private function indentationModeBlock(string $line): int
  {
    $mode = 0;

    if (substr($line, -1, 1)=='{')
    {
      $mode |= self::C_INDENT_INCREMENT_AFTER;

      $this->defaultLevelIncrement();
    }

    if (substr($line, 0, 1)=='}')
    {
      $this->defaultLevelDecrement();

      if ($this->defaultLevelIsZero())
      {
        $mode |= self::C_INDENT_DECREMENT_BEFORE_DOUBLE;

        array_pop($this->defaultLevel);
      }
      else
      {
        $mode |= self::C_INDENT_DECREMENT_BEFORE;
      }
    }

    return $mode;
  }