Message 394738 - Python tracker

➜

This issue tracker has been migrated to GitHub, and is currently read-only.
For more information, see the GitHub FAQs in the Python's Developer Guide.

Author	gvanrossum
Recipients	Nils Kattenbeck, gvanrossum, keithblaha, levkivskyi
Date	2021-05-29.21:09:42
SpamBayes Score	-1.0
Marked as misclassified	Yes
Message-id	<[email protected]>
In-reply-to

Content
> What is/was the initial reason to not preserve the MRO for a TypedDict? Hm, I can't say for sure. I believe it had something to do with TypedDict instances being instances of dict at runtime, but I can't actually reconstruct the reason. Maybe it's written up in PEP 589, but I suspect not (I skimmed and couldn't find it). If you ask on typing-sig maybe David Foster (who contributed the initial idea and implementation) remembers.

> What is/was the initial reason to not preserve the MRO for a TypedDict?

Hm, I can't say for sure. I believe it had something to do with TypedDict instances being instances of dict at runtime, but I can't actually reconstruct the reason. Maybe it's written up in PEP 589, but I suspect not (I skimmed and couldn't find it). If you ask on typing-sig maybe David Foster (who contributed the initial idea and implementation) remembers.

History
Date	User	Action	Args
2021-05-29 21:09:42	gvanrossum	set	recipients: + gvanrossum, levkivskyi, Nils Kattenbeck, keithblaha
2021-05-29 21:09:42	gvanrossum	set	messageid: <[email protected]>
2021-05-29 21:09:42	gvanrossum	link	issue41249 messages
2021-05-29 21:09:42	gvanrossum	create