import { AsyncIterable } from "ix";
import { GroupedItems } from "./fileGroupBy";
import { AnyIterable } from "./types";
export interface TrailingGroupByArgs<T> {
    groupBy: ((data: T) => string | number) | ((data: T) => Promise<string | number>);
    maxGroupSize: number;
    totalItemsInMemory: number;
}
export declare function trailingGroupBy<T>(args: TrailingGroupByArgs<T>): (data: AnyIterable<T>) => AsyncIterable<GroupedItems<T>>;
export declare function trailingGroupBy<T>(data: AnyIterable<T>, args: TrailingGroupByArgs<T>): AsyncIterable<GroupedItems<T>>;
export interface TrailingMapArgs<T, R> {
    mapFunc: (data: T) => Promise<R>;
    maxConcurrency: number;
}
export declare function trailingMap<T, R>(args: TrailingMapArgs<T, R>): (data: AnyIterable<T>) => AsyncIterable<R>;
export declare function trailingMap<T, R>(data: AnyIterable<T>, args: TrailingMapArgs<T, R>): AsyncIterable<R>;
export declare function onDone<T>(callback: () => void): (data: AnyIterable<T>) => AsyncIterable<T>;
export declare function onDone<T>(data: AnyIterable<T>, callback: () => void): AsyncIterable<T>;
declare class ProgressTrack {
    items: number;
    isRunning: boolean;
    startTime: number;
    rollingDurations: number[];
    addItem(): void;
    get average(): number;
}
declare class Progress {
    private progress;
    constructor(progress: ProgressTrack);
    toString(): string;
    toJSON(): {
        speed: number;
        items: number;
    };
}
interface OnProgressArgs {
    progress: (data: Progress) => void;
    progressFrequency?: number;
}
export declare function onProgress<T>(args: OnProgressArgs): (data: AnyIterable<T>) => AsyncIterable<T>;
export declare function onProgress<T>(data: AnyIterable<T>, args: OnProgressArgs): AsyncIterable<T>;
export {};
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