Ds\Map::intersect
Ds\Map::intersect
(PECL ds >= 1.0.0)
Ds\Map::intersect — Creates a new map by intersecting keys with another map.
Description
public Ds\Map Ds\Map::intersect ( Ds\Map $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}
Note:
Values from the current instance will be kept.
Parameters
-
map -
The other map, containing the keys to intersect with.
Return Values
The key intersection of the current instance and another map.
See Also
- » Intersection on Wikipedia
Examples
Example #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)); ?>
The above example will output something similar to:
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)
}
}
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Licensed under the Creative Commons Attribution License v3.0 or later.
https://secure.php.net/manual/en/ds-map.intersect.php
