It looks like the std feature only serves to choose between depending on core or std, without actually depending on any of the extra features of std. If only the features of core are being used, I think this could just be a no_std crate, since std crates can depend on no_std crates just fine.
It looks like the
stdfeature only serves to choose between depending oncoreorstd, without actually depending on any of the extra features ofstd. If only the features ofcoreare being used, I think this could just be ano_stdcrate, sincestdcrates can depend onno_stdcrates just fine.