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A comment on Python argparse has a limitation on argument groups that makes me sad.

Re:Python argparse has a limitation on argument groups that ... by mjevans on Saturday June 14, 2025 @03:33PM (#44278301)
Is there a standard python library that does annotate if an argument is user provided or instead (just) the default value?

This is extremely important for configuration priority. Program defaults (generally) should be the lowest priority level. Superseded by configuration files. Superseded by command-line arguments. Finally replaced by configuration changes during runtime. Notably each is (in theory) specified in a more specific context as well as more recently.

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Re:Python argparse has a limitation on argument groups that ... by dodslaser on Saturday June 14, 2025 @04:15PM (#44278526)
This can be done using click.
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Re:Python argparse has a limitation on argument groups that ... by ErikBjare on Saturday June 14, 2025 @04:37PM (#44278663)
Not with multiple=True, since it then always returns an empty list and never None, even if the default is None.
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Re:Python argparse has a limitation on argument groups that ... by dodslaser on Tuesday June 17, 2025 @06:52AM (#44297622)
Yes it can. click.Context provides a get_parameter_source method that should help with that.
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Re:Python argparse has a limitation on argument groups that ... by ErikBjare on Thursday June 19, 2025 @04:10PM (#44322117)
[delayed]
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Re:Python argparse has a limitation on argument groups that ... by Neywiny on Saturday June 14, 2025 @04:04PM (#44278481)
I think this is doable but as an X vs Y problem. You can either not have a default and check if it's in the namespace later, or make the default value be the previously highest priority value as a run-time defined default. Do either of those work?
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Re:Python argparse has a limitation on argument groups that ... by mjevans on Saturday June 14, 2025 @04:53PM (#44278759)
It would be nice if --help reports the (program) default as the default value for an option. A different option might dump a fully evaluated configuration. While a third might exit without doing anything.
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Re:Python argparse has a limitation on argument groups that ... by Elixir6419 on Thursday June 19, 2025 @07:13AM (#44317522)
if you pass formatter_class=argparse.ArgumentDefaultsHelpFormatter) you will get exactly that.

shameless copy from https://stackoverflow.com/questions/12151306/argparse-way-to...

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