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:
Complex classes like DataContainer often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes. You can also have a look at the cohesion graph to spot any un-connected, or weakly-connected components.
Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.
While breaking up the class, it is a good idea to analyze how other classes use DataContainer, and based on these observations, apply Extract Interface, too.
| 1 | <?php |
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| 20 | class DataContainer implements \ArrayAccess, \IteratorAggregate, \Countable |
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| 21 | { |
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| 22 | /** |
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| 23 | * @var DataContainer parent container, for inheritance |
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| 24 | * @since 2.0.0 |
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| 25 | */ |
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| 26 | protected $parent; |
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| 27 | |||
| 28 | /** |
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| 29 | * @var bool wether we want to use parent cascading |
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| 30 | * @since 2.0.0 |
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| 31 | */ |
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| 32 | protected $parentEnabled = false; |
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| 33 | |||
| 34 | /** |
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| 35 | * @var array container data |
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| 36 | * @since 2.0.0 |
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| 37 | */ |
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| 38 | protected $data = array(); |
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| 39 | |||
| 40 | /** |
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| 41 | * @var bool wether the container is read-only |
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| 42 | * @since 2.0.0 |
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| 43 | */ |
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| 44 | protected $readOnly = false; |
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| 45 | |||
| 46 | /** |
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| 47 | * @var bool wether the container data has been modified |
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| 48 | * @since 2.0.0 |
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| 49 | */ |
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| 50 | protected $isModified = false; |
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| 51 | |||
| 52 | /** |
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| 53 | * Constructor |
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| 54 | * |
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| 55 | * @param array $data container data |
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| 56 | * @param boolean $readOnly wether the container is read-only |
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| 57 | * @since 2.0.0 |
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| 58 | */ |
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| 59 | public function __construct(array $data = array(), $readOnly = false) |
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| 64 | |||
| 65 | /** |
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| 66 | * Get the parent of this container |
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| 67 | * |
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| 68 | * @return DataContainer |
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| 69 | * @since 2.0.0 |
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| 70 | */ |
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| 71 | public function getParent() |
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| 75 | |||
| 76 | /** |
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| 77 | * Set the parent of this container, to support inheritance |
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| 78 | * |
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| 79 | * @param DataContainer $parent the parent container object |
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| 80 | * @return $this |
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| 81 | * @since 2.0.0 |
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| 82 | */ |
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| 83 | public function setParent(DataContainer $parent = null) |
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| 98 | |||
| 99 | /** |
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| 100 | * Enable the use of the parent object, if set |
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| 101 | * |
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| 102 | * @return $this |
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| 103 | * @since 2.0.0 |
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| 104 | */ |
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| 105 | public function enableParent() |
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| 114 | |||
| 115 | /** |
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| 116 | * Disable the use of the parent object |
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| 117 | * |
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| 118 | * @return $this |
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| 119 | * @since 2.0.0 |
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| 120 | */ |
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| 121 | public function disableParent() |
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| 127 | |||
| 128 | /** |
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| 129 | * Check whether or not this container has an active parent |
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| 130 | * |
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| 131 | * @return bool |
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| 132 | * @since 2.0.0 |
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| 133 | */ |
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| 134 | public function hasParent() |
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| 138 | |||
| 139 | /** |
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| 140 | * Retrieve the modified state of the container |
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| 141 | * |
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| 142 | * @return bool |
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| 143 | * @since 2.0.0 |
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| 144 | */ |
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| 145 | public function isModified() |
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| 149 | |||
| 150 | /** |
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| 151 | * Replace the container's data. |
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| 152 | * |
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| 153 | * @param array $data new data |
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| 154 | * @return $this |
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| 155 | * @throws RuntimeException |
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| 156 | * @since 2.0.0 |
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| 157 | */ |
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| 158 | public function setContents(array $data) |
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| 171 | |||
| 172 | /** |
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| 173 | * Get the container's data |
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| 174 | * |
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| 175 | * @return array container's data |
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| 176 | * @since 2.0.0 |
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| 177 | */ |
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| 178 | public function getContents() |
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| 189 | |||
| 190 | /** |
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| 191 | * Set wether the container is read-only. |
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| 192 | * |
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| 193 | * @param boolean $readOnly wether it's a read-only container |
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| 194 | * @return $this |
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| 195 | * @since 2.0.0 |
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| 196 | */ |
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| 197 | public function setReadOnly($readOnly = true) |
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| 203 | |||
| 204 | /** |
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| 205 | * Merge arrays into the container. |
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| 206 | * |
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| 207 | * @param array $arg array to merge with |
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| 208 | * @return $this |
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| 209 | * @throws RuntimeException |
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| 210 | * @since 2.0.0 |
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| 211 | */ |
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| 212 | public function merge($arg) |
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| 237 | |||
| 238 | /** |
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| 239 | * Check wether the container is read-only. |
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| 240 | * |
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| 241 | * @return boolean $readOnly wether it's a read-only container |
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| 242 | * @since 2.0.0 |
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| 243 | */ |
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| 244 | public function isReadOnly() |
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| 248 | |||
| 249 | /** |
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| 250 | * isset magic method |
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| 251 | */ |
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| 252 | public function __isset($key) |
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| 256 | |||
| 257 | /** |
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| 258 | * Check if a key was set upon this bag's data |
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| 259 | * |
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| 260 | * @param string $key |
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| 261 | * @return bool |
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| 262 | * @since 2.0.0 |
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| 263 | */ |
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| 264 | public function has($key) |
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| 275 | |||
| 276 | /** |
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| 277 | * get magic method |
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| 278 | */ |
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| 279 | public function __get($key) |
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| 283 | |||
| 284 | /** |
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| 285 | * Get a key's value from this bag's data |
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| 286 | * |
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| 287 | * @param string $key |
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| 288 | * @param mixed $default |
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| 289 | * @return mixed |
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| 290 | * @since 2.0.0 |
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| 291 | */ |
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| 292 | public function get($key = null, $default = null) |
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| 312 | |||
| 313 | /** |
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| 314 | * set magic method |
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| 315 | */ |
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| 316 | public function __set($key, $value) |
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| 320 | |||
| 321 | /** |
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| 322 | * Set a config value |
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| 323 | * |
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| 324 | * @param string $key |
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| 325 | * @param mixed $value |
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| 326 | * @throws \RuntimeException |
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| 327 | * @since 2.0.0 |
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| 328 | */ |
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| 329 | View Code Duplication | public function set($key, $value) |
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| 349 | |||
| 350 | /** |
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| 351 | * Delete data from the container |
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| 352 | * |
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| 353 | * @param string $key key to delete |
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| 354 | * @return boolean delete success boolean |
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| 355 | * @since 2.0.0 |
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| 356 | */ |
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| 357 | View Code Duplication | public function delete($key) |
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| 373 | |||
| 374 | /** |
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| 375 | * Allow usage of isset() on the param bag as an array |
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| 376 | * |
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| 377 | * @param string $key |
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| 378 | * @return bool |
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| 379 | * @since 2.0.0 |
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| 380 | */ |
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| 381 | public function offsetExists($key) |
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| 385 | |||
| 386 | /** |
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| 387 | * Allow fetching values as an array |
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| 388 | * |
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| 389 | * @param string $key |
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| 390 | * @return mixed |
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| 391 | * @throws OutOfBoundsException |
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| 392 | * @since 2.0.0 |
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| 393 | */ |
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| 394 | public function offsetGet($key) |
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| 401 | |||
| 402 | /** |
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| 403 | * Disallow setting values like an array |
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| 404 | * |
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| 405 | * @param string $key |
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| 406 | * @param mixed $value |
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| 407 | * @since 2.0.0 |
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| 408 | */ |
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| 409 | public function offsetSet($key, $value) |
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| 413 | |||
| 414 | /** |
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| 415 | * Disallow unsetting values like an array |
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| 416 | * |
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| 417 | * @param string $key |
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| 418 | * @throws RuntimeException |
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| 419 | * @since 2.0.0 |
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| 420 | */ |
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| 421 | public function offsetUnset($key) |
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| 425 | |||
| 426 | /** |
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| 427 | * IteratorAggregate implementation |
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| 428 | * |
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| 429 | * @return IteratorAggregate iterator |
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| 430 | * @since 2.0.0 |
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| 431 | */ |
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| 432 | public function getIterator() |
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| 436 | |||
| 437 | /** |
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| 438 | * Countable implementation |
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| 439 | * |
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| 440 | * @return int number of items stored in the container |
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| 441 | * @since 2.0.0 |
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| 442 | */ |
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| 443 | public function count() |
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| 447 | } |
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| 448 |
This check looks from parameters that have been defined for a function or method, but which are not used in the method body.