docs: function random (length) {
    // Guard
    if (length == null) {
      length = DEFAULT;
    } else if (!(typeof length === 'number' && length > 0)) {
      throw new Error('Length should be +ve Number');
    }
  
    // Fill buffer
    var bits = bitString.randomBits(6 * length);
    return baseURL.encode(bits);
  }