import { IndexPath } from './indexPath.js';
import { BaseOptions } from './options.js';
export type ReduceOptions<T, R> = BaseOptions<T> & {
    /**
     * The initial result value.
     */
    initialResult: R;
    /**
     * Return the next result value.
     */
    nextResult: (result: R, node: T, indexPath: IndexPath) => R;
};
export declare function reduce<T, R>(node: T, options: ReduceOptions<T, R>): R;