anchor.diff:    int toUnsigned(int width);
   
     /// Returns the least significant [width] bits of this integer, extending the
  -  /// highest retained bit to the sign.  This is the same as truncating the value
  -  /// to fit in [width] bits using an signed 2-s complement representation.  The
  +  /// highest retained bit to the sign. This is the same as truncating the value
  +  /// to fit in [width] bits using an signed 2-s complement representation. The
     /// returned value has the same bit value in all positions higher than [width].
     ///
     /// ```dart
  
positive.code:   /// and zero-bits are shifted in as the new most significant bits.
    ///
    /// The [shiftAmount] must be non-negative.
    int operator >>>(int shiftAmount);
  
    /// Returns this integer to the power of [exponent] modulo [modulus].
  
negative.code:   ///
    /// If both operands are negative, the result is negative, otherwise
    /// the result is non-negative.
    /// ```dart
    /// print((2 & 1).toRadixString(2)); // 0010 & 0001 -> 0000
    /// print((3 & 1).toRadixString(2)); // 0011 & 0001 -> 0001
    /// print((10 & 2).toRadixString(2)); // 1010 & 0010 -> 0010
    /// ```
    int operator &(int other);
  
    /// Bit-wise or operator.
  