import { PickObject } from "./types";
declare type ObjectLike = {
    [key: string]: unknown;
};
/** get diff */
export declare function diff<T extends ObjectLike, D extends ObjectLike>(source: T, other: D): PickObject<T, D>;
/** From source, pick whose keys are existed in props' keys */
export declare function pickDiffPatch<T extends ObjectLike, D extends ObjectLike>(source: T, props: D): PickObject<T, D>;
/** create diff patch */
export declare function createDiffPatch<T extends ObjectLike, D extends ObjectLike>(source: T, other: D): PickObject<D, PickObject<T, D>>;
/**
 * Get diff patch between source and snapshot.
 *
 * @example
 *
 * const source = { a: 1, b: 2 };
 * const snapshot = new Snapshot(source);
 * source.a = 3;
 * snapshot.getDiffPatch();
 * // => { a: 3 }
 */
export declare class Snapshot<T extends ObjectLike> {
    private _source;
    readonly snapshots: T[];
    private _index;
    constructor(source: T);
    /** push new snaphsot */
    takeSnapshot(): this;
    /** get diff patch between latest source and snapshot */
    getDiffPatch(source?: T, other?: T): PickObject<T, PickObject<T, T>>;
}
export {};