anchor.diff:  
   		while (true) {
   			if (this.readBit()) {
  -				this.position--;
  +				this._position--;
   				break;
   			} else {
   				bits++;
  
positive.code: 		int bytepos = (position / 8.0).floor();
  		int bitpos = position % 8;
  
  		int byte = bytes.getUint8(bytepos);
  
  		return byte & (1 << bitpos) > 0;
  	}
  
  	/// Reads the next bit from the buffer.
  	bool readBit() {
  		bool val = this._read(this.position);
  		position++;
  		return val;
  	}
  
  
negative.code: 	/// Bit position within the current working byte.
  	int _position = 0;
  
  	/// Creates a new ByteBuilder with an empty buffer.
  	ByteBuilder();
  
  	/// Appends a single bit to the buffer.
  