BetterWay_To_IterateOverACollection.php

<?php  

/**
 *  A better way to iterate over an collection
 */

$itemsArray = [ 1, 2, 3 ];

/**
 * Legacy code
 */
foreach ( $itemsArray as $key => $item ) {
	echo $item;
}

/**
 * A better code
 */
class Items
{
	private $array;

	public function __construct( $array )
	{
		$this->array = $array;
	}
	
	public function each( $cb )
	{
		foreach ( $this->array as $key => $value ) {
			$cb( $key, $value );
		}
	}

	/** More logic can be added here **/	
	public function isEmpty(){}
	public function has( $value ){}
}

$items = new Items( $itemsArray );
$items->each( function( $key, $item ){
	echo $item;
});