Module:Ancient Egypt era

local data = mw.loadData( 'Module:Ancient Egypt era/data' )
local lang = mw.language.getContentLanguage()

local p = {}

function p._main( inputYear )
 -- Convert the input to an integer if possible. Return "N/A" if the input could
 -- not be converted, or if the converted input is too big or too small.
 inputYear = tonumber( inputYear )
 if not inputYear or inputYear > tonumber( lang:formatDate( 'Y' ) ) then
  return "''N/A''"
 end

 -- Find the length of the data.
 -- We need the length of the data so that we can loop through it backwards.
 -- Normally we can get the length of tables with the # operator, but this
 -- doesn't work with mw.loadData, as mw.loadData uses a metatable, and the
 -- # operator doesn't work for tables that use metatables.
 local dataLength = 0
 for i, t in ipairs( data ) do
  dataLength = i
 end

 -- Find the year in the data page and display the output.
 for i = dataLength, 1, -1 do
  local t = data[i]
  if inputYear - 1 >= t.dynstart and inputYear - 1 <= t.dynend then
   -- year of the dynasty, test with = p._main( -495 )
   -- The input year in the calendar is one after the expected (-775 for the year 776 BC). This is why all values need to be corrected by 1. 
   return string.format(
    '[[%s|%s]] [[List of ancient Egyptian dynasties|dynasty]], %d',
    t.dynlink, t.dynasty, inputYear - t.dynstart
   )
  end
 end
end

function p.main( frame )
 -- If you only want to run this module from another Lua module, you can get
 -- rid of this function entirely. This function is only used if you want to
 -- run this individual module from a template.
 local args = require( 'Module:Arguments' ).getArgs( frame, {
  parentOnly = true
 } )
 return p._main( args[ 1 ] )
end

return p