export declare const PKCE_LS_PREFIX = "pkce";
export declare const PKCE_LS_STATE = "pkce_state";
export declare const PKCE_LS_VERIFIER = "pkce_verifier";
/** Create a securely random string */
export declare const secureRandomString: (length?: number) => string;
/** Create a PKCE (proof key for code exchange) challenge from a given securely randomly-generated string (verifier). */
export declare const pkceChallengeFromVerifier: (v: string) => Promise<string>;