Re: Is this unpythonic?

Path	csiph.com!usenet.pasdenom.info!weretis.net!feeder1.news.weretis.net!feeder.erje.net!1.eu.feeder.erje.net!bcyclone04.am1.xlned.com!bcyclone04.am1.xlned.com!newsfeed.xs4all.nl!newsfeed3a.news.xs4all.nl!xs4all!post.news.xs4all.nl!not-for-mail
Return-Path	<python-python-list@m.gmane.org>
X-Original-To	python-list@python.org
Delivered-To	python-list@mail.python.org
X-Spam-Status	OK 0.007
X-Spam-Evidence	'H': 0.99; 'S': 0.00; 'argument': 0.05; 'modify': 0.07; "(i'd": 0.09; 'promising': 0.09; 'received:80.91': 0.09; 'received:80.91.229': 0.09; 'received:gmane.org': 0.09; 'received:list': 0.09; 'def': 0.12; 'wrote': 0.14; 'flow,': 0.16; 'received:80.91.229.3': 0.16; 'received:plane.gmane.org': 0.16; 'thereby': 0.16; 'appropriate': 0.16; 'thanks,': 0.17; 'wrote:': 0.18; 'tend': 0.24; 'define': 0.26; 'header:X-Complaints-To:1': 0.27; 'am,': 0.29; 'but': 0.35; 'subject:?': 0.36; 'list': 0.37; 'list.': 0.37; 'to:addr:python-list': 0.38; 'to:addr:python.org': 0.39; 'received:org': 0.40; "you're": 0.61; 'decided': 0.64; 'frank': 0.68; 'nobody': 0.68; 'default': 0.69; 'subject:this': 0.83; 'acceptable)': 0.84; 'trick,': 0.84; 'trick.': 0.84
X-Injected-Via-Gmane	http://gmane.org/
To	python-list@python.org
From	"Frank Millman" <frank@chagford.com>
Subject	Re: Is this unpythonic?
Date	Fri, 8 May 2015 15:12:11 +0200
References	<mailman.224.1431072121.12865.python-list@python.org> <554c8b0a$0$12992$c3e8da3$5496439d@news.astraweb.com> <mii4il$vv$1@ger.gmane.org> <554CA652.1000607@davea.name>
X-Gmane-NNTP-Posting-Host	197.86.223.132
X-MSMail-Priority	Normal
X-Newsreader	Microsoft Outlook Express 6.00.3790.4657
X-RFC2646	Format=Flowed; Response
X-MimeOLE	Produced By Microsoft MimeOLE V6.00.3790.4913
X-BeenThere	python-list@python.org
X-Mailman-Version	2.1.20+
Precedence	list
List-Id	General discussion list for the Python programming language <python-list.python.org>
List-Unsubscribe	<https://mail.python.org/mailman/options/python-list>, <mailto:python-list-request@python.org?subject=unsubscribe>
List-Archive	<http://mail.python.org/pipermail/python-list/>
List-Post	<mailto:python-list@python.org>
List-Help	<mailto:python-list-request@python.org?subject=help>
List-Subscribe	<https://mail.python.org/mailman/listinfo/python-list>, <mailto:python-list-request@python.org?subject=subscribe>
Newsgroups	comp.lang.python
Message-ID	<mailman.250.1431090908.12865.python-list@python.org> (permalink)
Lines	29
NNTP-Posting-Host	2001:888:2000:d::a6
X-Trace	1431090908 news.xs4all.nl 2889 [2001:888:2000:d::a6]:44313
X-Complaints-To	abuse@xs4all.nl
X-Received-Bytes	3201
X-Received-Body-CRC	1796395431
Xref	csiph.com comp.lang.python:90168

Show key headers only | View raw

"Dave Angel" <davea@davea.name> wrote in message 
news:554CA652.1000607@davea.name...
> On 05/08/2015 06:53 AM, Frank Millman wrote:
>>
>
> It might be appropriate to define the list at top-level, as
>
> EMPTY_LIST=[]
>
> and in your default argument as
>     def x(y, z=EMPTY_LIST):
>
> and with the all-caps, you're thereby promising that nobody will modify 
> that list.
>
> (I'd tend to do the None trick, but I think this alternative would be 
> acceptable)
>

Thanks, Dave, I like that idea.

However, as you can see from my other replies, I have decided to go with the 
flow, and use the None trick.

Frank

Back to comp.lang.python | Previous | Next — Previous in thread | Find similar | Unroll thread

Thread

Is this unpythonic? "Frank Millman" <frank@chagford.com> - 2015-05-08 10:01 +0200
  Re: Is this unpythonic? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-05-08 20:08 +1000
    Re: Is this unpythonic? "Frank Millman" <frank@chagford.com> - 2015-05-08 12:53 +0200
      Re: Is this unpythonic? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-05-09 01:07 +1000
        Re: Is this unpythonic? "Frank Millman" <frank@chagford.com> - 2015-05-09 07:56 +0200
        Re: Is this unpythonic? "Frank Millman" <frank@chagford.com> - 2015-05-09 08:51 +0200
          Re: Is this unpythonic? Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2015-05-09 19:47 +1200
            Re: Is this unpythonic? "Frank Millman" <frank@chagford.com> - 2015-05-09 11:10 +0200
    Re: Is this unpythonic? Dave Angel <davea@davea.name> - 2015-05-08 08:04 -0400
      Re: Is this unpythonic? Johannes Bauer <dfnsonfsduifb@gmx.de> - 2015-05-10 10:04 +0200
        Re: Is this unpythonic? "Frank Millman" <frank@chagford.com> - 2015-05-10 10:58 +0200
          Re: Is this unpythonic? Johannes Bauer <dfnsonfsduifb@gmx.de> - 2015-05-10 11:54 +0200
            Re: Is this unpythonic? "Frank Millman" <frank@chagford.com> - 2015-05-10 12:40 +0200
    Re: Is this unpythonic? "Frank Millman" <frank@chagford.com> - 2015-05-08 15:12 +0200

csiph-web