import { AsyncIterableX } from '../../asynciterable/asynciterablex';
/**
 * @ignore
 */
export declare function findIndexProto<T>(this: AsyncIterableX<T>, predicate: (value: T, index: number) => boolean | Promise<boolean>, thisArg?: any): Promise<number>;
declare module '../../asynciterable/asynciterablex' {
    interface AsyncIterableX<T> {
        findIndex: typeof findIndexProto;
    }
}