Re: [boost] Macro fo rBOOST_NO_NUMERIC_LIMITS_MAX_DIGITS10 or useBOOST_NO_NUMERIC_LIMITS_LOWEST

Subject: Re: [boost] Macro fo rBOOST_NO_NUMERIC_LIMITS_MAX_DIGITS10 or useBOOST_NO_NUMERIC_LIMITS_LOWEST
From: Marshall Clow (mclow.lists_at_[hidden])
Date: 2012-07-12 10:01:44

On Jul 11, 2012, at 10:25 AM, Paul A. Bristow wrote:
>> On Jul 11, 2012, at 9:20 AM, John Maddock wrote:
>> 
>>>> I have recently used BOOST_NO_NUMERIC_LIMITS_LOWEST to act as a proxy
>>>> for support of
>>>> numeric_limits<T>:: max_digits10 (as correctly suggested by John Maddock).
>>>> 
>>>> Do we need yet another  new macro for this, say
>>>> 
>>>> BOOST_NO_NUMERIC_LIMITS_MAX_DIGITS10
>>>> 
>>>> or continue to use  BOOST_NO_NUMERIC_LIMITS_LOWEST as a proxy.
>>>> 
>>>> I think the latter will suffice (despite its unfortunate name for this task).
>>>> 
>>>> But I think an addition to the configuration macro reference docs would be useful.
>>> 
>>> Actually, this is one C++11 macro that Marshall missed for renaming.
>> 
>> I didn't touch that macro, because I didn't think it was a C++11 one.
>> 
>> Looking back at the discussion from last month, I see a proposal to add a new macro named
>> BOOST_NO_NUMERIC_LIMITS_MAX_DIGITS10, and when John asked for a patch, Paul contributed some
>> bits, but not a complete patch; and no one else did.
>> 
>>> Maybe if we asked him nicely ;-)  he would volunteer to rename this one to
>> BOOST_NO_CXX11_NUMERIC_LIMITS?
>> 
>> I don't think that this is a rename job.
>> If I've misread the discussion (or misunderstood the situation), please let me know.
> 
> BOOST_NO_NUMERIC_LIMITS_LOWEST works as a proxy for BOOST_NO_NUMERIC_LIMITS_MAX_DIGITS10
> 
> but there are other new things added at CX11 too, so really BOOST_NO_NUMERIC_LIMITS_LOWEST turns out
> to be a bad name.
> 
> John suggests renaming BOOST_NO_NUMERIC_LIMITS_LOWEST  to BOOST_NO_CXX11_NUMERIC_LIMITS  (and I
> think this is a god idea to avoid adding the already long list of macros).
> 
> This macro BOOST_NO_CXX11_NUMERIC_LIMITS  will then deal with the need for
> BOOST_NO_NUMERIC_LIMITS_MAX_DIGITS10, BOOST_NO_NUMERIC_LIMITS_LOWEST  *and* all the other items
> added to numeric_limits at Cxx11.
> 
> Hope this is clearer now.
> 
> Paul
> 
> PS And if this is done, we will need to update the docs.  I will do this if you wish.

Ok, it's done (revision 79452).

The new macro is named BOOST_NO_CXX11_NUMERIC_LIMITS, replacing BOOST_NO_NUMERIC_LIMITS_LOWEST.
The old macro is still around, but set to the value of the new macro, and is listed in the "deprecated macros" section of the docs.

Paul - please feel free to update the docs to explain how this works (and update your code to use the new macro, natch).

-- Marshall

Marshall Clow     Idio Software   <mailto:mclow.lists_at_[hidden]>

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