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Subject: Re: [boost] [config] Macro for null pointer
From: Jeffrey Lee Hellrung, Jr. (jeffrey.hellrung_at_[hidden])
Date: 2012-12-07 17:07:42

On Fri, Dec 7, 2012 at 12:14 PM, Daniel Russel <drussel_at_[hidden]> wrote:

> > Well, I think some individuals here (I'd put myself in that camp) are
> > opposed to injecting anything into the global namespace if it can be
> > helped, and here it certainly can be helped. So if we add a nullptr
> > emulation in Boost, it's going to have to be paired with a using macro, a
> > different name (i.e., boost::nullptr_), or both. If no one will use this
> > utility given the latter imperfections, I'm fine with just dropping the
> > proposal altogether and everyone can go back to using NULL or C++11.
> Just to put in my vote for not putting anything in the global namespace
> but providing a "BOOST_USING_NULLPTR" macro. We keep our nullptr emulation
> in our library namespace too and would gladly switch to a boost one.

Good to know.

For use cases, distributed libraries that have a namespace can just use the
> macro to pull nullptr into their namespace and non-distributed libraries or
> executables without namespace can safely use the macro to pull it into the
> global namespace (since they know their environment). This is, in general,
> one line of code for the whole project if you stick it in the config
> header. The only problematic case are distributed C++ libraries that don't
> have a namespace. But I'm fine making those do more awkward things as it is
> bad practice and, I think, not that common any more.
> --Daniel

That's a good point...

- Jeff

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