export declare type Options = {
    protocol?: string;
    hostname?: string;
    registry?: string;
};
export declare function getNpmVersion(pkgName: string, options?: Options): Promise<string | null>;
export declare function getNpmVersions(pkgName: string, options?: Options): Promise<string[]>;
declare function npmVersionCheck(pkgName: string, v: string, options?: {
    protocol?: string;
    hostname?: string;
}): Promise<boolean>;
export default npmVersionCheck;