My original dict unpacking proposal was very short and lacked a motivating usage. Toy examples made my proposal look unnecessarily verbose and suggested obvious alternatives with easy current syntax.
Nested/recursive unpacking is much more troublesome, especially when combined with name-binding. I wrote an example to compare my proposal with current syntax.
Example usage.
Implementation.
The design of my module I'm least happy with is the name-binding. I extended a SimpleNamespace to create an Erlang-style distinction between bound and unbound names. Though the API is a bit awkward, now that the module is built, I'm less enthusiastic about introducing new syntax. Funny how that works.
I haven't yet decided how to add post-binding guards to the cases.