PHP - Ds Sequence filter() Function

Ds\Sequence::filter() function can create a new sequence using callable to determine which values to include.

Syntax

public abstract Ds\Sequence Ds\Sequence::filter([ callable $callback ] )

Ds\Sequence::filter() function can return a new sequence containing all values for which either a callback returned true, or all values that convert to true if a callback was not provided.

Example 1

<?php 
   $seq = new \Ds\Vector([10, 20, 30, 40, 50]);
   var_dump($seq->filter(function($val) {
      return $val % 4 == 0; 
   })); 
?>

Example 2

<?php 
   $seq = new \Ds\Vector([2, 3, 5, 7, 9, 10]);
   var_dump($seq->filter(function($val) {
      return $val; 
   })); 
?>