On 9/14/17 2:27 AM, John Maddock via Boost wrote:
Boost.Config actually uses the feature testing macros when available and when applicable (in combination with other things, i.e. an understanding of what the C++ implementation in question actually is known to support, regardless of what it advertises). Using the feature testing macros alone may not be what you want. I'd be happy to used Boost.Config - that's where I looked first. But I don't see what I need in there.
Pull requests are welcome.
Indeed, or file a feature request.
Hmmm - the problem is i'm already two interrupt levels below where I really want to be. So I was hoping for an existing fix that I didn't really have to think about. If something that starts out seeming trivial often end up sucking up a bunch of unanticipated time.
Note that historically Boost.Config has never added new macros unless there is demand from within Boost.
And while it's true that we have been laggardly in adding C++17 feature macros, so far no one has ever asked for them either... not once till now.
BTW, what I'm missing from this discussion, is exactly what C++17 features you are actually interested in?
BOOST_NO_CXX17_STD_IS_DETECTED
According to http://en.cppreference.com/w/cpp/experimental/is_detected
it's currently in