On 2020-05-06 12:48 p.m., Christopher Barker wrote:
On Tue, May 5, 2020 at 5:43 PM Steven D'Aprano <steve@pearwood.info <mailto:steve@pearwood.info>> wrote:
Christopher's quoting is kinda messed up and I can't be bothered fixing it, sorry, so you'll just have to guess who said what :-)
Ideally, we are evaluating ideas independently of who expressed them, so I'll pretend I did that on purpose :-)
First: really people, it's all been said. I think we all (and I DO include myself in that) have fallen into the trap that "if folks don't agree with me, I must not have explained myself well enough" -- but in this case, we actually do disagree. And not really on the facts, just on the relative importance.
But since, I apparently did not explain myself well enough in this case:
no -- but we could (and I think should) have a ternary flag, so that
> zip_longest becomes unnecessary. And we'd never get to eight combinations: > you can't have longest and shortest behavior at the same time!
A ternary flag of strict = True, False or what?
Come on:
ternary: having three elements, parts, or divisions (https://www.merriam-webster.com/dictionary/ternary)
did you really not know that? (and "flag" does not always mean "boolean flag", even thoughit often does (https://techterms.com/definition/flag) )
(by the way, I'm posting those references because I looked them up to make sure I wasn't using terms incorrectly)
This has been proposed multiple times on this list:
a flag that takes three possible values: "shortest" | "longest" | "equal" (defaulting to shortest of course). Name to be bikeshed later :-) (and enum vs string also to be bikeshed later)
how about "length"? length=True # longest length=False # shortest (default) length=None # equal (altho I still think the "YAGNI function" system would be better >.>)
This demonstrates why the "constant flag" is so often an antipattern. It doesn't scale past two behaviours. Or you end up with a series of flags:
zip(*iterators, strict=False, longest=False, fillvalue=None)
I don't think anyone proposed an API like that -- yes, that would be horrid.
There are all sorts of reasons why a ternary flag would not be good, but I do think it should be mentioned in the PEP, even if only as a rejected idea.
But I still like it, 'cause the "flag for two behaviors and another function for the third" seem sliek the worse of all options.
-CHB
-- Christopher Barker, PhD
Python Language Consulting - Teaching - Scientific Software Development - Desktop GUI and Web Development - wxPython, numpy, scipy, Cython
_______________________________________________ Python-ideas mailing list -- python-ideas@python.org To unsubscribe send an email to python-ideas-leave@python.org https://mail.python.org/mailman3/lists/python-ideas.python.org/ Message archived at https://mail.python.org/archives/list/python-ideas@python.org/message/LSKG4X... Code of Conduct: http://python.org/psf/codeofconduct/