import type SdOptGroup from '../optgroup/optgroup.js';
import type SdOption from '../option/option.js';
export declare const getAssignedElementsForSlot: (slot: HTMLSlotElement) => HTMLElement[];
export declare const getOptionOrNestedOptions: (item: HTMLElement) => SdOption | SdOption[];
export declare const isOptgroup: (item: HTMLElement) => item is SdOptGroup;
export declare const getAllOptions: (items: HTMLElement[]) => (SdOption | SdOption[])[];
export declare const filterOnlyOptgroups: (items: HTMLElement[]) => SdOptGroup[];
export declare const normalizeString: (str: string) => string;
