Duplicate code is one of the most pungent code smells. A rule that is often used is to re-structure code once it is duplicated in three or more places.
Common duplication problems, and corresponding solutions are:
| 1 | <?php  | 
            ||
| 11 | View Code Duplication | class ValueVoter implements VoterInterface  | 
            |
| 12 | { | 
            ||
| 13 | /**  | 
            ||
| 14 |      * {@inheritdoc} | 
            ||
| 15 | */  | 
            ||
| 16 | 5 | public function vote($parameter = null, $user = null, array $additional = [])  | 
            |
| 24 | }  | 
            ||
| 25 |