Module:ConvertIB
From Roses, Tulips, & Liberty
Documentation for this module may be created at Module:ConvertIB/doc
require('strict')
local p = {}
local getArgs = require('Module:Arguments').getArgs
-- Units accepted by {{convert}} that come in groups (e.g., "5 ft 6 in")
local multiple =
{'mich', 'michlk', 'michainlk', 'miyd', 'miydftin', 'mift', 'ydftin', 'ydft',
'ftin', 'footin', 'handin', 'lboz', 'stlb', 'stlboz', 'stlb'}
-- Convert unit list to hash
local mult_table = {}
for _, v in ipairs(multiple) do
mult_table[v] = true
end
-- Function to pull out values and units from numeric args
-- Returns:
-- values: list of numeric values, or "false" if no numeric argument is given
-- units: list of units (str)
-- value: if there is a last numeric value unpaired with a unit, it becomes the precision
-- anyValue: whether there is a non-false value in the values list
local function parseValuesUnits(args)
local values = {}
local units = {}
local indx = 1
local value = nil
local anyValue = false
-- loop through numeric arguments in pairs
while args[indx] or args[indx+1] do
value = args[indx]
anyValue = anyValue or value
-- if there is a unit, save in output lists
if args[indx+1] then
table.insert(values, value or false)
table.insert(units, args[indx+1])
value = nil
end
indx = indx+2
end
return values, units, value, anyValue
end
-- Function to identify multiple units and rewrite them as new input or output groups
-- Args:
-- values, units: numeric values and units, as lists with same length
-- Returns:
-- newValues, newUnits: same lists rewritten
local function parseMultiples(values, units)
local newValues = {}
local newUnits = {}
local i = 1
-- we will search for multiples with up to 4 entries (depending on length)
local maxMultiple = math.min(4,#units-1)
local valueFound = false -- flag to suppress second (and later) input values
--- Hack for handling "stone": check if only value supplied is "lb"
local onlyPounds = true
for i = 1, #units do
if values[i] and units[i] ~= 'lb' then
onlyPounds = false
break
end
end
-- sweep through units
while i <= #units do
-- determine index of last possible unit that could contain a multiple
local last_unit = math.min(i+maxMultiple-1,#units)
local multipleFound = false
-- try from longest multiple down to double multiple (prefer longest ones)
for j = last_unit, i+1, -1 do
local key = table.concat({unpack(units,i,j)}, '')
if mult_table[key] then
-- we found a multiple unit
multipleFound = true
-- Hack for "stone": add either 'lb' or multiple unit string to output units
-- depending on whether 'lb' was the only unit string with a value
if mw.ustring.sub(key,1,2) == 'st' then
table.insert(newValues, false)
table.insert(newUnits, onlyPounds and key or 'lb')
end
-- if there are any value in the span of the multiple,
-- then the multiple is an input
-- assume all missing values after the first are zero
local firstValueFound = false
for k = i, j do
firstValueFound = not valueFound and (firstValueFound or values[k])
if firstValueFound then
table.insert(newValues, values[k] or 0)
table.insert(newUnits, units[k])
end
end
valueFound = valueFound or firstValueFound
-- if no values in the span of the multiple,
-- then the multiple is an output. Insert combined string as output unit
if not firstValueFound then
table.insert(newValues, false)
table.insert(newUnits, key)
end
i = j+1
break
end
end
--- If no multiple unit was found, insert value[i] and unit[i] into rewritten lists
if not multipleFound then
if valueFound then
table.insert(newValues, false) -- skip writing value if it is a duplicate
else
table.insert(newValues,values[i])
valueFound = values[i]
end
table.insert(newUnits, units[i])
i = i+1
end
end
return newValues, newUnits
end
-- Implement {{convinfobox}}
function p._convert(args)
-- find all values and units in numeric args (and the precision, if it exists)
local values, units, precision, anyValue = parseValuesUnits(args)
-- bail if no values at all
if not anyValue then
return nil
end
-- rewrite values and units if multiple units are found
values, units = parseMultiples(values, units)
-- sort input and outputs into different buckets
local input_values = {}
local input_units = {}
local output_units = {}
for i = 1, #units do
if values[i] then
table.insert(input_values, values[i])
table.insert(input_units, units[i])
else
table.insert(output_units, units[i])
end
end
-- bail if nothing to convert
if #input_values == 0 or #output_units == 0 then
return nil
end
-- assemble argument list to {{convert}}
local innerArgs = {}
-- First, pass all input unit(s)
for i, v in ipairs(input_values) do
table.insert(innerArgs,v)
table.insert(innerArgs,input_units[i])
end
-- Then the output unit(s) [concatenated as single argument]
table.insert(innerArgs,table.concat(output_units,"+"))
if precision then
table.insert(innerArgs,precision) -- last non-nil value contains precision
end
-- now handle all non-numeric arguments, passing to {{convert}}
innerArgs.abbr = 'on' -- abbr=on by default
for k, v in pairs(args) do
if not tonumber(k) then
innerArgs[k] = v
end
end
-- Call {{convert}} with innerArgs
local frame = mw.getCurrentFrame()
return frame:expandTemplate{title='Convert', args=innerArgs}
end
function p.convert(frame)
local args = getArgs(frame)
return p._convert(args) or ""
end
return p