On Mar 21, 2019, at 16:55, Steven D'Aprano <steve@pearwood.info> wrote:

On Thu, Mar 21, 2019 at 03:10:48PM -0700, Brandt Bucher wrote:
For anyone interested in "trying it out": if you're not against cloning and
compiling CPython yourself, here is a PEP 584 C implementation I have PR'd
against master right now. I'm keeping it in sync with the draft PEP as it
changes, so subtraction performance is not overly optimized yet, but it
will show you the *exact* behavior outlined in the PEP on the dict builtin
and its subclasses. The relevant branch is called "addiction". You can
clone it from:

That's great, thank you!

For the sake of comparisons, could you support | as an alias? That will
allow people to get a feel for whether a+b or a|b looks nicer.

(For the record, the PEP isn't set in stone in regards to the choice of


Great idea. I just added this, and all tests are passing.

For reference, here’s the PR (it’s linked to the BPO, too):