Path: csiph.com!x330-a1.tempe.blueboxinc.net!usenet.pasdenom.info!news.albasani.net!feeder.news-service.com!newsfeed.xs4all.nl!newsfeed6.news.xs4all.nl!xs4all!newsgate.cistron.nl!newsgate.news.xs4all.nl!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 0.000
X-Spam-Evidence: '*H*': 1.00; '*S*': 0.00; 'bug': 0.02; 'warnings': 0.05; '3.2': 0.07; 'function,': 0.07; 'terry': 0.07; 'python': 0.07; 'received:80.91': 0.09; 'received:80.91.229': 0.09; 'received:80.91.229.12': 0.09; 'received:gmane.org': 0.09; 'received:list': 0.09; 'received:lo.gmane.org': 0.09; 'usage.': 0.09; 'pm,': 0.11; 'wrote:': 0.14; 'defined': 0.15; 'expression,': 0.16; 'reedy': 0.16; 'subject:function': 0.16; 'usage': 0.20; 'jan': 0.22; 'code': 0.22; 'header:In-Reply-To:1': 0.22; 'filter': 0.22; '(and': 0.22; 'statement': 0.26; 'changed': 0.27; 'tried': 0.27; 'function': 0.27; 'hi,': 0.29; 'subject:?': 0.29; 'depends': 0.29; 'list': 0.30; 'enabled': 0.31; 'it.': 0.31; 'to:addr:python- list': 0.32; 'source': 0.32; 'header:X-Complaints-To:1': 0.34; 'header:User-Agent:1': 0.35; 'rather': 0.36; 'run': 0.37; 'faster': 0.38; 'but': 0.38; 'no.': 0.38; 'received:org': 0.38; 'unless': 0.38; 'to:addr:python.org': 0.39; 'header:Mime- Version:1': 0.39; 'would': 0.40; 'header:Received:5': 0.40; 'free': 0.62; 'today': 0.70; 'map)': 0.84; 'checker': 0.93
X-Injected-Via-Gmane: http://gmane.org/
To: python-list@python.org
From: Terry Reedy <tjreedy@udel.edu>
Subject: Re: Is the function filter deprecated?
Date: Wed, 06 Apr 2011 23:05:54 -0400
References: <BANLkTinGwY+jy_uP7Me-NDwDyf8DixPSQQ@mail.gmail.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit
X-Gmane-NNTP-Posting-Host: rain.gmane.org
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2.15) Gecko/20110303 Lightning/1.0b2 Thunderbird/3.1.9
In-Reply-To: <BANLkTinGwY+jy_uP7Me-NDwDyf8DixPSQQ@mail.gmail.com>
X-BeenThere: python-list@python.org
X-Mailman-Version: 2.1.12
Precedence: list
List-Id: General discussion list for the Python programming language <python-list.python.org>
List-Unsubscribe: <http://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: <http://mail.python.org/mailman/listinfo/python-list>, <mailto:python-list-request@python.org?subject=subscribe>
Newsgroups: comp.lang.python
Message-ID: <mailman.95.1302145569.9059.python-list@python.org>
Lines: 29
NNTP-Posting-Host: 82.94.164.166
X-Trace: 1302145569 news.xs4all.nl 81479 [::ffff:82.94.164.166]:39742
X-Complaints-To: abuse@xs4all.nl
Xref: x330-a1.tempe.blueboxinc.net comp.lang.python:2737

On 4/6/2011 7:20 PM, Jabba Laci wrote:
> Hi,
>
> I tried Pylint today and it gave me a warning for the function
> "filter".

That is a bug in PyLint. Do not take any code checker as gospel truth.

> Is it deprecated?

No. One can look in the source code for a deprecation warning statement 
or run 3.2 with deprecation warnings enabled and call it.

In Python 3, filter (and map) were changed to return iterables rather 
than lists.

 > Is the usage of list comprehensions encouraged?

Depends on the person and usage. If you already have the filter function 
defined filter(f,seq) is easier and to me clearer. If you do not have a 
filter function, but only an expression, and would not use it again, 
then (x for x in seq if expr) is faster and to me easier and clearer 
than filter(lambda x: expr, seq)

Feel free to take your pick unless part of a group with code guidelines.

-- 
Terry Jan Reedy