Path: csiph.com!fu-berlin.de!uni-berlin.de!not-for-mail
From: Kevin Conway <kevinjacobconway@gmail.com>
Newsgroups: comp.lang.python
Subject: Re: Namespaces are one honking great idea
Date: Sat, 02 Jul 2016 15:34:08 +0000
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Message-ID: <mailman.27.1467473666.2295.python-list@python.org>
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> staticmethod isn't technically required to use a method through the class
(or subclasses), it simply provides the appropriate magic to allow it to be
called through instances.

For example, the following code covers all described use cases of the
proposed namespace. Methods are invoked without creating instances and
state is managed on the class object directly.

class CustomNs:

    stateful_data = 1

    @staticmethod
    def echo(text):
        print(text)

    @classmethod
    def mutate(cls):
        cls.stateful_data += 1
        print(cls.stateful_data)

CustomNs.echo("test")
print(CustomNs.stateful_data)
CustomNs.mutate()
print(CustomNs.stateful_data)

For the proponents of namespace, what is deficient in the above example
that necessitates a language change?

On Sat, Jul 2, 2016, 00:02 Random832 <random832@fastmail.com> wrote:

> On Fri, Jul 1, 2016, at 21:50, Kevin Conway wrote:
> > I believe the namespace object you are referring to is exactly a
> > class. IIRC, classes came about as a "module in a module".
>
> No, because classes have instances. And conceptually they seem like they
> *should* have instances. Just using the term "class" carries
> expectations.
>
> More to the point, what modules do that classes do not is provide a
> global namespace for functions defined within them, so that variables
> within them can be used (well, read - writing them requires a
> declaration) by the functions without extra qualification.
>
> > Regardless, all use cases you've listed are already satisfied by use
> > of the static and class method decorators. Methods decorated with
> > these do not require an instance initialization to use.
>
> staticmethod isn't technically required to use a method through the
> class (or subclasses), it simply provides the appropriate magic to allow
> it to be called through instances.
> --
> https://mail.python.org/mailman/listinfo/python-list
>