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.
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