import type { Message } from "../types.js";
import type { DescFile } from "../descriptors.js";
import type { GenExtension } from "./types.js";
/**
 * Hydrate an extension descriptor.
 *
 * @private
 */
export declare function extDesc<Extendee extends Message, Value>(file: DescFile, path: number, ...paths: number[]): GenExtension<Extendee, Value>;