Creates a new vector using a callable to determine which values to include

# Ds\Vector::filter

(PECL ds >= 1.0.0)

Ds\Vector::filter — Creates a new vector using a callable to determine which values to include

### Descrierea

public Ds\Vector::filter ([ callable `$callback` ] ) : Ds\Vector

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

### Parametri

`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.

### Valorile întoarse

A new vector containing all the values for which either the `callback` returned `TRUE`, or all values that convert to `TRUE` if a `callback` was not provided.

### Exemple

Example #1 Ds\Vector::filter() example using callback function

`<?php
$vector = new \Ds\Vector([1, 2, 3, 4, 5]);
var_dump($vector->filter(function($value) {
return $value % 2 == 0;
}));
?>`

Exemplul de mai sus va afișa ceva similar cu:

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

Example #2 Ds\Vector::filter() example without a callback function

`<?php
$vector = new \Ds\Vector([0, 1, 'a', true, false]);
var_dump($vector->filter());
?>`

Exemplul de mai sus va afișa ceva similar cu:

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