import type { Options as DeepmergeOptions } from 'deepmerge';
import type { BaseDecorator, BaseInterface } from '../Base/types.js';
import type { Base, BaseConfig } from '../Base/index.js';
/**
 * Extends the configuration of an existing class.
 * @link https://js-toolkit.studiometa.dev/api/decorators/withExtraConfig.html
*/
export declare function withExtraConfig<S extends Base>(BaseClass: typeof Base, config: Partial<BaseConfig>, options?: DeepmergeOptions): BaseDecorator<BaseInterface, S>;