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Author JelleZijlstra
Recipients JelleZijlstra, domdfcoding, gvanrossum, joperez, kj, levkivskyi, uriyyo
Date 2021-07-19.18:47:24
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> Using `from __future__ import annotations` it should work

Not in type aliases or generic bases. (And if Larry's co_annotations PEP is accepted, it would break in normal annotations too.) I'd prefer to get rid of this sort of subtle difference where the obvious way to write a type only works in some contexts, though I realize that's not possible in all cases.

That means I think we should move forward with making NewTypes into instances with __call__ instead of functions, though according to my benchmarks in the typing issue that will incur a small performance penalty.
Date User Action Args
2021-07-19 18:47:24JelleZijlstrasetrecipients: + JelleZijlstra, gvanrossum, levkivskyi, uriyyo, joperez, domdfcoding, kj
2021-07-19 18:47:24JelleZijlstrasetmessageid: <>
2021-07-19 18:47:24JelleZijlstralinkissue44353 messages
2021-07-19 18:47:24JelleZijlstracreate