Support -fno-exceptions build

[mizvekov]

Would be nice if this library, or at least some subset of it, could be built using C++-without-exceptions dialect.

[ned14]

Chances are low, the code base was designed to be used from C++ exceptions disabled code, but to compile it would require C++ exceptions as those would be used internally.

It probably wouldn't be a massive task to make the source C++ exceptions disabled friendly, just time and effort.

[ethindp]

I'm a bit confused as to why. Is this library supposed to conform to P1031 semantics? I.e., isn't it supposed to be a reference implementation of that paper? I'd think it'd be best if it's (at least theoretically) trivial to switch to the stdlib version if it does get adopted and standardized. Which means consistent behavior. Plus, all functions already return a outcome anyway (or most of them do). Just my $0.02.

[ned14]

I shall be quitting WG21 next summer, so all my proposals including the one to standardise this library have been axed. I think seven years is enough for WG21 to standardise something, if they can't do it within seven years, it's time for me to move on to places more productive with my time.

This library will be maintained, but I don't expect to add much new to it going forth as I will be deprioritising C++ work from 2025 onwards. All that said, donations of a noexcept capable build I'm sure the userbase would welcome.