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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| 25 | class CommentsPreload extends PreloadItem |
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| 26 | { |
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| 27 | /** |
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| 28 | * listen for core.include.common.classmaps |
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| 29 | * add any module specific class map entries |
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| 30 | * |
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| 31 | * @param mixed $args not used |
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| 32 | * |
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| 33 | * @return void |
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| 34 | */ |
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| 35 | public static function eventCoreIncludeCommonClassmaps($args) |
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| 43 | |||
| 44 | public static function eventCoreFooterStart($args) |
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| 49 | |||
| 50 | View Code Duplication | public static function eventSystemModuleUpdateConfigs(ConfigCollector $collector) |
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| 62 | |||
| 63 | View Code Duplication | public static function eventSystemModuleInstall(XoopsModule $module) |
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| 70 | |||
| 71 | /** |
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| 72 | * remove any comeents for module being uninstalled |
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| 73 | * |
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| 74 | * @param XoopsModule $module module object |
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| 75 | * |
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| 76 | * @return void |
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| 77 | */ |
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| 78 | View Code Duplication | public static function eventSystemModuleUninstall(XoopsModule $module) |
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| 85 | |||
| 86 | View Code Duplication | public static function eventSystemPreferencesForm(XoopsModule $module) |
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| 94 | } |
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| 95 |
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: