Path: csiph.com!fu-berlin.de!uni-berlin.de!not-for-mail
From: Michael Selik <michael.selik@gmail.com>
Newsgroups: comp.lang.python
Subject: Re: Design: Idiom for classes and methods that are customizable by the user?
Date: Tue, 17 May 2016 18:13:06 +0000
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On Tue, May 17, 2016 at 11:18 AM Dirk B=C3=A4chle <tshortik@gmx.de> wrote:

>
> > It's not so great to require
> > that the user must explicitly ``add`` their derived class after definin=
g
> > it. Perhaps that add function could be a decorator?
>
> Our current API doesn't use decorators at all, since it's also aimed at
> people with no (or only some) knowledge of Python.


I think you'll find that users of decorators do not need any special
knowledge. The Flask framework (http://flask.pocoo.org/) is proof of that.


> decorators...would have looked strange to the average user perhaps?
>

Many beginners are willing to mimic your example code without questioning
what that "@" thingy is doing above the function or class.

Compare that with trying to explain to a C++ user that in Python classes
are actually objects and you can pass them to the ``add`` function to
register them... that's going to take a while.

We're now free to add them into the mix for our new Python 2.7.x/3.y
> codebase, but this would probably require an API discussion
> first.
>

An alternative would be creating a TaskmasterMeta metaclass that registers
the Taskmaster subclass when it's defined. I'm a little reluctant to
recommend that one. I find decorators to be more elegant.