export declare const getExchangeChallengeCacheKey: (token: string, challenge: string) => string;
export declare const VALID = "valid";
export declare const EXHAUSTED = "exhausted";
export declare const isExchangeChallengeValidForToken: (token: string, challenge: string) => Promise<typeof VALID | null | undefined>;
export declare const getExchangeChallengeStateForToken: (token: string, challenge: string) => Promise<typeof VALID | typeof EXHAUSTED | null | undefined>;
export declare const setValidExchangeChallengeForToken: (token: string, challenge: string) => Promise<"OK" | undefined>;
export declare const setValidExchangeChallengesForToken: (token: string, challenges: string[]) => Promise<"OK" | undefined>;
export declare const invalidateExchangeChallengeForToken: (token: string, challenge: string) => Promise<number | undefined>;
export declare const exhaustExchangeChallengeForToken: (token: string, challenge: string) => Promise<"OK" | undefined>;
//# sourceMappingURL=exchanges.d.ts.map