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 | class Form |
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12 | { |
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13 | /** |
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14 | * The form fields. |
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15 | * |
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16 | * @var Collection|Field[] |
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17 | */ |
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18 | protected $fields; |
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19 | |||
20 | /** |
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21 | * The form model. |
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22 | * |
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23 | * @var Model |
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24 | */ |
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25 | protected $model; |
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26 | |||
27 | /** |
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28 | * The form theme. |
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29 | * |
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30 | * @var string |
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31 | */ |
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32 | protected $theme; |
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33 | |||
34 | /** |
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35 | * The helper of former. |
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36 | * |
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37 | * @var FormerHelper |
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38 | */ |
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39 | protected $helper; |
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40 | |||
41 | /** |
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42 | * The action of form. |
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43 | * |
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44 | * @var string |
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45 | */ |
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46 | protected $action; |
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47 | |||
48 | /** |
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49 | * The method of form. |
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50 | * |
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51 | * @var string |
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52 | */ |
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53 | protected $method = 'POST'; |
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54 | |||
55 | /** |
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56 | * Form constructor. |
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57 | * |
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58 | * @param Model|null $model |
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59 | * @param FormerHelper $formerHelper |
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60 | */ |
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61 | public function __construct(Model $model = null, FormerHelper $formerHelper) |
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68 | |||
69 | /** |
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70 | * Get the model fields. |
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71 | * |
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72 | * @return Collection |
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73 | */ |
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74 | public function getFields(): Collection |
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78 | |||
79 | /** |
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80 | * Set the model fields. |
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81 | * |
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82 | * @param string $input |
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83 | * @param string $name |
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84 | * @param array $rules |
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85 | */ |
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86 | public function addField($input, $name, array $rules) |
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96 | |||
97 | /** |
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98 | * Get the form model. |
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99 | * |
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100 | * @return Model |
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101 | */ |
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102 | public function getModel(): Model |
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106 | |||
107 | public function getHelper(): FormerHelper |
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111 | |||
112 | /** |
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113 | * @return string |
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114 | */ |
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115 | public function getAction(): string |
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119 | |||
120 | /** |
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121 | * @return string |
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122 | */ |
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123 | public function getMethod(): string |
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127 | |||
128 | /** |
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129 | * Set the form model. |
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130 | * |
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131 | * @param Model $model |
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132 | */ |
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133 | public function setModel(Model $model) |
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137 | |||
138 | /** |
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139 | * Set the form theme. |
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140 | * |
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141 | * @param string|null $theme |
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142 | */ |
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143 | public function setTheme($theme) |
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147 | |||
148 | public function setAction($action) |
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152 | |||
153 | public function setActionFromRoute($route) |
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157 | |||
158 | public function setMethod($method) |
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162 | |||
163 | public function start() |
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171 | |||
172 | public function end() |
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180 | |||
181 | View Code Duplication | public function field(string $name) |
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192 | |||
193 | View Code Duplication | public function fields() |
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205 | } |
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206 |
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: