Module:Yesno

-- Function allowing for consistent treatment of boolean-like wikitext input. -- It works similarly to the template Template:Yesno. return function (val, default)

   val = type(val) == 'string' and mw.ustring.lower(val) or val -- put in lower case
   if val == nil then
       return nil
   elseif val == false or val == 'no' or val == 'n' or val == 'false' or tonumber(val) == 0 then
       return false
   elseif val == true or val == 'yes' or val == 'y' or val == 'true' or tonumber(val) == 1 then
       return true
   elseif default ~= nil then
       return default
   else
       return true
   end

end