Naive idiom questions

[Paul Rubin]

Terran Melconian <te_rem_ra_ove_an_forspam at consistent.org> writes:
> I guess for complete symmetry, there should then be frozendicts as well,
> although I don't envision a lot of use for them at the moment.

There should definitely be frozendicts and I've been wanting to write
an implementation.  The main thing about them is if they are
implemented as tree structures instead of hashes, you can efficiently
make differing versions of them that share structure, basically giving
you version rollback for free.  And since they are immutable, you can
share them between threads without needing to mess with locks.  I've
posted about this a couple times in the past.