Disallow locally-generated types from escaping their function

[msullivan]

We should ban locally generated types (such as NamedTuples declared inside of functions and types generated by uses of callable) from escaping the function where they are created.

It isn't really a good idea to do in the first place and it has difficult interactions with both coarse and finen-grained incremental.

[gvanrossum]

These may also interact poorly with 'from __future__ import annotations', so perhaps that's another reason to ban them?

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On Tue, Mar 6, 2018, 17:22 Michael J. Sullivan ***@***.***> wrote: We should ban locally generated types (such as NamedTuples declared inside of functions and types generated by uses of callable) from escaping the function where they are created. It isn't really a good idea to do in the first place and it has difficult interactions with both coarse and finen-grained incremental. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#4690>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ACwrMqOxjRRWgskkYz9zMHFieJA92lP9ks5tbzZDgaJpZM4SftXO> .