(PECL ds >= 1.0.0)
Ds\Map::intersect — Creates a new map by intersecting keys with another map
Creates a new map containing the pairs of the current instance whose keys are also present in the given map. In other words, returns a copy of the current instance with all keys removed that are not also in the other map.
A ∩ B = {x : x ∈ A ∧ x ∈ B}
Hinweis:
Values from the current instance will be kept.
mapThe other map, containing the keys to intersect with.
The key intersection of the current instance and another map.
Beispiel #1 Ds\Map::intersect() example
<?php
$a = new \Ds\Map(["a" => 1, "b" => 2, "c" => 3]);
$b = new \Ds\Map(["b" => 4, "c" => 5, "d" => 6]);
var_dump($a->intersect($b));
?>Das oben gezeigte Beispiel erzeugt eine ähnliche Ausgabe wie:
object(Ds\Map)#3 (2) { [0]=> object(Ds\Pair)#4 (2) { ["key"]=> string(1) "b" ["value"]=> int(2) } [1]=> object(Ds\Pair)#5 (2) { ["key"]=> string(1) "c" ["value"]=> int(3) } }