Complex classes like BaseCollection 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 BaseCollection, and based on these observations, apply Extract Interface, too.
1 | <?php |
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11 | class BaseCollection implements \Iterator, \ArrayAccess, \Countable { |
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12 | |||
13 | /** |
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14 | * @var int |
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15 | */ |
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16 | protected $position = 0; |
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17 | |||
18 | /** |
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19 | * Array of objects |
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20 | * |
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21 | * @var array |
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22 | */ |
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23 | protected $items = []; |
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24 | |||
25 | |||
26 | /** |
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27 | * @var string |
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28 | */ |
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29 | protected $initialContentHash; |
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30 | |||
31 | |||
32 | /** |
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33 | * @param array $items |
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34 | */ |
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35 | public function __construct(array $items = []) { |
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43 | |||
44 | |||
45 | /** |
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46 | * |
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47 | */ |
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48 | public function __clone() { |
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55 | |||
56 | |||
57 | /** |
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58 | * Return number of items in this collection |
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59 | * |
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60 | * @return int |
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61 | */ |
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62 | public function count() { |
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65 | |||
66 | |||
67 | /** |
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68 | * Add one item to begin of collection |
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69 | * This item is accessible via `$collection->getFirst();` |
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70 | * |
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71 | * @param $item |
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72 | * @return $this |
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73 | */ |
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74 | public function prepend(Token $item) { |
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78 | |||
79 | |||
80 | /** |
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81 | * Add one item to the end of collection |
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82 | * This item is accessible via `$collection->getLast();` |
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83 | * |
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84 | * @param $item |
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85 | * @return $this |
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86 | */ |
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87 | public function append(Token $item) { |
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91 | |||
92 | |||
93 | /** |
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94 | * @param int $index |
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95 | * @param array $items |
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96 | * @return $this |
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97 | * @throws \InvalidArgumentException |
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98 | */ |
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99 | public function addAfter($index, $items) { |
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120 | |||
121 | |||
122 | /** |
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123 | * Truncate current list of items and add new |
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124 | * |
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125 | * @param array $items |
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126 | * @return $this |
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127 | */ |
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128 | public function setItems($items) { |
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143 | |||
144 | |||
145 | /** |
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146 | * Remove part of items from collection |
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147 | * Works as array_slice |
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148 | * |
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149 | * |
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150 | * @param $offset |
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151 | * @param null $length |
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152 | * @return $this |
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153 | */ |
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154 | public function slice($offset, $length = null) { |
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158 | |||
159 | |||
160 | /** |
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161 | * Take part of items and return new collection |
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162 | * Works as array_slice |
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163 | * At this point items in 2 collection is same |
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164 | * |
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165 | * @param int $offset |
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166 | * @param null $length |
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167 | * @return self |
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168 | */ |
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169 | public function extractItems($offset, $length = null) { |
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177 | |||
178 | |||
179 | /** |
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180 | * Rewind current collection |
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181 | */ |
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182 | public function rewind() { |
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186 | |||
187 | |||
188 | /** |
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189 | * Return last item from collection |
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190 | * |
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191 | * @return mixed |
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192 | */ |
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193 | public function getLast() { |
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196 | |||
197 | |||
198 | /** |
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199 | * Return first item from collection |
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200 | * @return mixed |
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201 | */ |
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202 | public function getFirst() { |
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205 | |||
206 | |||
207 | /** |
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208 | * Return next item from current |
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209 | * Also can return item with position from current + $step |
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210 | * |
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211 | * @param int $step |
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212 | * @return mixed |
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213 | */ |
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214 | public function getNext($step = 1) { |
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218 | |||
219 | |||
220 | /** |
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221 | * Return previous item |
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222 | * Also can return previous from current position + $step |
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223 | * |
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224 | * @param int $step |
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225 | * @return mixed |
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226 | */ |
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227 | public function getPrevious($step = 1) { |
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231 | |||
232 | |||
233 | /** |
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234 | * Return current item in collection |
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235 | * |
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236 | * @return object |
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237 | */ |
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238 | public function current() { |
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241 | |||
242 | |||
243 | /** |
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244 | * Return current position |
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245 | * |
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246 | * @return int |
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247 | */ |
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248 | public function key() { |
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251 | |||
252 | |||
253 | /** |
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254 | * Switch to next position |
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255 | */ |
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256 | public function next() { |
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259 | |||
260 | |||
261 | /** |
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262 | * Check if item exist in current position |
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263 | * |
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264 | * @return bool |
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265 | */ |
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266 | public function valid() { |
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269 | |||
270 | |||
271 | /** |
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272 | * Add item to the end or modify item with given key |
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273 | * |
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274 | * @param int|null $offset |
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275 | * @param object $item |
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276 | * @return $this |
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277 | */ |
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278 | public function offsetSet($offset, $item) { |
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295 | |||
296 | |||
297 | /** |
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298 | * Check if item with given offset exists |
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299 | * |
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300 | * @param mixed $offset |
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301 | * @return bool |
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302 | */ |
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303 | public function offsetExists($offset) { |
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306 | |||
307 | |||
308 | /** |
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309 | * Remove item from collection |
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310 | * |
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311 | * @param int $offset |
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312 | */ |
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313 | public function offsetUnset($offset) { |
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316 | |||
317 | |||
318 | /** |
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319 | * Get item from collection |
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320 | * |
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321 | * @param int $offset |
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322 | * @return object |
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323 | */ |
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324 | public function offsetGet($offset) { |
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327 | |||
328 | |||
329 | /** |
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330 | * Return array of items connected to this collection |
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331 | * |
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332 | * Rewrite this method in you class |
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333 | * |
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334 | * <code> |
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335 | * foreach($collection->getTokens() as $item){ |
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336 | * echo get_class($item)."\n; |
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337 | * } |
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338 | * </code> |
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339 | * @return Token[] |
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340 | */ |
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341 | public function getTokens() : array { |
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344 | |||
345 | |||
346 | public function getItems() { |
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350 | |||
351 | |||
352 | /** |
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353 | * Iterate over objects in collection |
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354 | * |
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355 | * <code> |
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356 | * $collection->each(function($item, $index, $collection){ |
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357 | * if ( $index > 0 ) { |
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358 | * $item->remove(); |
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359 | * } |
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360 | * }) |
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361 | * </code> |
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362 | * |
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363 | * @param callable $callback |
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364 | * @return $this |
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365 | * @throws \InvalidArgumentException |
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366 | */ |
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367 | public function each(callable $callback) : self { |
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381 | |||
382 | |||
383 | public function map(callable $callback) { |
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387 | |||
388 | |||
389 | /** |
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390 | * Remove all tokens in collection |
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391 | * |
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392 | * @return Collection |
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393 | */ |
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394 | public function remove() { |
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400 | |||
401 | |||
402 | /** |
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403 | * @param int $index |
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404 | */ |
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405 | protected function validateIndex($index) { |
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408 | |||
409 | |||
410 | /** |
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411 | * @return $this |
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412 | */ |
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413 | public function storeContentHash() { |
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417 | |||
418 | |||
419 | /** |
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420 | * @return bool |
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421 | */ |
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422 | public function isChanged() { |
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425 | |||
426 | |||
427 | /** |
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428 | * @return string |
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429 | */ |
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430 | private function getContentHash() { |
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433 | |||
434 | |||
435 | /** |
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436 | * @return string |
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437 | */ |
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438 | public function assemble() { |
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450 | |||
451 | } |
This check looks from parameters that have been defined for a function or method, but which are not used in the method body.