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Subject: Re: [SG10] Teleconference: June 19
From: Nelson, Clark (clark.nelson_at_[hidden])
Date: 2013-06-21 17:34:19


> | The more I look at constexpr, and the draft recommendations, the
> more I
> | think that we should be aiming for something simple for chicago.
> |
> | Therefore, I'm in favor of just
> |
> | __cplusplus_constexpr
> |
> | and setting different values to determine what level of language
> | support is being specified.
> |
> | IMHO, if this group starts coming up with 4 macros to detail
> what
> | version of constexpr is in play, it's going to be too confusing
> to use
> | in practice. What do these macros mean again? Etc.
>
> I strongly with what Benjamin said. This suggestion appears to me
> to
> be a far superior solutions to alternatives I've seen so far.

(I assume "agree with" is missing from your first sentence.)

My impression is that Benjamin's comment about "4 macros" was based on a
misunderstanding about what the document was trying to say. The four names
in that draft of the document associated with constexpr were just
alternatives that had been proposed, and from which I was expecting SG10
to select. It never occurred to me that someone might think I was proposing
to define four different macros for one feature.

Benjamin, please correct me if I'm wrong.

> Furthermore, this should not be done only for constexpr. The
> approach
> should be used as a template for all the other macros.

Benjamin did suggest that several other macros might not be needed,
including init_captures, generic_lambdas, and decltype_auto. SG10 considered
them all, and in each case reached the consensus that it would be better to
keep the specific macro than to try to do it a different way. The general
consensus was that "fewer macros is better" is not universally true.

I don't know, maybe Benjamin got tired and gave up at that point. :-/ But
Gaby, if you have any other specific suggestions of macros that you think
are not necessary, do please speak up.

Thanks,
Clark


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