code: public function next()
      {
          static $breakCode = array("\r", "\n", "\r\n");
          if (!$this->hasNext()) {
              throw $this->createException("Cannnot read next");
          }
          $result = $this->current;
          if (in_array($result, $breakCode)) {
              $this->row++;
              $this->col = 1;
          } else {
              $this->col++;
          }
          $this->index += ($result === "\r\n") ? 2 : 1;
          $current = $this->computeCurrent();
          $this->current = $current;
          return $current;
      }
docs: index を 1 進めます. 次の文字を返します.
  @return string