Re: [Config] Swappable/Movable std::streambuf requirement

From: Alexander Grund (alexander.grund_at_[hidden])
Date: 2020-05-18 09:05:53

>> C++11 has  `std::basic_streambuf<char>::swap` and move operators for that defined.
>>
>> However there are stdlibs which don't support that. clang 5.0 on travis e.g. fails due to that.
>>
>>
>> Is there already something in Boost.Config dealing with that case which I can `requires` on to skip the build for that case?
>> Most of the checks I've seen in Boost.Config are using the C++ feature test macros but for this there is none.
>>
>>
>> If it doesn't exist: Would this be something to be added to Boost.Config? Or my local build files?
> You can write a snippet that compiles or breaks and make your test conditional on this. Look for “boost_multi_index_key_supported” in
>
> https://github.com/boostorg/multi_index/blob/develop/test/Jamfile.v2

Done:
https://github.com/boostorg/nowide/pull/97/files?file-filters%5B%5D=.v2#diff-f7ff2f2ced58a7096ff8d20a8b12938bR17-R18 
and 
https://github.com/boostorg/nowide/pull/97/files?file-filters%5B%5D=.v2#diff-e97299ad55a4013dc19889043aa464a5R14-R15

Are there any requirements on the name? I used `cxx11_moveable_fstreams` 
to by in line with the BoostConfig checks as this is very similar.

Alex