decorator module in stdlib? (original) (raw)

Daniel Fetchinson

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Apr 6, 2009, 8:41:33 PM4/6/09

to Python

The decorator module [1] written by Michele Simionato is a very useful
tool for maintaining function signatures while applying a decorator.
Many different projects implement their own versions of the same
functionality, for example turbogears has its own utility for this, I
guess others do something similar too.

Was the issue whether to include this module in the stdlib raised? If
yes, what were the arguments against it? If not, what do you folks
think, shouldn't it be included? I certainly think it should be.

Cheers,
Daniel

[1] http://pypi.python.org/pypi/decorator

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Chris Rebert

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Apr 6, 2009, 8:50:05 PM4/6/09

to Daniel Fetchinson, Python

On Mon, Apr 6, 2009 at 5:41 PM, Daniel Fetchinson
<fetch...@googlemail.com> wrote:
> The decorator module [1] written by Michele Simionato is a very useful
> tool for maintaining function signatures while applying a decorator.
> Many different projects implement their own versions of the same
> functionality, for example turbogears has its own utility for this, I
> guess others do something similar too.
>
> Was the issue whether to include this module in the stdlib raised? If
> yes, what were the arguments against it? If not, what do you folks
> think, shouldn't it be included? I certainly think it should be.

Similar functionality is already provided by
functools.update_wrapper() and functools.wraps().
See http://docs.python.org/library/functools.html
You might consider proposing the modification of these functions instead.

Cheers,
Chris

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Michele Simionato

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Apr 7, 2009, 12:20:02 AM4/7/09

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On Apr 7, 2:50 am, Chris Rebert <c...@rebertia.com> wrote:
> Similar functionality is already provided by
> functools.update_wrapper() and functools.wraps().

> Seehttp://docs.python.org/library/functools.html

> You might consider proposing the modification of these functions instead.

Unfortunately functools.update_wrapper() and functools.wraps()
are NOT equivalent to the decorator module. My original
plan when I wrote the decorator module was to make aware
people that the corrent support for decorators in the language
is insufficient. I have always seen the decorator module
as a temporary hack waiting for a proper solution
at the language level. I wanted the possibility to modify the
signature of a function. Everybody more or less agreed
that this was a good idea on python-dev, and there is
also a PEP:

http://www.python.org/dev/peps/pep-0362/

However, AFAIK, the PEP is still in draft status.
Perhaps people wanting this should make some noise
on python-dev.

Michele Simionato

Daniel Fetchinson

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Apr 7, 2009, 1:57:26 AM4/7/09

to Python

>> Similar functionality is already provided by
>> functools.update_wrapper() and functools.wraps().
>> Seehttp://docs.python.org/library/functools.html
>> You might consider proposing the modification of these functions instead.
>
> Unfortunately functools.update_wrapper() and functools.wraps()
> are NOT equivalent to the decorator module.

Exactly, that's why I think the decorator module would be a useful
addition to functools.

> My original
> plan when I wrote the decorator module was to make aware
> people that the corrent support for decorators in the language
> is insufficient. I have always seen the decorator module
> as a temporary hack waiting for a proper solution
> at the language level. I wanted the possibility to modify the
> signature of a function. Everybody more or less agreed
> that this was a good idea on python-dev, and there is
> also a PEP:
>
> http://www.python.org/dev/peps/pep-0362/
>
> However, AFAIK, the PEP is still in draft status.
> Perhaps people wanting this should make some noise
> on python-dev.

I've posted it to python-dev:

http://mail.python.org/pipermail/python-dev/2009-April/088387.html

Cheers,
Daniel

Michele Simionato

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Apr 7, 2009, 2:12:58 AM4/7/09

to

On Apr 7, 7:57 am, Daniel Fetchinson <fetchin...@googlemail.com>
wrote:

> > have always seen the decorator module
> > as a temporary hack waiting for a proper solution
> > at the language level. I wanted the possibility to modify the
> > signature of a function. Everybody more or less agreed
> > that this was a good idea on python-dev, and there is
> > also a PEP:
>
> >http://www.python.org/dev/peps/pep-0362/
>
> > However, AFAIK, the PEP is still in draft status.
> > Perhaps people wanting this should make some noise
> > on python-dev.
>
> I've posted it to python-dev:
>
> http://mail.python.org/pipermail/python-dev/2009-April/088387.html

If the PEP is implemented and it becomes possible
to fiddle with the function signature directly,
then the decorator module would become trivial
to implement and actually nearly useless.
I would happy with that, less code to maintain ;)