Re: [boost] Heads up about future standards annexing new identifiers

Subject: Re: [boost] Heads up about future standards annexing new identifiers
From: Edward Diener (eldiener_at_[hidden])
Date: 2018-07-16 22:51:42

On 7/16/2018 6:08 PM, Marshall Clow via Boost wrote:
> As facilities get added to the standard library, they need names. When this
> happens, it restricts what other developers can and cannot do in their
> programs.
> 
> For example, one cannot do this and expect most anything in the standard
> library to work:
> 
> #define allocate(T) . new T
> 
> [ But you knew about that ].
> 
> What you may not have known about was that the standards committee has
> voted contract enforcement/checking facilities into the draft standard
> (which will probably be C++20).  This includes attributes named: 'expects'
> and 'ensures'. (all lower case)
> 
> I have checked all of boost, and with the possible exception of
> Boost.Contract, we do not have any macros with those names.
> 
> But you might want to keep your eyes open.
> 
> -- Marshall
> 
> P.S. These are not keywords - so it's perfectly fine to have member
> functions with these names. Variables, too. Probably even free functions -
> though I haven't tried that. But macros are right out ;-)+

We should not have any macros that are not all uppercase letters. All 
macro names in Boost libraries should be BOOST_SOMELIB_XXXXX... . This 
is like C++ programming 101. The fact that a number of compiler vendors 
do not follow the simple rule of having uppercase letters in macro names 
does not mean that we should follow their poor example.

> 
> P.P.S. For people who are interested, the paper is http://wg21.link/P0542