GH-87358: Add clarification about nargs and default argparse behaviour #124094
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savannahostrowski
added
docs
Doc/library/argparse.rst
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| For other nargs_ values, the argument is treated as a required argument and | ||
| the default_ value is ignored. |
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This looks misleading, because it is not clear that this only relates to positional arguments.
On other hand, default is also has no effect for required optional arguments.
We could say that the default value is ignored for required arguments (there may be a reference to the required attribute).
savannahostrowski
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savannahostrowski
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For future reference: Avoid rebase and force pushing as it causes codeowners assignment for all of the other changes rebased in. Just merge main in instead. We all do this from time to time. (Even at work!) It's a GitHub git internals UX flaw. 😅 |
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Yeah, oof, that's my bad! Apologies for the noise, folks 😅. |
serhiy-storchaka
added
needs backport to 3.12
| @@ -1122,6 +1122,9 @@ is used when no command-line argument was present:: | |||
| >>> parser.parse_args([]) | |||
| Namespace(foo=42) | |||
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| For required_ arguments, the ``default`` value is ignored. For example, this | |||
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Aside: we have a (somewhat unusual) convention of using italics for arguments instead of literal code formatting:
https://devguide.python.org/documentation/markup/
But I see we're using literals elsewhere in this file so it's best to be consistent.
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Thanks @savannahostrowski for the PR, and @hugovk for merging it 🌮🎉.. I'm working now to backport this PR to: 3.12, 3.13. |
…haviour (pythonGH-124094) (cherry picked from commit 20ccda0) Co-authored-by: Savannah Ostrowski <savannahostrowski@gmail.com>
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GH-124440 is a backport of this pull request to the 3.13 branch. |
…haviour (pythonGH-124094) (cherry picked from commit 20ccda0) Co-authored-by: Savannah Ostrowski <savannahostrowski@gmail.com>
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GH-124441 is a backport of this pull request to the 3.12 branch. |
After reading through the issue's comments, it seems like all that's needed here is additional clarification in the argparse docs about how
nargsanddefaultinteract.📚 Documentation preview 📚: https://cpython-previews--124094.org.readthedocs.build/