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Re: Using decorators with argument in Python

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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

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Thread

Using decorators with argument in Python Jigar Tanna <poisonousrattle5@gmail.com> - 2011-06-28 09:52 -0700
  Re: Using decorators with argument in Python Lie Ryan <lie.1296@gmail.com> - 2011-06-29 03:06 +1000
    Re: Using decorators with argument in Python John Posner <jjposner@codicesoftware.com> - 2011-06-29 13:23 -0400
    Re: Using decorators with argument in Python Ethan Furman <ethan@stoneleaf.us> - 2011-06-29 12:30 -0700
    Re: Using decorators with argument in Python Ian Kelly <ian.g.kelly@gmail.com> - 2011-06-29 13:29 -0600
    Re: Using decorators with argument in Python Ethan Furman <ethan@stoneleaf.us> - 2011-06-29 14:29 -0700
    Re: Using decorators with argument in Python Ian Kelly <ian.g.kelly@gmail.com> - 2011-06-29 15:26 -0600
    Re: Using decorators with argument in Python Ethan Furman <ethan@stoneleaf.us> - 2011-06-29 14:51 -0700
    Re: Using decorators with argument in Python Duncan Booth <duncan.booth@invalid.invalid> - 2011-06-30 09:00 +0000
    Re: Using decorators with argument in Python John Posner <jjposner@codicesoftware.com> - 2011-07-01 11:18 -0400
  Re: Using decorators with argument in Python Ian Kelly <ian.g.kelly@gmail.com> - 2011-06-28 11:20 -0600
  Re: Using decorators with argument in Python Ben Finney <ben+python@benfinney.id.au> - 2011-06-29 08:19 +1000

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