export type ConstantTimeApiKeyEntry<T> = {
    readonly digest: Uint8Array;
    readonly value: T;
};
export type ConstantTimeApiKeyMatcher<T> = {
    readonly entries: ReadonlyArray<ConstantTimeApiKeyEntry<T>>;
    matches(presentedKey: string): boolean;
};
export declare function createConstantTimeApiKeyEntry<T>(key: string, value: T): ConstantTimeApiKeyEntry<T>;
export declare function createConstantTimeApiKeyMatcher(keys: ReadonlyArray<string>): ConstantTimeApiKeyMatcher<undefined>;
export declare function createConstantTimeApiKeyMatcher<T>(keys: ReadonlyArray<{
    readonly key: string;
    readonly value: T;
}>): ConstantTimeApiKeyMatcher<T>;
export declare function findConstantTimeApiKeyMatch<T>(presentedKey: string, entries: ReadonlyArray<ConstantTimeApiKeyEntry<T>>): ConstantTimeApiKeyEntry<T> | null;