Re: [boost] [C++0x][config] Taking advantage of C++0x features as they become available

From: Beman Dawes (bdawes_at_[hidden])
Date: 2008-04-08 14:09:12

Douglas Gregor wrote:
> On Sat, 2008-04-05 at 11:49 -0400, Beman Dawes wrote:
>> Doug Gregor wrote:
>>> 	http://lists.boost.org/Archives/boost/2006/11/113534.php
>>>
>>> Boost 1.35.0 already contains some macros for C++0x features available  
>>> now, e.g., BOOST_HAS_STATIC_ASSERT (used by boost/static_assert.hpp),  
>>> BOOST_HAS_VARIADIC_TMPL, BOOST_HAS_RVALUE_REFS, and  
>>> BOOST_HAS_DECLTYPE. They have their own section of the Boost.Config  
>>> documentation ("Macros that describe C++0x Features"), and I believe  
>>> that accurately reflect the capabilities of released compilers.
>> Ah! Thanks!
>>
>> ...pause while I read that thread...
>>
>> There was some discussion of making the macros negative; 
>> BOOST_NO_STATIC_ASSERT or possibly BOOST_NO_0X_STATIC_ASSERT. That seems 
>>   both better from the maintenance standpoint, and more in line with our 
>> current practice.
>>
>> Has a final decision been made on this?
> 
> I ended up using BOOST_HAS_*, because C++0x features seemed to be such a
> long way off back then :)

Yeah, but getting closer every day:-)

> I don't mind either way. It depends on whether we C++0x as our target
> language (with workarounds for C++98) or whether C++98 is our target
> language (with extensions for C++0x). I imagine that over the next 5-10
> years, our view will shift from the latter to the former... perhaps that
> means we should just go with BOOST_NO_* now and save ourselves the
> trouble of changing our minds later.

That's my view, too! Why not plan for the future now?

John?

--Beman