenated(in_id)
else
in_block = in_id
end
out_block = ''
parms.joins = { '', '' }
elseif disp == 'unit2' then -- is 'unit2' in old template?
in_block = ''
out_block = out_id
parms.joins = { '', '' }
elseif disp == 'flip' then
in_block = out_block .. ' ' .. out_id
out_block = in_block .. in_extra
parms.joins = disp_joins['b']
elseif disp == 'x' then
in_block = in_block .. in_extra
out_block = out_block .. ' ' .. out_id
else
in_block = in_block .. in_extra
out_block = out_block .. ' ' .. out_id
parms.joins = disp_joins[disp] or disp_joins['b']
end
parms.in_block = in_block
parms.out_block = out_block
---END TO-DO------------------------------------------------------------
local wikitext = parms.in_block .. parms.joins[1] .. parms.out_block .. parms.joins[2]
if parms.sortable == 'on' then
wikitext = ntsh(parms.in_value1, parms.debug) .. wikitext
end
return true, wikitext
end
local p = {}
-- A testing program can set the global variable 'is_test_run'.
-- The following sets global variable 'mw' to simulate what Scribunto will do.
local bodge = require(is_test_run and "mw" or "Module:mw") -- fix up mw.text.tag
function p.convert(frame)
config = get_config(frame)
local pframe = frame:getParent()
local success, parms, text
success, parms = get_parms(pframe)
if success then
success, text = process(parms)
else
text = parms
end
if not success then
local params = {style="color:black; background-color:orange;"}
text = mw.text.tag({name="span", contents="[[Module talk:Convert|Conversion error]]: " .. text, params=params})
end
return text
end
return p