anchor.diff:    /// http://tools.ietf.org/html/rfc4122.html#section-4.2.2
     String v1({Map<String, dynamic>? options}) {
       var i = 0;
  -    var buf = List<int>.filled(16, 0);
  +    var buf = Uint8List(16);
       options = (options != null) ? options : {};
   
       var clockSeq =
  
positive.code:     var i = offset, ii = 0;
  
      // Create a 16 item buffer if one hasn't been provided.
      buffer = (buffer != null) ? buffer : List<int>.filled(16, 0);
  
      // Convert to lowercase and replace all hex with bytes then
      // string.replaceAll() does a lot of work that I don't need, and a manual
  
negative.code: library uuid;
  
  import 'dart:typed_data';
  
  import 'uuid_util.dart';
  import 'package:crypto/crypto.dart' as crypto;
  