text: CREATE LUA SCALAR SCRIPT map_words(w varchar(10000))
  EMITS (words varchar(100)) AS
  function run(ctx)
      local word = ctx.w
      if (word ~= null)
      then
          for i in unicode.utf8.gmatch(word,'([%w%p]+)')
          do
              ctx.emit(i)
          end
      end
  end
  /
  