anchor.diff:    Future<List<T>> read(int size) {
       // If we have enough data to consume and there are no other readers, then
       // we can return immediately.
  -    if (limit > 0 && size > limit) {
  +    if (limitted && size > limit) {
         throw new ArgumentError("Cannot read $size with limit $limit");
       }
   
  
positive.code: 
    final int limit;
  
    /**
     * Create a stream buffer with optional, soft [limit] to the amount of data
     * the buffer will hold before pausing the underlying straem. A limit of 0
  
negative.code:     _sub = stream.listen((items) {
        _chunks.add(items);
        _counter += items.length;
        if (limitted && _counter >= limit) {
          _sub.pause();
        }
  
  