On Sat, Sep 22, 2018 at 3:11 PM Guido van Rossum wrote:
[..]
> Still, I wonder if there's a tweak possible of the globals and locals used
> when exec()'ing the function definitions in dataclasses.py, so that
> get_type_hints() gets the right globals for this use case.
>
> It's really tough to
On Sat, Sep 22, 2018 at 11:29 AM Eric V. Smith wrote:
> I think this problem is endemic to get_type_hints(). I've never
> understood how you're supposed to use the globals and locals arguments
> to it, but this works:
>
> print(get_type_hints(Bar.__init__, globals()))
>
> as does:
>
>
On 9/22/2018 12:41 PM, Guido van Rossum wrote:
This is a good catch -- thanks for bringing it up. I'm adding Eric Smith
(author of dataclasses) and Ivan Levkivskyi (co-author of typing) as
well as Łukasz Langa (author of PEP 563) to the thread to see if they
have further insights.
I don't
This is a good catch -- thanks for bringing it up. I'm adding Eric Smith
(author of dataclasses) and Ivan Levkivskyi (co-author of typing) as well
as Łukasz Langa (author of PEP 563) to the thread to see if they have
further insights.
Personally I don't think it's feasible to change PEP 563 to
The new postponed annotations have an unexpected interaction with
dataclasses. Namely, you cannot get the type hints of any of the data
classes methods.
For example, I have some code that inspects the type parameters of a
class's `__init__` method. (The real use case is to provide a default
