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bpo-36077: Update handling of defaulted fields by EpicWink · Pull Request #17322 · python/cpython

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@EpicWink

When a non-defaulted dataclass field follows a defaulted field, the behaviour has changed from raising a TypeError to making all arguments in __init__ following the defaulted field keyword-only.

I'm not sold on the prettiness of the versionchanged area in the docs change: please comment.

https://bugs.python.org/issue36077

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When a non-defaulted dataclass field follows a defaulted field, the
behaviour has changed from raising a `TypeError` to making all arguments
in `__init__` following the defaulted field keyword-only.

@jdlourenco

@EpicWink

@ericvsmith

We don't typically update PEPs when new features are added.

@EpicWink

Other way around: this pull-request is in direct contradiction with the PEP (it says that non-defaulted fields following defaulted fields cause a TypeError)

@ericvsmith

It doesn't matter: PEPs are not meant to describe current behavior.

@EpicWink

@NeilGirdhar

This is so useful! Thanks for the patch.

@randallpittman

Thank you for the patch. Any way to know if this will get into 3.10?

@EpicWink

@ericvsmith

@EpicWink

This has been superseded by the more explicit solution to be included in Python 3.10 #24909

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