GeezerVison

I would not recommend it for now. You can use it on your own risk. optparse may need more work, but it works as expected. I would recommend it for beginners, which cannot distinguish their own errors from peculiarities of the library.

For this PR, I'd like to stick with the status quo as far as recommendations go (that is, only taking the step back from "argparse is the only non-deprecated argument processing option in the standard library").

Taking the extra step to saying "argparse is not recommended over optparse anymore, even for end user applications" would then be a separate follow up question.

Indeed. Keep the argparse recommendation. We're not going to dis-recommend the most widely used Python argument parsing library in the world (that causes churn and angst from users). Nor are we going to be adding yet another one to the stdlib in the future. argparse supports most users quite well, "warts" and all, with plenty of popular third party options for yet other behaviors beyond our stdlib options.

@serhiy-storchaka ^^^ is the main reason I don't think we should walk back the default argparse recommendation. Many (probably even most) Python devs would consider argparse to be in the right for these 3 examples, and getopt/optparse the ones doing something dubious (even if what they're doing is the common Unix convention).

The discrepancies are valid reasons for reverting the soft deprecation (optparse can genuinely be used to define command line behaviours that argparse doesn't support), but it will take less arguable examples than these ones to make the case that optparse should be preferred over argparse in general.

It would be better to write about these peculiarities in the argparse module documentation. The getopt module documentation is not the place where users will search information about the argparse module.

agreed. I like that we're giving a list of differences in behavior, but I think it makes more sense to put this in a common section :ref:'d from all three of our command line parsing module docs. I don't expect anyone reading argparse (most likely) or optparse (likely) docs to find this in the getopt docs (presumed least likely to be read).

I've moved this to a new "Choosing an argument parsing library" section at the start of the optparse docs. getopt still has the example code, but refers to that new section to explain the differences.

Similar, I made the note at the start of the argparse docs shorter, and added a link to this new section.