On 15/11/20 10:48 pm, Paul Sokolovsky wrote:
> [from PEP 635]
Pattern matching is complimentary to the object-oriented paradigm.

BTW, there seems to be a typo here -- I think it's
meant to be "complementary".

please explain why you chose to proceed anyway (and apply workarounds),
instead of first introducing the concept of constants to the language.
(Given that amount of work to implement pattern matching is certainly
an order of magnitude larger than to introduce constants)."

That's not certain at all, and moreover it's not just a matter of
work, it's a language design issue that would require its own
extensive investigation and debate. Members of the intended audience
(people very familiar with Python and its technicalities) can be
expected to understand this, so the PEP doesn't need to spell it out.

How to support multiple variable scopes in one stack frame is not a
rocket science at all. One just need to remember how C did that

We can't just do it "like C does" because C requires variables to
be declared and Python doesn't.

The only reasons for not implementing the same solution in Python would
be intertia of thought and "but it's not done anywhere else in

No, other reasons include that it would require making unrelated
language changes that open various other wormcans.

nobody del'eted local variables behind users' backs
either, before somebody started to do that for exception clause

There was a good reason for that having to do with reference cycles.
Nobody liked it much, but we didn't really have a choice. There is
no such pressing need for special scope rules in match statements.

Python-Dev mailing list -- python-dev@python.org
To unsubscribe send an email to python-dev-le...@python.org
Message archived at 
Code of Conduct: http://python.org/psf/codeofconduct/

Reply via email to