| 1 |  |  | <?php | 
            
                                                                                                            
                            
            
                                    
            
            
                | 2 |  |  | namespace Ds; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 3 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 4 |  |  | use Error; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 5 |  |  | use OutOfBoundsException; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 6 |  |  | use OutOfRangeException; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 7 |  |  | use Traversable; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 8 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 9 |  |  | /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 10 |  |  |  * Set | 
            
                                                                                                            
                            
            
                                    
            
            
                | 11 |  |  |  * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 12 |  |  |  * @package Ds | 
            
                                                                                                            
                            
            
                                    
            
            
                | 13 |  |  |  */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 14 |  |  | final class Set implements \IteratorAggregate, \ArrayAccess, Collection | 
            
                                                                                                            
                            
            
                                    
            
            
                | 15 |  |  | { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 16 |  |  |     use Traits\Collection; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 17 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 18 |  |  |     const MIN_CAPACITY = Map::MIN_CAPACITY; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 19 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 20 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 21 |  |  |      * @var Map | 
            
                                                                                                            
                            
            
                                    
            
            
                | 22 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 23 |  |  |     private $internal; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 24 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 25 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 26 |  |  |      * Creates a new set using the values of an array or Traversable object. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 27 |  |  |      * The keys of either will not be preserved. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 28 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 29 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 30 |  |  |      * Should an integer be provided the Set will allocate the memory capacity | 
            
                                                                                                            
                            
            
                                    
            
            
                | 31 |  |  |      * to the size of $values. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 32 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 33 |  |  |      * @param array|\Traversable|int|null $values | 
            
                                                                                                            
                            
            
                                    
            
            
                | 34 |  |  |      */ | 
            
                                                                                                            
                            
            
                                                                    
                                                                                                        
            
            
                | 35 |  | View Code Duplication |     public function __construct($values = null) | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                                                                            
                            
            
                                    
            
            
                | 36 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 37 |  |  |         $this->internal = new Map(); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 38 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 39 |  |  |         if (is_array($values) || $values instanceof Traversable) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 40 |  |  |             $this->addAll($values); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 41 |  |  |         } elseif (is_integer($values)) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 42 |  |  |             $this->allocate($values); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 43 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 44 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 45 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 46 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 47 |  |  |      * Adds zero or more values to the set. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 48 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 49 |  |  |      * @param mixed ...$values | 
            
                                                                                                            
                            
            
                                    
            
            
                | 50 |  |  |      */ | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                                                                            
                            
            
                                    
            
            
                | 51 |  |  |     public function add(...$values) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 52 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 53 |  |  |         foreach ($values as $value) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 54 |  |  |             $this->internal[$value] = null; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 55 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 56 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 57 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 58 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 59 |  |  |      * Adds all values in an array or iterable object to the set. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 60 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 61 |  |  |      * @param array|\Traversable $values | 
            
                                                                                                            
                            
            
                                    
            
            
                | 62 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 63 |  |  |     public function addAll($values) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 64 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 65 |  |  |         if ($values) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 66 |  |  |             foreach ($values as $value) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 67 |  |  |                 $this->internal[$value] = null; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 68 |  |  |             } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 69 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 70 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 71 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 72 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 73 |  |  |      * Ensures that enough memory is allocated for a specified capacity. This | 
            
                                                                                                            
                            
            
                                    
            
            
                | 74 |  |  |      * potentially reduces the number of reallocations as the size increases. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 75 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 76 |  |  |      * @param int $capacity The number of values for which capacity should be | 
            
                                                                                                            
                            
            
                                    
            
            
                | 77 |  |  |      *                      allocated. Capacity will stay the same if this value | 
            
                                                                                                            
                            
            
                                    
            
            
                | 78 |  |  |      *                      is less than or equal to the current capacity. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 79 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 80 |  |  |     public function allocate(int $capacity) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 81 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 82 |  |  |         $this->internal->allocate($capacity); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 83 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 84 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 85 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 86 |  |  |      * Returns the current capacity of the set. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 87 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 88 |  |  |      * @return int | 
            
                                                                                                            
                            
            
                                    
            
            
                | 89 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 90 |  |  |     public function capacity(): int | 
            
                                                                                                            
                            
            
                                    
            
            
                | 91 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 92 |  |  |         return $this->internal->capacity(); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 93 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 94 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 95 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 96 |  |  |      * Clear all elements in the Set | 
            
                                                                                                            
                            
            
                                    
            
            
                | 97 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 98 |  |  |     public function clear() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 99 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 100 |  |  |         $this->internal->clear(); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 101 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 102 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 103 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 104 |  |  |      * Determines whether the set contains all of zero or more values. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 105 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 106 |  |  |      * @param mixed ...$values | 
            
                                                                                                            
                            
            
                                    
            
            
                | 107 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 108 |  |  |      * @return bool true if at least one value was provided and the set | 
            
                                                                                                            
                            
            
                                    
            
            
                | 109 |  |  |      *              contains all given values, false otherwise. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 110 |  |  |      */ | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                                                                            
                            
            
                                                                    
                                                                                                        
            
            
                | 111 |  | View Code Duplication |     public function contains(...$values): bool | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                                                                            
                            
            
                                    
            
            
                | 112 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 113 |  |  |         if ( ! $values) { | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                                                                            
                            
            
                                    
            
            
                | 114 |  |  |             return false; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 115 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 116 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 117 |  |  |         foreach ($values as $value) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 118 |  |  |             if ( ! $this->internal->containsKey($value)) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 119 |  |  |                 return false; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 120 |  |  |             } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 121 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 122 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 123 |  |  |         return true; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 124 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 125 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 126 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 127 |  |  |      * @inheritDoc | 
            
                                                                                                            
                            
            
                                    
            
            
                | 128 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 129 |  |  |     public function copy() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 130 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 131 |  |  |         return new Set($this); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 132 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 133 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 134 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 135 |  |  |      * Returns the number of elements in the Stack | 
            
                                                                                                            
                            
            
                                    
            
            
                | 136 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 137 |  |  |      * @return int | 
            
                                                                                                            
                            
            
                                    
            
            
                | 138 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 139 |  |  |     public function count(): int | 
            
                                                                                                            
                            
            
                                    
            
            
                | 140 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 141 |  |  |         return count($this->internal); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 142 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 143 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 144 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 145 |  |  |      * Creates a new set using values from this set that aren't in another set. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 146 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 147 |  |  |      * Formally: A \ B = {x ∈ A | x ∉ B} | 
            
                                                                                                            
                            
            
                                    
            
            
                | 148 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 149 |  |  |      * @param Set $set | 
            
                                                                                                            
                            
            
                                    
            
            
                | 150 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 151 |  |  |      * @return Set | 
            
                                                                                                            
                            
            
                                    
            
            
                | 152 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 153 |  |  |     public function diff(Set $set): Set | 
            
                                                                                                            
                            
            
                                    
            
            
                | 154 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 155 |  |  |         $diff = new Set(); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 156 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 157 |  |  |         foreach ($this as $value) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 158 |  |  |             if ($set->contains($value)) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 159 |  |  |                 continue; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 160 |  |  |             } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 161 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 162 |  |  |             $diff->add($value); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 163 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 164 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 165 |  |  |         return $diff; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 166 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 167 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 168 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 169 |  |  |      * Creates a new set using values in either this set or in another set, | 
            
                                                                                                            
                            
            
                                    
            
            
                | 170 |  |  |      * but not in both. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 171 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 172 |  |  |      * Formally: A ⊖ B = {x : x ∈ (A \ B) ∪ (B \ A)} | 
            
                                                                                                            
                            
            
                                    
            
            
                | 173 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 174 |  |  |      * @param Set $set | 
            
                                                                                                            
                            
            
                                    
            
            
                | 175 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 176 |  |  |      * @return Set | 
            
                                                                                                            
                            
            
                                    
            
            
                | 177 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 178 |  |  |     public function xor(Set $set): Set | 
            
                                                                                                            
                            
            
                                    
            
            
                | 179 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 180 |  |  |         return $this->internal->xor($set->internal)->keys(); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 181 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 182 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 183 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 184 |  |  |      * Returns a new set containing only the values for which a predicate | 
            
                                                                                                            
                            
            
                                    
            
            
                | 185 |  |  |      * returns true. A boolean test will be used if a predicate is not provided. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 186 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 187 |  |  |      * @param callable|null $predicate Accepts a value, returns a boolean: | 
            
                                                                                                            
                            
            
                                    
            
            
                | 188 |  |  |      *                                 true : include the value, | 
            
                                                                                                            
                            
            
                                    
            
            
                | 189 |  |  |      *                                 false: skip the value. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 190 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 191 |  |  |      * @return Set | 
            
                                                                                                            
                            
            
                                    
            
            
                | 192 |  |  |      */ | 
            
                                                                                                            
                            
            
                                                                    
                                                                                                        
            
            
                | 193 |  | View Code Duplication |     public function filter(callable $predicate = null): Set | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                                                                            
                            
            
                                    
            
            
                | 194 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 195 |  |  |         $filtered = new Set(); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 196 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 197 |  |  |         foreach ($this as $value) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 198 |  |  |             if ($predicate ? $predicate($value) : $value) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 199 |  |  |                 $filtered->add($value); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 200 |  |  |             } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 201 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 202 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 203 |  |  |         return $filtered; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 204 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 205 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 206 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 207 |  |  |      * Returns the first value in the set. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 208 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 209 |  |  |      * @return mixed the first value in the set. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 210 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 211 |  |  |     public function first() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 212 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 213 |  |  |         return $this->internal->first()->key; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 214 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 215 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 216 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 217 |  |  |      * Returns the value at a specified position in the set. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 218 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 219 |  |  |      * @param int $position | 
            
                                                                                                            
                            
            
                                    
            
            
                | 220 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 221 |  |  |      * @return mixed|null | 
            
                                                                                                            
                            
            
                                    
            
            
                | 222 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 223 |  |  |      * @throws OutOfRangeException | 
            
                                                                                                            
                            
            
                                    
            
            
                | 224 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 225 |  |  |     public function get(int $position) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 226 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 227 |  |  |         return $this->internal->skip($position)->key; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 228 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 229 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 230 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 231 |  |  |      * Creates a new set using values common to both this set and another set. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 232 |  |  |      * In other words, returns a copy of this set with all values removed that | 
            
                                                                                                            
                            
            
                                    
            
            
                | 233 |  |  |      * aren't in the other set. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 234 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 235 |  |  |      * Formally: A ∩ B = {x : x ∈ A ∧ x ∈ B} | 
            
                                                                                                            
                            
            
                                    
            
            
                | 236 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 237 |  |  |      * @param Set $set | 
            
                                                                                                            
                            
            
                                    
            
            
                | 238 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 239 |  |  |      * @return Set | 
            
                                                                                                            
                            
            
                                    
            
            
                | 240 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 241 |  |  |     public function intersect(Set $set): Set | 
            
                                                                                                            
                            
            
                                    
            
            
                | 242 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 243 |  |  |         return $this->internal->intersect($set->internal)->keys(); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 244 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 245 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 246 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 247 |  |  |      * @inheritDoc | 
            
                                                                                                            
                            
            
                                    
            
            
                | 248 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 249 |  |  |     public function isEmpty(): bool | 
            
                                                                                                            
                            
            
                                    
            
            
                | 250 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 251 |  |  |         return $this->internal->isEmpty(); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 252 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 253 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 254 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 255 |  |  |      * Joins all values of the set into a string, adding an optional 'glue' | 
            
                                                                                                            
                            
            
                                    
            
            
                | 256 |  |  |      * between them. Returns an empty string if the set is empty. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 257 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 258 |  |  |      * @param string $glue | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                                                                            
                            
            
                                    
            
            
                | 259 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 260 |  |  |      * @return string | 
            
                                                                                                            
                            
            
                                    
            
            
                | 261 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 262 |  |  |     public function join(string $glue = null): string | 
            
                                                                                                            
                            
            
                                    
            
            
                | 263 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 264 |  |  |         return implode($glue, $this->toArray()); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 265 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 266 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 267 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 268 |  |  |      * Returns the last value in the set. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 269 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 270 |  |  |      * @return mixed the last value in the set. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 271 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 272 |  |  |     public function last() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 273 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 274 |  |  |         return $this->internal->last()->key; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 275 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 276 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 277 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 278 |  |  |      * Iteratively reduces the set to a single value using a callback. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 279 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 280 |  |  |      * @param callable $callback Accepts the carry and current value, and | 
            
                                                                                                            
                            
            
                                    
            
            
                | 281 |  |  |      *                           returns an updated carry value. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 282 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 283 |  |  |      * @param mixed|null $initial Optional initial carry value. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 284 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 285 |  |  |      * @return mixed The carry value of the final iteration, or the initial | 
            
                                                                                                            
                            
            
                                    
            
            
                | 286 |  |  |      *               value if the set was empty. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 287 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 288 |  |  |     public function reduce(callable $callback, $initial = null) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 289 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 290 |  |  |         $carry = $initial; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 291 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 292 |  |  |         foreach ($this as $value) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 293 |  |  |             $carry = $callback($carry, $value); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 294 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 295 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 296 |  |  |         return $carry; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 297 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 298 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 299 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 300 |  |  |      * Removes zero or more values from the set. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 301 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 302 |  |  |      * @param mixed ...$values | 
            
                                                                                                            
                                                                
            
                                    
            
            
                | 303 |  |  |      */ | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                                        
                            
            
                                    
            
            
                | 304 |  |  |     public function remove(...$values) | 
            
                                                                        
                            
            
                                    
            
            
                | 305 |  |  |     { | 
            
                                                                        
                            
            
                                    
            
            
                | 306 |  |  |         foreach ($values as $value) { | 
            
                                                                        
                            
            
                                    
            
            
                | 307 |  |  |             $this->internal->remove($value, null); | 
            
                                                                        
                            
            
                                    
            
            
                | 308 |  |  |         } | 
            
                                                                        
                            
            
                                    
            
            
                | 309 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 310 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 311 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 312 |  |  |      * Returns a reversed copy of the set. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 313 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 314 |  |  |      * @return Set | 
            
                                                                                                            
                            
            
                                    
            
            
                | 315 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 316 |  |  |     public function reverse(): Set | 
            
                                                                                                            
                            
            
                                    
            
            
                | 317 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 318 |  |  |         $reversed = new Set(); | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                                                                            
                            
            
                                    
            
            
                | 319 |  |  |         $reversed->internal = $this->internal->reverse(); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 320 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 321 |  |  |         return $reversed; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 322 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 323 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 324 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 325 |  |  |      * Returns a subset of a given length starting at a specified offset. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 326 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 327 |  |  |      * @param int $offset If the offset is non-negative, the set will start | 
            
                                                                                                            
                            
            
                                    
            
            
                | 328 |  |  |      *                    at that offset in the set. If offset is negative, | 
            
                                                                                                            
                            
            
                                    
            
            
                | 329 |  |  |      *                    the set will start that far from the end. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 330 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 331 |  |  |      * @param int $length If a length is given and is positive, the resulting | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                                                                            
                            
            
                                    
            
            
                | 332 |  |  |      *                    set will have up to that many values in it. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 333 |  |  |      *                    If the requested length results in an overflow, only | 
            
                                                                                                            
                            
            
                                    
            
            
                | 334 |  |  |      *                    values up to the end of the set will be included. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 335 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 336 |  |  |      *                    If a length is given and is negative, the set | 
            
                                                                                                            
                            
            
                                    
            
            
                | 337 |  |  |      *                    will stop that many values from the end. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 338 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 339 |  |  |      *                    If a length is not provided, the resulting set | 
            
                                                                                                            
                            
            
                                    
            
            
                | 340 |  |  |      *                    will contains all values between the offset and the | 
            
                                                                                                            
                            
            
                                    
            
            
                | 341 |  |  |      *                    end of the set. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 342 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 343 |  |  |      * @return Set | 
            
                                                                                                            
                            
            
                                    
            
            
                | 344 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 345 |  |  |     public function slice(int $offset, int $length = null): Set | 
            
                                                                                                            
                            
            
                                    
            
            
                | 346 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 347 |  |  |         $sliced = new Set(); | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                                                                            
                            
            
                                    
            
            
                | 348 |  |  |         $sliced->internal = $this->internal->slice($offset, $length); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 349 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 350 |  |  |         return $sliced; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 351 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 352 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 353 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 354 |  |  |      * Returns a sorted copy of the set, based on an optional callable | 
            
                                                                                                            
                            
            
                                    
            
            
                | 355 |  |  |      * comparator. Natural ordering will be used if a comparator is not given. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 356 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 357 |  |  |      * @param callable|null $comparator Accepts two values to be compared. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 358 |  |  |      *                                  Should return the result of a <=> b. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 359 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 360 |  |  |      * @return Set | 
            
                                                                                                            
                            
            
                                    
            
            
                | 361 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 362 |  |  |     public function sort(callable $comparator = null): Set | 
            
                                                                                                            
                            
            
                                    
            
            
                | 363 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 364 |  |  |         $set = new Set(); | 
                            
                    |  |  |  | 
                                                                                        
                                                                                     | 
            
                                                                                                            
                            
            
                                    
            
            
                | 365 |  |  |         $set->internal = $this->internal->sort($comparator); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 366 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 367 |  |  |         return $set; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 368 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 369 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 370 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 371 |  |  |      * @inheritDoc | 
            
                                                                                                            
                            
            
                                    
            
            
                | 372 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 373 |  |  |     public function toArray(): array | 
            
                                                                                                            
                            
            
                                    
            
            
                | 374 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 375 |  |  |         return iterator_to_array($this); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 376 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 377 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 378 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 379 |  |  |      * Creates a new set that contains the values of this set as well as the | 
            
                                                                                                            
                            
            
                                    
            
            
                | 380 |  |  |      * values of another set. | 
            
                                                                                                            
                            
            
                                    
            
            
                | 381 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 382 |  |  |      * Formally: A ∪ B = {x: x ∈ A ∨ x ∈ B} | 
            
                                                                                                            
                            
            
                                    
            
            
                | 383 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 384 |  |  |      * @param Set $set | 
            
                                                                                                            
                            
            
                                    
            
            
                | 385 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 386 |  |  |      * @return Set | 
            
                                                                                                            
                            
            
                                    
            
            
                | 387 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 388 |  |  |     public function union(Set $set): Set | 
            
                                                                                                            
                            
            
                                    
            
            
                | 389 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 390 |  |  |         $union = new Set(); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 391 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 392 |  |  |         foreach ($this as $value) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 393 |  |  |             $union->add($value); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 394 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 395 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 396 |  |  |         foreach ($set as $value) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 397 |  |  |             $union->add($value); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 398 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 399 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 400 |  |  |         return $union; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 401 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 402 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 403 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 404 |  |  |      * Get iterator | 
            
                                                                                                            
                            
            
                                    
            
            
                | 405 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 406 |  |  |     public function getIterator() | 
            
                                                                                                            
                            
            
                                    
            
            
                | 407 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 408 |  |  |         foreach ($this->internal as $key => $value) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 409 |  |  |             yield $key; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 410 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 411 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 412 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 413 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 414 |  |  |      * @inheritdoc | 
            
                                                                                                            
                            
            
                                    
            
            
                | 415 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 416 |  |  |      * @throws OutOfBoundsException | 
            
                                                                                                            
                            
            
                                    
            
            
                | 417 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 418 |  |  |     public function offsetSet($offset, $value) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 419 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 420 |  |  |         if ($offset === null) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 421 |  |  |             $this->add($value); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 422 |  |  |             return; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 423 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 424 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 425 |  |  |         throw new OutOfBoundsException(); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 426 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 427 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 428 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 429 |  |  |      * @inheritdoc | 
            
                                                                                                            
                            
            
                                    
            
            
                | 430 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 431 |  |  |     public function offsetGet($offset) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 432 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 433 |  |  |         return $this->internal->skip($offset)->key; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 434 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 435 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 436 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 437 |  |  |      * @inheritdoc | 
            
                                                                                                            
                            
            
                                    
            
            
                | 438 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 439 |  |  |      * @throws Error | 
            
                                                                                                            
                            
            
                                    
            
            
                | 440 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 441 |  |  |     public function offsetExists($offset) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 442 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 443 |  |  |         throw new Error(); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 444 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 445 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 446 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 447 |  |  |      * @inheritdoc | 
            
                                                                                                            
                            
            
                                    
            
            
                | 448 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 449 |  |  |      * @throws Error | 
            
                                                                                                            
                            
            
                                    
            
            
                | 450 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 451 |  |  |     public function offsetUnset($offset) | 
            
                                                                                                            
                            
            
                                    
            
            
                | 452 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 453 |  |  |         throw new Error(); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 454 |  |  |     } | 
            
                                                                                                            
                                                                
            
                                    
            
            
                | 455 |  |  | } | 
            
                                                        
            
                                    
            
            
                | 456 |  |  |  | 
            
                        
Duplicated code is one of the most pungent code smells. If you need to duplicate the same code in three or more different places, we strongly encourage you to look into extracting the code into a single class or operation.
You can also find more detailed suggestions in the “Code” section of your repository.