symmetric signed types

[Dominikus Dittes Scherkl]

On Friday, 24 January 2014 at 11:43:08 UTC, eles wrote:
> On Friday, 24 January 2014 at 10:40:46 UTC, Dominikus Dittes 
> Scherkl wrote:
>> On Thursday, 23 January 2014 at 20:35:56 UTC, Andrei 
>> Alexandrescu wrote:
>
>> int a = 2_000_000_000;
>> int b = a + a;
>>
>> should not generate weird stuff like -294_967_296 (which it
>
> Long discussion about signed/unsigned integer overflows...

But that is a HUGE source of errors, even in really carefully 
developed software in safety critical systems!
I think it is well worth a thought to have a safe type in the 
language, even if we buy it with a small performance tradeoff. 
Especially for the "automatic" type where the programmer has not 
spend much time in carefully choosing the types to be used (e.g. 
the code above, even with "auto" instead of "int").

--> If I write code fast, without thinking about subtleties (like 
e.g. the return type of main() in "hello world") I expect the 
compiler to do something sensible (ok, I doesn't expect if from 
C, but we're talking about a better language, do we?) and I don't 
expect highest performance.

So I would prefer to have save signed types as default and maybe 
new types "sbyte", "sshort", "sint" etc if I need the last bit of 
performance, but without automatic conversion to those unsave 
types.
Using fast signed types with all the over/underflow and other 
unsafe stuff is like manual memory management and pointers 
instead of GC and slices - useful to have in case you really need 
them, but not the default.