core.checkedint

[Walter Bright via Digitalmars-d]

On 6/24/2016 6:42 PM, Andrei Alexandrescu wrote:
> With your suggestion, this would also be an overflow:
>
> long x = -1;
> auto y = array.length + x;
>
> I would be hard pressed to acknowledge that as an overflow that needs to be
> dynamically signaled. And the beauty of two's complement is that indeed it just
> works.

That's a seductive test case. But I worry that mixed signed/unsigned arithmetic 
is not so simple.

What about:

     x + array.length
     commutativity in general
     associativity

Does this become a morass of special cases?