/**
 * Type-ahead support shared by the composite widgets: the collapsed select-only combobox, and the
 * listbox and menu groups.
 */
/**
 * How long, in milliseconds, successive keystrokes keep adding up to one type-ahead prefix.
 */
export const TYPE_AHEAD_TIMEOUT: 500;
/**
 * Keystroke buffer behind type-ahead: printable keys typed in quick succession make up a prefix,
 * which is dropped again after a short pause.
 */
export class TypeAhead {
    /**
     * Add a keystroke to the prefix.
     * @param {string} key Printable key.
     * @returns {string} Current prefix.
     */
    push(key: string): string;
    /**
     * Drop the prefix.
     */
    reset(): void;
    #private;
}
export function findTypeAheadMatch(labels: string[], prefix: string, currentIndex: number): number;