export declare enum WidgetNamespace {
    BUILTIN = "builtin",
    EXTENSION = "extension",
    SIDEBAR_BUILTIN = "sidebar-builtin",
    APP = "app",
    EDITOR_BUILTIN = "editor-builtin"
}
export declare const DEFAULT_EDITOR_ID = "default-editor";
/**
 * @internal
 */
export declare const in_: <K extends string, O extends object>(key: K, object: O) => key is K & keyof O;