Ds\Set::filter

(PECL ds >= 1.0.0)

Ds\Set::filter Creates a new set using a callable to determine which values to include

説明

publicDs\Set::filter(callable$callback = ?): Ds\Set

Creates a new set using a callable to determine which values to include.

パラメータ

callback

callback(mixed$value): bool

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.

返り値

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.

例1 Ds\Set::filter() example using callback function

<?php
$set 
= new \Ds\Set([12345]);

var_dump($set->filter(function($value) {
    return 
$value == 0;
}));
?>

上の例の出力は、 たとえば以下のようになります。

object(Ds\Set)#3 (2) { [0]=> int(2) [1]=> int(4)
}

例2 Ds\Set::filter() example without a callback function

<?php
$set 
= new \Ds\Set([01'a'truefalse]);

var_dump($set->filter());
?>

上の例の出力は、 たとえば以下のようになります。

object(Ds\Set)#2 (3) { [0]=> int(1) [1]=> string(1) "a" [2]=> bool(true)
}