public function indent($level = null)
    {
        $level = $level ?: $this->getLevel();
        array_push($this->indentStack, $level);

        return $level;
    }
public function indent($level = null)
    {
        $level = $level ?: $this->getLevel();
        array_push($this->indentStack, $level);

        return $level;
    }
public function indent ( $ level = null ) { $ level = $ level ? : $ this -> getLevel ( ) ; array_push ( $ this -> indentStack , $ level ) ; return $ level ; }
Indent and return the new level.

@param null $level

@return int
Indent and return the new level .