/**
 * This function returns a function to generate ids.
 * This can be used to generate unique, but predictable ids to pair labels
 * with their inputs. It takes an optional prefix as a parameter. If you don't
 * specify it, it generates a random id prefix. If you specify a custom prefix
 * it should begin with an letter to be HTML4 compliant.
 */
export declare function htmlIdGenerator(idPrefix?: string): (suffix?: string | undefined) => string;