Ds\Set::filter
(PECL ds >= 1.0.0)
Ds\Set::filter — Creates a new set using a callable to determine which values to include
Beschreibung
Creates a new set using a callable to determine which values to include.
Parameter-Liste
-
callback
-
Optional callable which returns
true
if the value should be included,false
otherwise.If a callback is not provided, only values which are
true
(see converting to boolean) will be included.
Rückgabewerte
A new set containing all the values for which
either the callback
returned true
, or all values that
convert to true
if a callback
was not provided.
Beispiele
Beispiel #1 Ds\Set::filter() example using callback function
<?php
$set = new \Ds\Set([1, 2, 3, 4, 5]);
var_dump($set->filter(function($value) {
return $value % 2 == 0;
}));
?>
Das oben gezeigte Beispiel erzeugt eine ähnliche Ausgabe wie:
object(Ds\Set)#3 (2) { [0]=> int(2) [1]=> int(4) }
Beispiel #2 Ds\Set::filter() example without a callback function
<?php
$set = new \Ds\Set([0, 1, 'a', true, false]);
var_dump($set->filter());
?>
Das oben gezeigte Beispiel erzeugt eine ähnliche Ausgabe wie:
object(Ds\Set)#2 (3) { [0]=> int(1) [1]=> string(1) "a" [2]=> bool(true) }