Deriving from `Conditionally{Constructible,Assignable}` publicly rather than
privately is more natural after all. I was mistaken before.
They define public members. Special member functions have peculiar defaulting
rules so the derived class has them public either way, but the principle stands.
PiperOrigin-RevId: 889836994
Riegeli/records is a file format for storing a sequence of string records, typically serialized protocol buffers. It supports dense compression, fast decoding, seeking, detection and optional skipping of data corruption, filtering of proto message fields for even faster decoding, and parallel encoding.
See documentation.
Riegeli file format will only change in a backward compatible way (i.e. future readers will understand current files, but current readers might not understand files using future features).
Riegeli C++ API might change in incompatible ways.