/**
 * Checks if a given string email-like
 *
 * @param {string} email
 * @return {boolean}
 */
export declare function isEmail(email: string): boolean;
/**
 * Checks if a given string satisfies the namespace rules for the VCS host.
 * GitLab additionally allows dotted names and nested groups (`group/subgroup`);
 * github/bitbucket accept a single slug.
 *
 * @param {string} ns
 * @param {string} [provider] - vcs provider id (defaults to the strict slug)
 * @return {boolean}
 */
export declare function isNamespace(ns: string, provider?: string): boolean;
/**
 * Checks if a given string is a valid GitHub auth token
 *
 * @param {string} token
 * @return {boolean}
 */
export declare function isGithubToken(token: string): boolean;
/**
 * @deprecated Misspelled alias of {@link isGithubToken}, kept for
 * backward compatibility.
 *
 * @param {string} token
 * @return {boolean}
 */
export declare function isGuthubToken(token: string): boolean;