public function lastIndexOf( $sequence, $fromIndex = 0, $ignoreCase = false ) {
		if ( $fromIndex < 0 ) {
			$fromIndex = 0;
		} else if ( $fromIndex >= $this->length() ) {
			return - 1;
		}
		if ( $ignoreCase == false ) {
			$index = strrpos( $this->value, $sequence, $fromIndex );
		} else {
			$index = strripos( $this->value, $sequence, $fromIndex );
		}

		return $index === false ? - 1 : $index;
	}