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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11 | View Code Duplication | class View2 |
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12 | { |
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13 | /** |
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14 | * @var $template Template file or array |
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15 | * @var $templateData Data to send to template file |
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16 | * @var $sortOrder For sorting views |
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17 | * @var $type Type of view |
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18 | */ |
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19 | private $template; |
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20 | private $templateData = []; |
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21 | private $sortOrder; |
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22 | private $type; |
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23 | |||
24 | |||
25 | |||
26 | /** |
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27 | * Set values for the view. |
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28 | * |
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29 | * @param array|string $template the template file, or array |
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30 | * @param array $data variables to make available to the |
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31 | * view, default is empty |
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32 | * @param integer $sort which order to display the views, |
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33 | * if suitable |
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34 | * @param string $type which type of view |
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35 | * |
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36 | * @return self |
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37 | */ |
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38 | public function set($template, $data = [], $sort = 0, $type = "file") |
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70 | |||
71 | |||
72 | |||
73 | /** |
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74 | * Render the view. |
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75 | * |
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76 | * @param object $di optional with access to the framework resources. |
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77 | * |
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78 | * @return void |
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79 | */ |
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80 | public function render($di = null) |
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110 | |||
111 | |||
112 | |||
113 | /** |
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114 | * Give the sort order for this view. |
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115 | * |
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116 | * @return int |
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117 | */ |
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118 | public function sortOrder() |
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122 | } |
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123 |
Let’s assume that you have a directory layout like this:
and let’s assume the following content of
Bar.php
:If both files
OtherDir/Foo.php
andSomeDir/Foo.php
are 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.php
However, as
OtherDir/Foo.php
does 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: