Array library for Lua

array.lua

function string.ordinalize(str)
   local num = tonumber(str)
   local endings = {"st", "nd", "rd"}
   if num >= 11 and num <= 13 then
	  return num .. "th"
   elseif num % 10 > 0 and num % 10 <= #endings then
	  return num .. endings[num % 10]
   else
	  return num .. "th"
   end
end

_array = {
   each =
      function(list, fn, ...)
         local r = array()
         for k,v in pairs(list) do
            r[k] = fn(v, ...)
         end
         return r
      end,

   send =
      function(msg)
         return function(list, ...)
                   local function fn(v, ...)
                      return (v[msg])(v, ...)
                   end

                   return _array.each(list, fn, ...)
                end
      end,

   __index =
      function(t, name)
         if name == 'each' then return _array.each
         else return _array.send(name) end
      end,

   __tostring =
      function(tbl)
         local strings = tbl:each(tostring)
         return '[' .. table.concat(strings, ', ') .. ']'
      end
}

function array(...)
   return setmetatable({...}, _array)
end

A = array

----------

print(A(1,2,3,4):each(function(x) return x*x end))
print(A(1,10,33):each(tostring):ordinalize())
print(A('foo','bar','baz'):sub(1,1))