/**
 * @name u8aFixLength
 * @summary Shifts a Uint8Array to a specific bitLength
 * @description
 * Returns a uint8Array with the specified number of bits contained in the return value. (If bitLength is -1, length checking is not done). Values with more bits are trimmed to the specified length.
 * @example
 * <BR>
 *
 * ```javascript
 * import { u8aFixLength } from '@pezkuwi/util';
 *
 * u8aFixLength('0x12') // => 0x12
 * u8aFixLength('0x12', 16) // => 0x0012
 * u8aFixLength('0x1234', 8) // => 0x12
 * ```
 */
export declare function u8aFixLength(value: Uint8Array, bitLength?: number, atStart?: boolean): Uint8Array;
