function split( str, regex )
  local t = { }
  local fpat = "(.-)"..regex
  local last_end = 1
  local s, e, cap = str:find(fpat, 1)
  while s do
        if s ~= 1 or cap ~= "" then
          table.insert(t,cap)
        end
        last_end = e+1
        s, e, cap = str:find(fpat, last_end)
  end
  if last_end <= #str then
        cap = str:sub(last_end)
        table.insert(t, cap)
  end
  return t
end

local s = "This is a string"
local tableOfParts = split( s, " " )