/**
* @license Copyright (c) 2003-2026, CKSource Holding sp. z o.o. All rights reserved.
* For licensing, see LICENSE.md or https://ckeditor.com/legal/ckeditor-licensing-options
*/
/**
* @module utils/first
*/
/**
* Returns first item of the given `iterator`.
*/
export declare function first<T>(iterator: Iterator<T>): T | null;