For the backwards compatibility section, it would be good to analyze how the change impacts error reporting.

(1) is the suggested syntax currently a 'common error' that will become harder to detect once it's not a syntax error?

(2) would adding this syntax impact the parser's ability to provide friendly error messages?  (Pablo did a lot of work on error messages for 3.10, so check a current python version).

I'm not saying I'm seeing an issue - just that these points need to be thought through and perhaps mentioned in the PEP.

On Tuesday, October 26, 2021, 02:55:09 AM GMT+1, Erik Demaine <> wrote:

On Sat, 16 Oct 2021, Erik Demaine wrote:

> Assuming the support remains relatively unanimous for [*...], {*...}, and
> {**...} (thanks for all the quick replies!), I'll put together a PEP.

As promised, I put together a pre-PEP (together with my friend and coteacher
Adam Hartz, not currently subscribed, but I'll keep him aprised):

For this to become an actual PEP, it needs a sponsor.  If a core developer
would be willing to be the sponsor for this, please let me know.  (This is my
first PEP, so if I'm going about this the wrong way, also let me know.)

Meanwhile, I'd welcome any comments!  In writing things up, I became convinced
that generators should be supported, but arguments should not be supported;
see the document for details why.

Erik Demaine  |  |
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