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From: Ian Kelly <ian.g.kelly@gmail.com>
Date: Tue, 28 Jun 2011 11:20:29 -0600
Subject: Re: Using decorators with argument in Python
To: Jigar Tanna <poisonousrattle5@gmail.com>
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On Tue, Jun 28, 2011 at 10:52 AM, Jigar Tanna
<poisonousrattle5@gmail.com> wrote:
> coming across to certain views from people, it is not a good practice
> to use
> decorators with arguments (i.e. @memoize() ) and instead it is good to
> just
> use @memoize. Can any of you guys explain me advantages and
> disadvantages of
> using each of them

The main concern I think is not with how the decorators are used but
how they are designed.  An argument-less decorator will normally be
used as @memoize, and @memoize() will likely not work.  A decorator
with arguments that are all optional will normally be used as
@memoize(), and @memoize will likely not work.  This naturally leads
to some confusion: do I need parentheses to use this particular
decorator or not?

As a personal design goal I try to make my decorators either take at
least one required argument or take no arguments at all.  This way
it's either @memoize or @memoize(foo), but never just the confusing
@memoize().

Cheers,
Ian