export declare const URL_PLACEHOLDER_REGEXP: RegExp;
export declare const EMAIL_REGEXP: RegExp;
export declare const MAILTO_REGEXP: RegExp;
/**
 * @see https://regex101.com/r/W0NkQE/2
 * For problems, blame Ivan & Lukas :)
 */
export declare const URL_WITHOUT_PROTOCOL_REGEXP: RegExp;
export declare const URL_WITH_PROTOCOL_REGEXP: RegExp;
export declare const URL_WITH_OPTIONAL_PROTOCOL_REGEXP: RegExp;
export declare const HREF_REGEXP: RegExp;
/**
 * Make sure that URLs without protocol automatically get "http://" prefix.
 * @param href
 */
export declare function normalizeHref(href: string): string;
export declare function normalizeMailtoHref(href: string): string;
export declare function matchUrls(content: string): IterableIterator<RegExpMatchArray>;