import { AnyIterable } from "./types";
import { AsyncIterable } from "ix";
export interface GroupedItems<T> {
    readonly key: string;
    readonly items: ReadonlyArray<T>;
}
declare class GroupingProgressDisplay {
    private progress;
    constructor(progress: GroupingProgress);
    toString(): string;
    toJSON(): {
        state: GroupingState;
        groupingBytesPerSecond: number;
        readingBytesPerSecond: number;
        memory: number;
        groupingStartTime: number;
        groupingStopTime: number;
        readingStartTime: number;
        readingStopTime: number;
        groupedItems: number;
        groupedBytes: number;
        groupedGroups: number;
        readedItems: number;
        readedBytes: number;
        readedGroups: number;
    };
}
declare type GroupingState = "READING" | "GROUPING" | "IDLE";
declare class GroupingProgress {
    groupedBytes: number;
    groupedItems: number;
    groupedGroups: number;
    readedBytes: number;
    readedGroups: number;
    readedItems: number;
    state: GroupingState;
    parsingStartTime: number;
    parsingStopTime: number;
    readingStartTime: number;
    readingStopTime: number;
    start(action: GroupingState): void;
    stop(action: GroupingState): void;
    constructor();
    addChunk(chunk: number): void;
    addGroup(group: number): void;
    addItem(count?: number): void;
    readChunk(chunk: number): void;
    readGroup(group: number): void;
    readItem(count?: number): void;
    set(data: {
        currentSize?: number;
        items?: number;
    }): void;
}
export interface FileGroupByOptions<T> {
    source: AnyIterable<T>;
    groupingFn: (data: T) => number | string;
    progress?: (progress: GroupingProgressDisplay) => void;
    progressFrequency?: number;
}
export declare function fileGroupBy<T>(args: FileGroupByOptions<T>): AsyncIterable<GroupedItems<T>>;
export {};
//# sourceMappingURL=fileGroupBy.d.ts.map