interface PurlObject {
    name: string;
    namespace?: string | undefined;
    qualifiers?: Record<string, string> | undefined;
    subpath?: string | undefined;
    type?: string | undefined;
    version?: string | undefined;
}
/**
 * Normalize QPKG package URL.
 * Lowercases namespace only.
 */
export declare function normalize(purl: PurlObject): PurlObject;
export {};