type BasePropertyDescriptor = Pick<PropertyDescriptor, 'configurable' | 'enumerable' | 'writable'>;
type PropertyDescriptorTyped<T> = BasePropertyDescriptor & ({
    value: T;
} | {
    get: () => T;
    set?: (value: T) => void;
});
type ExtensionMap<T extends object> = {
    [K in keyof T]: PropertyDescriptorTyped<T[K]>;
};
/** Type-safe version of `Object.defineProperties` */
export declare function extendObject<T extends object, TExtension extends object>(base: T, extensionDescriptorsMap: ExtensionMap<TExtension>): T & TExtension;
export {};