Files whose name does not match a book. */ public array $unmatched = []; /** @var list Files that are neither an ISBN-13 nor a book ID. */ public array $ignored = []; /** @var list Files that could not be stored as covers, with the reason. */ public array $failed = []; public function imported(): int { return $this->ownById + $this->ownByIsbn + $this->byIsbn; } }