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On Thu, Jun 16, 2022 at 12:02:04AM +1000, Chris Angelico wrote:
On Wed, 15 Jun 2022 at 22:38, Steven D'Aprano <steve@pearwood.info> wrote:
There's no consensus that this feature is worth the added complexity, or even what the semantics are. The PEP punts on the semantics, saying that the behaviour may vary across implementations.
Excuse me? I left one or two things open-ended, where they're bad code and I'm not going to lock the language into supporting them just because the reference implementation happens to be able to, but "punts"? That's a bit much. The semantics are QUITE specific.
Under the Specification section, the PEP explicitly refers to behaviour which "may fail, may succeed", and different behaviour which is "Highly likely to give an error", and states "Using names of later arguments should not be relied upon, and while this MAY work in some Python implementations, it should be considered dubious". So, yes, the PEP *punts* on the semantics of the feature, explicitly leaving the specification implementation-dependent.
There's no consensus on the syntax, which may not matter, the Steering Council can make the final decision if necessary. But with at least four options in the PEP it would be good to narrow it down a bit. No soft keywords have been considered.
"""Choice of spelling. While this document specifies a single syntax `name=>expression`..."""
The PEP specifies *one* option.
The part of the sentence you replaced with an ellipsis says "alternate spellings are similarly plausible." The very next sentence says "Open for consideration are the following" and a couple of paragraphs later you even explicitly refer to a second proof of concept implemention. The PEP has a preferred syntax, as is its right, but it lists three alternatives still under consideration. -- Steve