/**
 * Provides an implementation of HMAC (Hash-based Message Authentication Code).
 *
 * https://en.wikipedia.org/wiki/HMAC
 *
 * @module
 *
 * @example
 *
 * ```ts
 * import { vec } from '../../types/bit_vec/module.f.ts'
 * import { msbUtf8 } from '../../text/module.f.ts'
 * import { sha256 } from '../sha2/module.f.ts'
 *
 * const r = hmac(sha256)(msbUtf8('key'))(msbUtf8('The quick brown fox jumps over the lazy dog'))
 * if (r !== vec(256n)(0xf7bc83f430538424b13298e6aa6fb143ef4d59a14946175997479dbc2d1a3cd8n)) { throw r }
 * ```
 */
import { type Vec } from '../../types/bit_vec/module.f.ts';
import { type Sha2 } from '../sha2/module.f.ts';
/**
 * Generates an HMAC (Hash-based Message Authentication Code) using the specified SHA-2 hash function.
 *
 * @param sha2 - The SHA-2 hash function implementation to use.
 * @returns - A function that takes a key and returns another function
 * that takes a message and computes the HMAC.
 */
export declare const hmac: (sha2: Sha2) => (k: Vec) => (m: Vec) => Vec;