Re: [boost] [mpl] integral_c [type_traits] integral_constant limits

Subject: Re: [boost] [mpl] integral_c [type_traits] integral_constant limits
From: vicente.botet (vicente.botet_at_[hidden])
Date: 2010-11-16 16:15:22

----- Original Message ----- 
From: "John Maddock" <boost.regex_at_[hidden]>
To: <boost_at_[hidden]>
Sent: Monday, November 15, 2010 10:17 AM
Subject: Re: [boost] [mpl] integral_c [type_traits] integral_constant limits

> 
>>This means that with the current implementation we can not use 
>>integral_constant with the max value of the type.
>>
>>Do you think this is a bug in integral_constant?
> 
> It's nasty, but we do need MPL support in type_traits, so I don't see what 
> we can really do about this?
> 
> Can mpl be fixed not to cause numeric overflow when the value is at the 
> limit of the range?

I gues that it will be enough to overload the next and prior metafunctions on integral_c so the next and prior nestedtypes are no more nedeed, but I don't understand why the compiler is instantiating these types when not used yet. Could someone clarify if this instantiation is conforming to the standard?

Vicente