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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| 20 | View Code Duplication | class xsGYear extends xsAnySimpleType  | 
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| 21 | { | 
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| 22 | use MinMaxTrait;  | 
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| 23 | |||
| 24 | /**  | 
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| 25 | * Construct.  | 
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| 26 | *  | 
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| 27 | * @param string $value  | 
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| 28 | */  | 
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| 29 | public function __construct($value)  | 
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| 30 |     { | 
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| 31 | parent::__construct($value);  | 
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| 32 |         $this->setWhiteSpaceFacet('collapse'); | 
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| 33 | }  | 
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| 34 | |||
| 35 | public function fixValue()  | 
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| 36 |     { | 
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| 37 | parent::fixValue();  | 
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| 38 | $yearObject = CalenderFactory::fromYear($this->value);  | 
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| 39 | }  | 
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| 40 | |||
| 41 | protected function isOK()  | 
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| 45 | }  | 
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| 46 | 
This check looks for variable assignements that are either overwritten by other assignments or where the variable is not used subsequently.
Both the
$myVarassignment in line 1 and the$higherassignment in line 2 are dead. The first because$myVaris never used and the second because$higheris always overwritten for every possible time line.