Re: [boost] [wave) experiences

From: Joel de Guzman (joel_at_[hidden])
Date: 2005-12-07 09:21:28

Hartmut Kaiser wrote:
>  
> Paul Mensonides wrote:
> 
> 
>>>>Supporting [extended length integers] is not a good idea.  
>>>>IMO, it is just the beginning of non-standard extensions.  
>>>>For the purpose of cross-compiling, I don't have a 
>>
>>problem with an 
>>
>>>>option to specify the width.
>>>
>>>But what about cross compiling from a 32-bit platform for a 64-bit 
>>>target?
>>>(which strikes me as a perfectly reasonable thing to do today).
>>
>>It is reasonable.  I'm not against being able to explicitly 
>>set the width with some sort of option--as long as it is 
>>explicit.  What I'm basically saying is that once the option 
>>is set, the preprocessor should do everything at exactly that 
>>width (*as if* the width was the widest supported integral 
>>type for the platform--which is required by the standard) and 
>>reject anything that requires more.  If the width isn't the 
>>width of the actual target, then the user is lying--which 
>>gives them an explicit way-out hack if absolutely necessary.
> 
> 
> That was exactly, what I had in mind.

I suggest an integer<N> class that uses built-ins when
it's detected that the compiler/platform supports N bits
and switch to an emulated fixed precision integer of N
bits when it is not available as a built-in. I also
suggest that such a class would be generally useful
in boost.

Regards,
-- 
Joel de Guzman
http://www.boost-consulting.com
http://spirit.sf.net