src/TypedArray.php
public function &offsetGet($offset)
	{
		if (!$this->offsetExists($offset)) {
			//	Be sure offset exists before accessing it.
			$this->offsetSet($offset, null);

			//	Returns new offset created by ::offsetSet().
			if (null === $offset) {
				end($this->_container);
				$offset = key($this->_container);
			}
		}

		return $this->_container[$offset];
	}
public function &offsetGet($offset)
	{
		if (!$this->offsetExists($offset)) {
			//	Be sure offset exists before accessing it.
			$this->offsetSet($offset, null);

			//	Returns new offset created by ::offsetSet().
			if (null === $offset) {
				end($this->_container);
				$offset = key($this->_container);
			}
		}

		return $this->_container[$offset];
	}
Required by the ArrayAccess interface.
Returns reference to offset.

http://stackoverflow.com/questions/20053269/indirect-modification-of-overloaded-element-of-splfixedarray-has-no-effect

@param string|int $offset

@return mixed