import { type Timezone } from '../timezone/timezones.js';
import { type FullDate } from './full-date-shape.js';
/**
 * Asserts that the input is a valid {@link FullDate}.
 *
 * @category Assertion
 * @throws An Error if the input is not a valid {@link FullDate}.
 */
export declare function assertValidFullDate(input: unknown): asserts input is FullDate;
/**
 * Checks and type guards that the input is a valid {@link FullDate}.
 *
 * @category Assertion
 */
export declare function isValidFullDate(input: unknown): input is FullDate;
/**
 * Checks and type guards that the given {@link FullDate} instance has the given timezone.
 *
 * @category Assertion
 */
export declare function hasTimezone<const SpecificTimezone extends Timezone>(input: FullDate, timezone: SpecificTimezone): input is FullDate<SpecificTimezone>;