/**
 * Writer.
 */
export interface StringWriter {
    /**
     * Write data.
     *
     * @param data
     *   Value.
     */
    writeString(data: string): void;
}
interface SubtleCryptoLike {
    digest(algorithm: {
        name: string;
    } | string, data: ArrayBufferView<ArrayBufferLike> | ArrayBufferLike): Promise<ArrayBuffer>;
}
/**
 * Hash a field.
 */
export type FieldHasher = (data: StringWriter) => void;
/**
 * Create a hasher for a boolean.
 *
 * @param key
 *   Key.
 * @param value
 *   Value.
 * @returns
 *   Hasher.
 */
export declare function bool(key: string, value: boolean): FieldHasher;
/**
 * Create a hasher for an unsigned 32-bit integer.
 *
 * @param key
 *   Key.
 * @param value
 *   Value.
 * @returns
 *   Hasher.
 */
export declare function uint32(key: string, value: number): FieldHasher;
/**
 * Create a hasher for a string.
 *
 * @param key
 *   Key.
 * @param value
 *   Value.
 * @returns
 *   Hasher.
 */
export declare function string(key: string, value: string): FieldHasher;
/**
 * Create a hasher for a 64-bit floating point number.
 *
 * @param key
 *   Key.
 * @param value
 *   Value.
 * @returns
 *   Hasher.
 */
export declare function float64(key: string, value: number): FieldHasher;
/**
 * Create a hasher for an array of strings.
 *
 * @param key
 *   Key.
 * @param values
 *   Values.
 * @returns
 *   Hasher.
 */
export declare function stringSliceOrdered(key: string, values: ReadonlyArray<string>): FieldHasher;
/**
 * Create a hasher.
 *
 * @param subtle
 *   Subtle crypto.
 * @returns
 *   Hasher.
 */
export declare function makeHasher(subtle: SubtleCryptoLike): (...hashers: ReadonlyArray<FieldHasher>) => Promise<string>;
export {};