Problem with object understanding and datatypes

[Ali Çehreli]

On 05/24/2013 01:19 PM, Namal wrote:

 >              if(rhs.max - rhs._value < _value)

I had a compilation error so I had to change that line to the following:

             if(T.max - rhs._value < _value){

 >      assert(subyte(128) - subyte(129) == subyte(0));
 > }
 >
 > But the last test does not pass.

255 - 129 is less than 128 so the result is T.max, which is 255, which 
is not equal to 0.

 > Why does the minus operation is treated in signed datatype, while + is
 > unsigned?

I don't think that is happening at all but the rules can get pretty 
confusing. See "Integer Promotions" and "Usual Arithmetic Conversions" 
should be known in general: :)

   http://dlang.org/type.html

Ali