Re: C++17 skeleton with move semantics and std::variant

[Hans Åberg]

> On 18 Apr 2018, at 11:19, Frank Heckenbach <address@hidden> wrote:
> 
> Hans Åberg wrote:
> 
>> Indeed. Others, may not want to patch their installations even it
>> they can, as it may cause problems for other packages. Say if one
>> writes package that uses a standard Bison installation, then it
>> would be dangerous to patch it up with an experimental one.
> 
> Not really dangerous, as my C++17 patch only adds new files. (My other
> patches change existing files, but they are rather small, and just
> bugfixes.)

It is your package, so you do with what you want.

>>>> But if someone uses their of variants type, would that require C++11?
>>> 
>>> Yes, the skeleton uses move semantics (i.e. rvalue references), so
>>> C++11 is the minimum. (Not entirely sure if I accidentally used some
>>> C++14 feature, as that's what I tested with besides C++17, but if
>>> so, it may be rather easy to avoid.)
>> 
>> Would it in principle possible to use ones own variants that does
>> not require C++11 and put the C++11 code within preprocessor
>> directives so that it works for earlier C++ versions? - I am not
>> sure there would be any use for this, just wondering.
> 
> Not (easily) with my patch, as it uses move semantics throughout.
> For this use case, I think it would be easier to start with the
> C++03 skeleton and change the variant implementation there.

OK.