import type { Redis } from 'ioredis';
export declare class Counter {
    private readonly redis;
    private readonly groupKey;
    constructor(redis: Redis, groupKey: string);
    incrOrSet(field: string, num: number, initialNum: number): Promise<number>;
    incrOrSetLazyload(field: string, num: number, initialNumGetter: () => Promise<number>): Promise<number>;
    incr(field: string, num: number): Promise<number>;
    getOne(field: string, defaultVal?: number): Promise<number>;
    getAll(): Promise<Record<string, string>>;
    set(field: string, num: number): Promise<number>;
    exists(field: string): Promise<import("ioredis").BooleanResponse>;
    delete(field: string): Promise<number>;
    mergeTo<T extends {}>(records: T[], counters: Record<string, string>, destField: string, idGetterFn: (record: T) => string, defaultCount?: number): void;
    getAndMergeTo<T>(records: T[], destField: string, idGetterFn: (record: T) => string, defaultCount?: number): Promise<void>;
}