Treating the abusive unsigned syndrome

[Andrei Alexandrescu]

Sean Kelly wrote:
> Don wrote:
>>
>> Although it would be nice to have a type which was range-limited, 
>> 'uint' doesn't do it. Instead, it guarantees the number is between 0 
>> and int.max*2+1 inclusive. Allowing mixed operations encourages 
>> programmers to focus the benefit of 'the lower bound is zero!' while 
>> forgetting that there is an enormous downside ('I'm saying that this 
>> could be larger than int.max!')
> 
> This inspired me to think about where I use uint and I realized that I 
> don't.  I use size_t for size/length representations (largely because 
> sizes can theoretically be >2GB on a 32-bit system), and ubyte for 
> bit-level stuff, but that's it.
> 
> 
> Sean

For the record, I use unsigned types wherever there's a non-negative 
number involved (e.g. a count). So I'd be helped by better unsigned 
operations.

I wonder how often these super-large arrays do occur on 32-bit systems. 
I do have programs that try to allocate as large a contiguous matrix as 
possible, but never sat down and tested whether a >2GB chunk was 
allocated on the Linux cluster I work on. I'm quite annoyed by this >2GB 
issue because it's a very practical and very rare issue in a weird 
contrast with a very principled issue (modeling natural numbers).


Andrei