Do we need _pyio at all?
Does PyPy or any other Python implementation use it?

On Wed, Mar 31, 2021 at 9:36 PM Victor Stinner <vstinner@python.org> wrote:
>
> Hi,
>
> The io module provides an open() function. It also provides an
> OpenWrapper which only exists to be able to store open as a method
> (class or instance method). In the _pyio module, pure Python
> implementation of the io module, OpenWrapper is implemented as:
>
> class OpenWrapper:
>     """Wrapper for builtins.open
>
>     Trick so that open won't become a bound method when stored
>     as a class variable (as dbm.dumb does).

>
>     See initstdio() in Python/pylifecycle.c.
>     """
>     def __new__(cls, *args, **kwargs):
>         return open(*args, **kwargs)
>
> I would like to remove this class which is causing troubles in the PEP
> 597 implementation, but I don't know how. Simplified problem:
> ---
> def func():
>     print("my func")
>
> class MyClass:
>     method = func
>
> func() # A
> MyClass.method() # B
> obj = MyClass()
> obj.method() # C
> ---
>
> With this syntax, A and B work, but C fails with TypeError: func()
> takes 0 positional arguments but 1 was given.
>
> If I decorate func() with @staticmethod, B and C work, but A fails
> with TypeError: 'staticmethod' object is not callable.
>
> Is OpenWrapper the only way to have a callable object which works in
> the 3 variants A, B and C?
>
> A, B and C work if MyClass is modified to use staticmethod:
>
> class MyClass:
>     method = staticmethod(func)
>
> Victor
> --
> Night gathers, and now my watch begins. It shall not end until my death.
> _______________________________________________
> Python-Dev mailing list -- python-dev@python.org
> To unsubscribe send an email to python-dev-leave@python.org
> https://mail.python.org/mailman3/lists/python-dev.python.org/
> Message archived at https://mail.python.org/archives/list/python-dev@python.org/message/QZ7SFW3IW3S2C5RMRJZOOUFSHHUINNME/
> Code of Conduct: http://python.org/psf/codeofconduct/



--
Inada Naoki  <songofacandy@gmail.com>
_______________________________________________
Python-Dev mailing list -- python-dev@python.org
To unsubscribe send an email to python-dev-leave@python.org
https://mail.python.org/mailman3/lists/python-dev.python.org/
Message archived at https://mail.python.org/archives/list/python-dev@python.org/message/BOSZENKZRZCTIYWDRBRLWT4GKHWGDLWP/
Code of Conduct: http://python.org/psf/codeofconduct/