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