In clang-format 10, SpaceInEmptyBlock is introduced, and defaults to
true .. which is different from the earlier formatting versions did.
For now, refuse clang-format 10, and search specifically also for
clang-format-9.0.1 because that's what I have on my laptop.
At some point, switch in the config option and then require
clang-format 10 or later (because earlier versions refuse to
run with an unknown config option)
- astyle can do some things that clang-format doesn't (e.g.
adding brackets; you need clang-tidy for that),
- clang-format does a much nicer job with lambdas and certain
other constructions,
- allow passing in directories at a time for formatting.
