import { StatusUnionHandler } from '../util/handlers/StatusUnionHandler';
import type { Credentials } from './Credentials';
import type { CredentialsExtractor } from './CredentialsExtractor';
/**
 * Combines the results of several CredentialsExtractors into one.
 * If multiple of these extractors return a value for the same key,
 * the last result will be used.
 */
export declare class UnionCredentialsExtractor extends StatusUnionHandler<CredentialsExtractor> {
    constructor(extractors: CredentialsExtractor[]);
    combine(results: Credentials[]): Promise<Credentials>;
    /**
     * Helper function that makes sure the typings are correct.
     */
    private setValue;
}
