Iterable group of typed objects, can be easily refactored to only allow scalars.

IterableGroupOfTypedObjects.php

<?php
namespace Model\User\UserItem;

/**
 * Iterable group of UserItems
 */
class Group implements \Iterator {

    private $position = 0;

    private $objects = array();

    private $size = 0;

    public function __construct() {
    	$this->rewind();
    }

    /* ▼ CUSTOM METHODS ....................................................... */

    /**
     * Adds an item to the group
     * @param \Model\User\UserItem $userItem
     */
    public function add(\Model\User\UserItem $userItem) {
    	$this->objects[]=$userItem;
    	$this->size++;
    }

    /**
     * Returns the user item at the position specified
     * @param int $idx index number to retrieve, null to get the current one
     * @throws \Exception
     * @return \Model\User\UserItem:
     */
    public function get($idx=null) {
        if ($idx === null) return current();
        if(!$this->valid($idx)) throw new \Exception("Index not found");
        return $this->objects[$idx];
    }

    /**
     * Returns the group size
     * @return int
     */
    function size() {
        return $this->size;
    }

    /**
     * Is the group empty?
     * @return boolean
     */
    function isEmpty() {
        if ($this->size()===0) return true;
        return false;
    }

    /* ▼ INTERFACE IMPLEMENTATION ....................................................... */

    /**
     * @see Iterator::current()
     * @return \Model\User\UserItem
     */
    function current() {
    	return $this->objects[$this->position];
    }

    function rewind() {
    	$this->position = 0;
    }

    function key() {
    	return $this->position;
    }

    function next() {
    	++$this->position;
    }

    function valid() {
    	return isset($this->objects[$this->position]);
    }
}