Complex classes like AbstractCollection 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 AbstractCollection, and based on these observations, apply Extract Interface, too.
1 | <?php |
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45 | abstract class AbstractCollection implements |
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46 | ArrayAccess, |
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47 | Countable, |
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48 | Iterator |
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49 | /*Collectable*/ |
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50 | { |
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51 | /** |
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52 | * @var array The collection of data this object represents |
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53 | */ |
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54 | protected $data = []; |
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55 | |||
56 | /** |
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57 | * @var boolean True unless we have advanced past the end of the data array |
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58 | */ |
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59 | protected $isValid = true; |
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60 | |||
61 | /** |
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62 | * AbstractCollection constructor. |
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63 | * |
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64 | * @param mixed $data The data to wrap |
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65 | */ |
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66 | public function __construct($data = []) |
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70 | |||
71 | /** |
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72 | * Invoke object. |
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73 | * |
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74 | * Magic "invoke" method. Called when object is invoked as if it were a function. |
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75 | * |
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76 | * @param mixed $val The value (depends on other param value) |
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77 | * @param mixed $index The index (depends on other param value) |
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78 | * @return mixed (Depends on parameter values) |
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79 | */ |
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80 | public function __invoke($val = null, $index = null) |
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97 | |||
98 | /** BEGIN ArrayAccess methods */ |
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99 | |||
100 | /** |
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101 | * Whether a offset exists. |
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102 | * |
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103 | * @param mixed $offset An offset to check for. |
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104 | * @return boolean true on success or false on failure. |
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105 | * @link http://php.net/manual/en/arrayaccess.offsetexists.php |
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106 | */ |
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107 | public function offsetExists($offset) |
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111 | |||
112 | /** |
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113 | * Offset to retrieve. |
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114 | * |
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115 | * @param mixed $offset The offset to retrieve. |
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116 | * @return mixed Can return all value types. |
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117 | * @link http://php.net/manual/en/arrayaccess.offsetget.php |
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118 | */ |
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119 | public function offsetGet($offset) |
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123 | |||
124 | /** |
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125 | * Offset to set. |
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126 | * |
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127 | * @param mixed $offset The offset to assign the value to. |
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128 | * @param mixed $value The value to set. |
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129 | * @link http://php.net/manual/en/arrayaccess.offsetset.php |
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130 | */ |
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131 | public function offsetSet($offset, $value) |
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135 | |||
136 | /** |
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137 | * Offset to unset. |
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138 | * |
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139 | * @param mixed $offset The offset to unset. |
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140 | * @link http://php.net/manual/en/arrayaccess.offsetunset.php |
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141 | */ |
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142 | public function offsetUnset($offset) |
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146 | |||
147 | /** END ArrayAccess methods */ |
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148 | |||
149 | /** BEGIN Countable methods */ |
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150 | |||
151 | public function count() |
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155 | |||
156 | /** END Countable methods */ |
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157 | |||
158 | /** BEGIN Iterator methods */ |
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159 | |||
160 | /** |
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161 | * Return the current element. |
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162 | * |
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163 | * Returns the current element in the collection. The internal array pointer |
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164 | * of the data array wrapped by the collection should not be advanced by this |
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165 | * method. No side effects. Return current element only. |
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166 | * |
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167 | * @return mixed |
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168 | */ |
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169 | public function current () |
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173 | |||
174 | /** |
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175 | * Return the current key. |
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176 | * |
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177 | * Returns the current key in the collection. No side effects. |
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178 | * |
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179 | * @return mixed |
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180 | */ |
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181 | public function key () |
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185 | |||
186 | /** |
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187 | * Advance the internal pointer forward. |
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188 | * |
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189 | * Although this method will return the current value after advancing the |
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190 | * pointer, you should not expect it to. The interface does not require it |
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191 | * to return any value at all. |
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192 | * |
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193 | * @return mixed |
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194 | */ |
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195 | public function next () |
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204 | |||
205 | /** |
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206 | * Rewind the internal pointer. |
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207 | * |
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208 | * Return the internal pointer to the first element in the collection. Again, |
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209 | * this method is not required to return anything by its interface, so you |
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210 | * should not count on a return value. |
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211 | * |
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212 | * @return mixed |
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213 | */ |
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214 | public function rewind () |
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219 | |||
220 | /** |
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221 | * Is internal pointer in a valid position? |
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222 | * |
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223 | * If the internal pointer is advanced beyond the end of the collection, this method will return false. |
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224 | * |
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225 | * @return bool True if internal pointer isn't past the end |
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226 | */ |
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227 | public function valid () |
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231 | |||
232 | /** END Iterator methods */ |
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233 | |||
234 | /** |
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235 | * Set collection data. |
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236 | * |
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237 | * Sets the collection data. |
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238 | * |
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239 | * @param array $data The data to wrap |
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240 | * @return $this |
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241 | */ |
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242 | protected function setData($data) |
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256 | |||
257 | public function sort($alg = null) |
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265 | |||
266 | /** |
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267 | * Does this collection have a value at given index? |
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268 | * |
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269 | * @param mixed $index The index to check |
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270 | * @return bool |
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271 | */ |
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272 | public function has($index) |
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276 | |||
277 | /** |
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278 | * Get value at a given index. |
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279 | * |
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280 | * Accessor for this collection of data. You can optionally provide a default |
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281 | * value for when the collection doesn't find a value at the given index. It can |
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282 | * also optionally throw an OutOfBoundsException if no value is found. |
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283 | * |
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284 | * @param mixed $index The index of the data you want to get |
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285 | * @param mixed $default The default value to return if none available |
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286 | * @param bool $throw True if you want an exception to be thrown if no data found at $index |
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287 | * @throws OutOfBoundsException If $throw is true and $index isn't found |
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288 | * @return mixed The data found at $index or failing that, the $default |
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289 | * @todo Use OffsetGet, OffsetSet, etc. internally here and on set, has, delete, etc. |
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290 | */ |
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291 | public function get($index, $default = null, $throw = false) |
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301 | |||
302 | /** |
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303 | * Set a value at a given index. |
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304 | * |
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305 | * Setter for this collection. Allows setting a value at a given index. |
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306 | * |
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307 | * @param mixed $index The index to set a value at |
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308 | * @param mixed $val The value to set $index to |
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309 | * |
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310 | * @return $this |
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311 | */ |
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312 | public function set($index, $val) |
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318 | |||
319 | /** |
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320 | * Unset a value at a given index. |
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321 | * |
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322 | * Unset (delete) value at the given index. |
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323 | * |
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324 | * @param mixed $index The index to unset |
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325 | * @param bool $throw True if you want an exception to be thrown if no data found at $index |
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326 | * |
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327 | * @throws OutOfBoundsException If $throw is true and $index isn't found |
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328 | * |
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329 | * @return $this |
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330 | */ |
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331 | public function delete($index, $throw = false) |
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343 | |||
344 | /** |
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345 | * Does this collection have a value at specified numerical position? |
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346 | * |
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347 | * Returns true if collection contains a value (any value including null) |
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348 | * at specified numerical position. |
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349 | * |
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350 | * @param int $pos The position |
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351 | * |
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352 | * @return bool |
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353 | * |
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354 | * @todo I feel like it would make more sense to have this start at position 1 rather than 0 |
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355 | */ |
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356 | public function hasPosition($pos) |
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365 | |||
366 | /** |
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367 | * Return value at specified numerical position. |
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368 | * |
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369 | * @param int $pos The numerical position |
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370 | * |
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371 | * @throws OutOfBoundsException if no pair at position |
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372 | * |
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373 | * @return mixed |
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374 | */ |
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375 | public function getValueAtPosition($pos) |
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379 | |||
380 | /** |
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381 | * Return key at specified numerical position. |
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382 | * |
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383 | * @param int $pos The numerical position |
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384 | * |
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385 | * @throws OutOfBoundsException if no pair at position |
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386 | * |
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387 | * @return mixed |
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388 | */ |
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389 | public function getKeyAtPosition($pos) |
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400 | |||
401 | /** |
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402 | * @param int $pos The numerical position |
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403 | * |
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404 | * @throws OutOfBoundsException if no pair at position |
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405 | * |
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406 | * @return array |
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407 | */ |
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408 | public function getPairAtPosition($pos) |
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413 | |||
414 | /** |
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415 | * Get collection as array. |
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416 | * |
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417 | * @return array This collection as an array |
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418 | */ |
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419 | public function toArray() |
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430 | |||
431 | /** |
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432 | * Get this collection's keys as a collection. |
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433 | * |
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434 | * @return AbstractCollection Containing this collection's keys |
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435 | */ |
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436 | public function keys() |
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440 | |||
441 | /** |
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442 | * Get this collection's values as a collection. |
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443 | * |
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444 | * This method returns this collection's values but completely re-indexed (numerically). |
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445 | * |
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446 | * @return AbstractCollection Containing this collection's values |
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447 | */ |
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448 | public function values() |
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452 | |||
453 | /** |
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454 | * Merge data into collection. |
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455 | * |
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456 | * Merges input data into this collection. Input can be an array or another collection. Returns a NEW collection object. |
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457 | * |
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458 | * @param Traversable|array $data The data to merge with this collection |
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459 | * @return AbstractCollection A new collection with $data merged in |
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460 | */ |
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461 | public function merge($data) |
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470 | |||
471 | /** |
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472 | * Determine if this collection contains a value. |
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473 | * |
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474 | * Allows you to pass in a value or a callback function and optionally an index, |
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475 | * and tells you whether or not this collection contains that value. If the $index param is specified, only that index will be looked under. |
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476 | * |
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477 | * @param mixed|callable $value The value to check for |
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478 | * @param mixed $index The (optional) index to look under |
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479 | * @return boolean True if this collection contains $value |
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480 | * @todo Maybe add $identical param for identical comparison (===) |
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481 | * @todo Allow negative offset for second param |
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482 | */ |
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483 | public function contains($value, $index = null) |
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503 | |||
504 | |||
505 | /** |
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506 | * Get duplicate values. |
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507 | * |
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508 | * Returns a collection of arrays where the key is the duplicate value |
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509 | * and the value is an array of keys from the original collection. |
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510 | * |
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511 | * @return AbstractCollection A new collection with duplicate values. |
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512 | */ |
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513 | public function duplicates() |
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523 | |||
524 | /** |
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525 | * Pop an element off the end of this collection. |
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526 | * |
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527 | * @return mixed The last item in this collectio n |
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528 | */ |
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529 | public function pop() |
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533 | |||
534 | /** |
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535 | * Shift an element off the beginning of this collection. |
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536 | * |
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537 | * @return mixed The first item in this collection |
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538 | */ |
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539 | public function shift() |
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543 | |||
544 | /** |
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545 | * Push a item(s) onto the end of this collection. |
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546 | * |
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547 | * Returns a new collection with $items added. |
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548 | * |
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549 | * @param array $items Any number of arguments will be pushed onto the |
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550 | * @return mixed The first item in this collection |
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551 | */ |
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552 | public function push(...$items) |
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557 | |||
558 | /** |
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559 | * Unshift item(s) onto the beginning of this collection. |
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560 | * |
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561 | * Returns a new collection with $items added. |
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562 | * |
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563 | * @return mixed The first item in this collection |
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564 | */ |
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565 | public function unshift(...$items) |
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570 | |||
571 | /** |
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572 | * Pad this collection to a certain size. |
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573 | * |
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574 | * Returns a new collection, padded to the given size, with the given value. |
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575 | * |
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576 | * @param int $size The number of items that should be in the collection |
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577 | * @param null $with The value to pad the collection with |
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578 | * @return AbstractCollection A new collection padded to specified length |
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579 | */ |
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580 | public function pad($size, $with = null) |
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584 | |||
585 | /** |
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586 | * Apply a callback to each item in collection. |
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587 | * |
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588 | * Applies a callback to each item in collection and returns a new collection |
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589 | * containing each iteration's return value. |
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590 | * |
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591 | * @param callable $callback The callback to apply |
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592 | * @return AbstractCollection A new collection with callback return values |
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593 | */ |
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594 | public function map(callable $callback) |
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598 | |||
599 | /** |
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600 | * Apply a callback to each item in collection. |
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601 | * |
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602 | * Applies a callback to each item in collection. The callback should return |
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603 | * false to filter any item from the collection. |
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604 | * |
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605 | * @param callable $callback The callback function |
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606 | * @param null $extraContext Extra context to pass as third param in callback |
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607 | * @return $this |
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608 | * @see php.net array_walk |
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609 | */ |
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610 | public function walk(callable $callback, $extraContext = null) |
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615 | |||
616 | /** |
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617 | * Iterate over each item that matches criteria in callback |
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618 | * |
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619 | * @param Closure|callable $callback A callback to use |
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620 | * @param object $bindTo The object to bind to |
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621 | * @return AbstractCollection |
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622 | */ |
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623 | public function each(Closure $callback, $bindTo = null) |
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640 | |||
641 | /** |
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642 | * Get each key/value as an array pair |
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643 | * |
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644 | * Returns a collection of arrays where each item in the collection is [key,value] |
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645 | * |
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646 | * @return AbstractCollection |
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647 | */ |
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648 | public function pairs() |
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658 | |||
659 | /** |
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660 | * Reduce the collection to a single value. |
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661 | * |
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662 | * Using a callback function, this method will reduce this collection to a |
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663 | * single value. |
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664 | * |
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665 | * @param callable $callback The callback function used to reduce |
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666 | * @param null $initial The initial carry value |
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667 | * @return mixed The single value produced by reduction algorithm |
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668 | */ |
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669 | public function reduce(callable $callback, $initial = null) |
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673 | |||
674 | /** |
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675 | * Filter the collection. |
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676 | * |
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677 | * Using a callback function, this method will filter out unwanted values, returning |
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678 | * a new collection containing only the values that weren't filtered. |
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679 | * |
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680 | * @param callable $callback The callback function used to filter |
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681 | * @param int $flag array_filter flag(s) (ARRAY_FILTER_USE_KEY or ARRAY_FILTER_USE_BOTH) |
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682 | * @return AbstractCollection A new collection with only values that weren't filtered |
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683 | * @see php.net array_filter |
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684 | */ |
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685 | public function filter(callable $callback, $flag = ARRAY_FILTER_USE_BOTH) |
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689 | |||
690 | /** |
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691 | * Return the first item that meets given criteria. |
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692 | * |
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693 | * Using a callback function, this method will return the first item in the collection |
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694 | * that causes the callback function to return true. |
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695 | * |
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696 | * @param callable $callback The callback function |
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697 | * @return null|mixed The first item in the collection that causes callback to return true |
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698 | */ |
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699 | public function first(callable $callback) |
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708 | |||
709 | /** |
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710 | * Return the last item that meets given criteria. |
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711 | * |
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712 | * Using a callback function, this method will return the last item in the collection |
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713 | * that causes the callback function to return true. |
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714 | * |
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715 | * @param callable $callback The callback function |
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716 | * @return null|mixed The last item in the collection that causes callback to return true |
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717 | */ |
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718 | public function last(callable $callback) |
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723 | |||
724 | /** |
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725 | * Returns collection in reverse order. |
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726 | * |
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727 | * @param null $preserveKeys True if you want to preserve collection's keys |
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728 | * @return AbstractCollection This collection in reverse order. |
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729 | */ |
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730 | public function reverse($preserveKeys = null) |
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734 | |||
735 | /** |
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736 | * Get unique items. |
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737 | * |
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738 | * Returns a collection of all the unique items in this collection. |
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739 | * |
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740 | * @return AbstractCollection This collection with duplicate items removed |
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741 | */ |
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742 | public function unique() |
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746 | |||
747 | /** |
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748 | * Convert collection to string |
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749 | * |
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750 | * @return string A string representation of this collection |
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751 | * @todo Eventually I would like to add a $delim property so that |
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752 | * I can easily join collection items together with a particular |
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753 | * character (or set of characters). I would then add a few methods |
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754 | * to change the delim property. It would default to a comma. |
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755 | */ |
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756 | public function __toString() |
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760 | |||
761 | /** |
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762 | * Join collection together using a delimiter. |
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763 | * |
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764 | * @param string $delimiter The delimiter string/char |
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765 | * |
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766 | * @return string |
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767 | */ |
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768 | public function join($delimiter = '') |
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772 | |||
773 | /** |
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774 | * Counts how many times each value occurs in a collection. |
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775 | * |
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776 | * Returns a new collection with values as keys and how many times that |
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777 | * value appears in the collection. Works best with scalar values but will |
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778 | * attempt to work on collections of objects as well. |
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779 | * |
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780 | * @return AbstractCollection |
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781 | * |
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782 | * @todo Right now, collections of arrays or objects are supported via the |
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783 | * __toString() or spl_object_hash() |
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784 | * @todo NumericCollection::counts() does the same thing... |
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785 | */ |
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786 | public function frequency() |
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809 | |||
810 | /** |
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811 | * Collection factory method. |
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812 | * |
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813 | * This method will analyze input data and determine the most appropriate Collection |
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814 | * class to use. It will then instantiate said Collection class with the given |
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815 | * data and return it. |
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816 | * |
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817 | * @param mixed $data The data to wrap |
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818 | * @return AbstractCollection A collection containing $data |
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819 | */ |
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820 | public static function factory($data = null) |
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835 | |||
836 | /** |
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837 | * Assert input data is of the correct structure |
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838 | * |
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839 | * @param mixed $data Data to check |
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840 | * @throws InvalidArgumentException If invalid data structure |
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841 | */ |
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842 | protected function assertCorrectInputDataType($data) |
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848 | |||
849 | /** |
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850 | * Convert input data to an array. |
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851 | * |
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852 | * Convert the input data to an array that can be worked with by a collection. |
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853 | * |
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854 | * @param mixed $data The input data |
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855 | * @return array |
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856 | */ |
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857 | protected function prepareData($data) |
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861 | |||
862 | /** |
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863 | * Is input data tabular? |
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864 | * |
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865 | * Returns true if input data is tabular in nature. This means that it is a |
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866 | * two-dimensional array with the same keys (columns) for each element (row). |
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867 | * |
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868 | * @param mixed $data The data structure to check |
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869 | * @return boolean True if data structure is tabular |
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870 | */ |
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871 | public static function isTabular($data) |
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897 | |||
898 | /** |
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899 | * Check data for multiple dimensions. |
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900 | * |
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901 | * This method is to determine whether a data structure is multi-dimensional. |
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902 | * That is to say, it is a traversable structure that contains at least one |
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903 | * traversable structure. |
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904 | * |
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905 | * @param mixed $data The input data |
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906 | * @return bool |
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907 | */ |
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908 | public static function isMultiDimensional($data) |
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920 | |||
921 | /** |
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922 | * Determine if structure contains all numeric values. |
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923 | * |
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924 | * @param mixed $data The input data |
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925 | * @return bool |
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926 | */ |
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927 | public static function isAllNumeric($data) |
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939 | |||
940 | /** |
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941 | * Is data a string of characters? |
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942 | * |
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943 | * Just checks to see if input is a string of characters or a string |
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944 | * of digits. |
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945 | * |
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946 | * @param mixed $data Data to check |
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947 | * @return bool |
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948 | */ |
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949 | public static function isCharacterSet($data) |
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956 | |||
957 | /** |
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958 | * Determine whether data is consistent with a given collection type. |
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959 | * |
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960 | * This method is used to determine whether input data is consistent with a |
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961 | * given collection type. For instance, CharCollection requires a string. |
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962 | * NumericCollection requires an array or traversable set of numeric data. |
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963 | * TabularCollection requires a two-dimensional data structure where all the |
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964 | * keys are the same in every row. |
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965 | * |
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966 | * @param mixed $data Data structure to check for consistency |
||
967 | * @return boolean |
||
968 | */ |
||
969 | abstract protected function isConsistentDataStructure($data); |
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970 | |||
971 | } |