private function prop_get_length():int {
		$key = $this->iteratorKey;

		$length = 0;
		foreach($this as $element) {
			$length++;
		}

		$this->iteratorKey = $key;
		return $length;
	}
private function prop_get_length():int {
		$key = $this->iteratorKey;

		$length = 0;
		foreach($this as $element) {
			$length++;
		}

		$this->iteratorKey = $key;
		return $length;
	}
Returns the number of Elements contained in this Collection. Exposed as the
$length property.
@return int Number of Elements