[PPL-devel] Re: Problems with std::numeric_limits

[Roberto Bagnara]

Paolo Carlini wrote:
>> Is that default implementation mandated by the standard?
>> If so, well... fine.
> 
> I think it is: 18.2.1.1/2. But I don't know the rationale...
> 
>>   But if it is not mandated then I think it makes
>> much sense to remove it as it seems a perfect recipe for disaster.
>>
>> Another issue is: shouldn't, e.g., std::numeric_limits<int> and
>> std::numeric_limits<const int> be completely equivalent?
> 
> I tend to agree, but I'm not sure would be conforming: see 18.2.1/2 and
> /4, in particular, which says: "Non fundamental standard types, such as
> complex<T>, shall not have specializations".
> 
> I don't think a cv-qualified fundamental type qualifies as a fundamental
> type. According to 3.9.3, "A type mentioned in 3.9.1 and 3.9.2 is a
> cv-unqualified type", where 3.9.1 is the section named "Fundamental
> types" and describing all those types.

Dear Paolo,

I think your reading of the standard is completely correct.
It seems that, in order to play safe, one really has to use
the is_specialized member.
Many thanks,

     Roberto

-- 
Prof. Roberto Bagnara
Computer Science Group
Department of Mathematics, University of Parma, Italy
http://www.cs.unipr.it/~bagnara/
mailto:bagnara at cs.unipr.it