anchor.diff:    Expect.equals(-128, byteArray[2]);
     byteArray[3] = 127;
     Expect.equals(127, byteArray[3]);
  -  Expect.throws(() {
  -    byteArray[1] = 1.2;
  -  });
     // This should eventually throw.
     byteArray[0] = 128;
     byteArray[4] = -129;
  +  if (check_throws) {
  +    Expect.throws(() {
  +      byteArray[1] = 1.2;
  +    });
  +  }
   }
   
   void testSetRange() {
  
positive.code: 
  }
  
  void testUnsignedByteArrayRange() {
    Uint8List byteArray;
    byteArray = new Uint8List(10);
  
  
negative.code:   byteArray[1] = 0;
    Expect.equals(0, byteArray[1]);
  
    // These should eventually throw.
    byteArray[1] = 256;
    byteArray[1] = -1;
    byteArray[2] = -129;
    if (check_throws) {
      Expect.throws(() {
        byteArray[1] = 1.2;
      });
    }
  }
  
  void testByteArrayRange(bool check_throws) {
    Int8List byteArray;
    byteArray = new Int8List(10);
    byteArray[1] = 0;
  