reset() method may not work as you expect with ArrayAccess objects.
Using reset($myArrayAccessObject) returns the first property from $myArrayAccessObject, not the first item in the items array.
If you want to use the reset() method to return the first array item, then you can use the following simple workaround:
<?php
class MyArrayAccessObject implements Iterator, ArrayAccess, Countable {
 protected $first = null; //WARNING! Keep this always first.
 protected $items = null;
 private function supportReset() {
 $this->first = reset($this->items); //Support reset().
 }
 // ...
 public function offsetSet($offset, $value) {
 if ($offset === null) {
 $this->items[] = $value;
 }
 else {
 $this->items[$offset] = $value;
 }
 $this->supportReset();
 }
}
?>

Finally, call $this->supportReset() in the end of all methods that change the internal $items array, such as in offsetSet(), offsetUnset() etc.
This way, you can use the reset() method as normally:
<?php
$firstArrayItem = reset($myArrayAccessObject);
?>