import { TC39IterableHelpersObject } from "../tests/tc39/sync";
import { FilterFn, ForEachFn, MapFn, ReduceFn, GuardFilterFn } from "../operations/sync";
export interface TC39SyncIteratorHelpers<T> {
    map<O>(mapperFn: MapFn<T, O>): TC39SyncIteratorHelpers<O>;
    filter<Is extends T>(filterFn: GuardFilterFn<T, Is>): TC39SyncIteratorHelpers<Is>;
    filter(filterFn: FilterFn<T>): TC39SyncIteratorHelpers<T>;
    take(limit: number): TC39SyncIteratorHelpers<T>;
    drop(limit: number): TC39SyncIteratorHelpers<T>;
    flatMap<O>(mapperFn: MapFn<T, Iterable<O>>): TC39SyncIteratorHelpers<O>;
    reduce<A>(reduceFn: ReduceFn<T, A>, initial: A): A;
    toArray(): T[];
    forEach(callbackFn: ForEachFn<T>): void;
    some(filterFn: FilterFn<T>): boolean;
    every(filterFn: FilterFn<T>): boolean;
    find(filterFn: FilterFn<T>): T | undefined;
}
declare const TC39SyncIteratorHelpers_base: import("./construct").TC39IteratorHelpersConstructor<object>;
export declare class TC39SyncIteratorHelpers<T> extends TC39SyncIteratorHelpers_base implements TC39IterableHelpersObject<T> {
    constructor();
    [Symbol.iterator](): Iterator<T>;
}
export {};