Nested Mapping

[Paul Rubin]

Raymond Hettinger <python at rcn.com> writes:
> I would appreciate any feedback on the API and on how well it fits
> with various use cases that you've found in the wild.

What I really want is a Haskell-like persistent (i.e. purely functional)
dictionary implemented as an AVL tree or something like that.  It means
the "child" can just be a forked version of the parent, that shares most
of the same nodes.  I think that handles most of the obvious uses of the
nested mapping proposal.

Hedgehog Lisp has AVL-based persistent dictionaries implemented in C,
that I've been thinking of trying to port to the Python C API sometime.