Chris Angelico writes: > On Sun, Dec 5, 2021 at 3:08 PM Stephen J. Turnbull > <stephenjturnb...@gmail.com> wrote:
> > This one is Worth Doing Right the first time, I think. And IMO David > > Mertz is right: doing it right means a more general deferred-evaluation > > object (not to be confused with Deferreds that need to be queried > > about their value). > > If you think that deferred evaluation objects are the right way to do > it, then write up a proposal to compete with PEP 671. That's not your call, I'm afraid. "Keep the status quo" is always a viable option, regardless of other options. And other things equal, it's the preferred option. > In my opinion, it is a completely independent idea, You're welcome to your opinion, of course. But if you want to claim that's a reason for implementing your proposal, you need to support it. You also need to explain why the additional potential complexity of a third kind of default argument (evaluated at definition, evaluated during call, evaluated when referenced) isn't a big problem. > which is not a complete replacement for late-bound defaults; Why not? If we have such objects, we could simply specify that in the case where such an object is specified as a function parameter default, it is evaluated in the same environment as your late-bound defaults. So we can have your schsemantics if that's what we want. On the other hand, it might turn out that 90% of the time, it doesn't matter if it's evaluated as part of the calling process, 9% of the time the natural place to evaluate it is at the point of first use, and 1% of the time it should be evaluated before the function body proper is entered. In that case the late-bound default would be of some utility, but is it worth it? David's "infinitesimal utility" argument seems likely to apply. What else would such a deferred-evaluation object be unable to do that your late-bound default can do? > we could continue to have neither. That's where I am. More than any of these issues, the lack of a well- defined, properly introspectable object bothers me. In 2021, we should provide that. _______________________________________________ Python-ideas mailing list -- python-ideas@python.org To unsubscribe send an email to python-ideas-le...@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/5KA2FKOFWXAETELXR3SHOGB7657TTWPJ/ Code of Conduct: http://python.org/psf/codeofconduct/
