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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| 10 | class ZanoxEx extends Zanox |
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| 11 | { |
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| 12 | /** |
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| 13 | * Call protected/private method of a class. |
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| 14 | * |
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| 15 | * @param object &$object Instantiated object that we will run method on. |
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| 16 | * @param string $methodName Method name to call |
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| 17 | * @param array $parameters Array of parameters to pass into method. |
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| 18 | * |
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| 19 | * @return mixed Method return. |
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| 20 | */ |
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| 21 | View Code Duplication | public function invokeMethod(&$object,$methodName, array $parameters = array()) |
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| 28 | |||
| 29 | /** |
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| 30 | * Call protected/private property of a class. |
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| 31 | * @param $object |
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| 32 | * @param $propertyName |
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| 33 | * |
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| 34 | * @return mixed |
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| 35 | */ |
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| 36 | View Code Duplication | public function invokeProperty(&$object,$propertyName) |
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| 43 | /** |
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| 44 | * get Sales updated/created on the date passed |
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| 45 | * @param $date |
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| 46 | * @param $page |
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| 47 | * @param $pageSize |
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| 48 | * @param int $iteration |
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| 49 | * |
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| 50 | * @return array |
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| 51 | */ |
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| 52 | private function getSales($date, $page, $pageSize, $iteration = 0) |
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| 67 | } |
Let’s assume that you have a directory layout like this:
. |-- OtherDir | |-- Bar.php | `-- Foo.php `-- SomeDir `-- Foo.phpand let’s assume the following content of
Bar.php:If both files
OtherDir/Foo.phpandSomeDir/Foo.phpare loaded in the same runtime, you will see a PHP error such as the following:PHP Fatal error: Cannot use SomeDir\Foo as Foo because the name is already in use in OtherDir/Foo.phpHowever, as
OtherDir/Foo.phpdoes not necessarily have to be loaded and the error is only triggered if it is loaded beforeOtherDir/Bar.php, this problem might go unnoticed for a while. In order to prevent this error from surfacing, you must import the namespace with a different alias: