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  | 
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| 18 | View Code Duplication | class Context implements ContextInterface  | 
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| 19 | { | 
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| 20 | |||
| 21 | /**  | 
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| 22 | * @var string $slug  | 
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| 23 | */  | 
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| 24 | private $slug;  | 
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| 25 | |||
| 26 | /**  | 
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| 27 | * @var string $description  | 
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| 28 | */  | 
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| 29 | private $description;  | 
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| 30 | |||
| 31 | |||
| 32 | /**  | 
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| 33 | * Context constructor.  | 
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| 34 | *  | 
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| 35 | * @param string $slug  | 
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| 36 | * @param string $description  | 
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| 37 | */  | 
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| 38 | public function __construct($slug, $description)  | 
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| 43 | |||
| 44 | |||
| 45 | /**  | 
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| 46 | * @return string  | 
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| 47 | */  | 
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| 48 | public function slug()  | 
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| 52 | |||
| 53 | |||
| 54 | /**  | 
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| 55 | * @param string $slug  | 
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| 56 | */  | 
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| 57 | private function setSlug($slug)  | 
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| 61 | |||
| 62 | |||
| 63 | /**  | 
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| 64 | * @return string  | 
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| 65 | */  | 
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| 66 | public function description()  | 
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| 70 | |||
| 71 | |||
| 72 | /**  | 
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| 73 | * @param string $description  | 
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| 74 | */  | 
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| 75 | private function setDescription($description)  | 
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| 79 | |||
| 80 | }  | 
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| 81 | // Location: Context.php  | 
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| 82 |