Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > comp.lang.python > #39736

Re: Python Newbie

Path csiph.com!usenet.pasdenom.info!weretis.net!feeder1.news.weretis.net!feeder.erje.net!eu.feeder.erje.net!xlned.com!feeder7.xlned.com!news2.euro.net!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; 'python,': 0.02; 'explicitly': 0.04; 'subject:Python': 0.05; 'javascript,': 0.07; 'variable,': 0.07; 'variables.': 0.07; 'python': 0.09; '"a"': 0.09; 'braces': 0.09; 'globals': 0.09; 'received:151': 0.09; 'received:80.91': 0.09; 'received:80.91.229': 0.09; 'received:gmane.org': 0.09; 'received:list': 0.09; 'true),': 0.09; 'file,': 0.15; '"if"': 0.16; 'created.': 0.16; 'curly': 0.16; 'declaration,': 0.16; 'foo()': 0.16; 'javascript)': 0.16; 'notably': 0.16; 'received:80.91.229.3': 0.16; 'received:net24.it': 0.16; 'received:plane.gmane.org': 0.16; 'scope,': 0.16; 'wrote:': 0.17; 'variable': 0.20; 'define': 0.20; 'file.': 0.20; 'implicit': 0.22; 'statement': 0.23; '(this': 0.24; 'project,': 0.24; 'least': 0.25; 'header:User-Agent:1': 0.26; 'common': 0.26; '(most': 0.27; '(such': 0.27; 'see,': 0.27; "doesn't": 0.28; 'header:X-Complaints-To:1': 0.28; 'optional': 0.29; 'definition': 0.29; 'keyword': 0.30; 'function': 0.30; 'code': 0.31; 'point': 0.31; '(and': 0.32; 'accessible': 0.33; 'to:addr:python-list': 0.33; 'there': 0.35; 'received:org': 0.36; 'but': 0.36; 'itself': 0.37; 'one,': 0.37; 'two': 0.37; 'moment': 0.37; 'subject:: ': 0.38; 'some': 0.38; 'instead': 0.39; 'to:addr:python.org': 0.39; 'header:Received:5': 0.40; 'think': 0.40; 'your': 0.60; 'most': 0.61; 'first': 0.61; 'email addr:gmail.com': 0.63; 'within': 0.64; '*really*': 0.84
X-Injected-Via-Gmane http://gmane.org/
To python-list@python.org
From Vito De Tullio <vito.detullio@gmail.com>
Subject Re: Python Newbie
Date Sun, 24 Feb 2013 09:23:41 +0100
References <cad0eacc-6040-4a00-bd05-7fabfd2fa70e@googlegroups.com> <5c262e95-b3a8-4f2a-b752-84b30bf4f81e@googlegroups.com>
Mime-Version 1.0
Content-Type text/plain; charset="ISO-8859-1"
Content-Transfer-Encoding 7Bit
X-Gmane-NNTP-Posting-Host adsl-ull-166-216.50-151.net24.it
User-Agent KNode/4.10
X-BeenThere python-list@python.org
X-Mailman-Version 2.1.15
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.2396.1361694253.2939.python-list@python.org> (permalink)
Lines 58
NNTP-Posting-Host 2001:888:2000:d::a6
X-Trace 1361694253 news.xs4all.nl 6862 [2001:888:2000:d::a6]:45163
X-Complaints-To abuse@xs4all.nl
Xref csiph.com comp.lang.python:39736

Show key headers only | View raw


piterrr.dolinski@gmail.com wrote:

> You see, Javascript, for one, behaves the same way as Python (no variable
> declaration) but JS has curly braces and you know the variable you have
> just used is limited in scope to the code within the { }. With Python, you
> have to search the whole file.

I don't know if you know javascript, but I think your experience with it is 
limited, as you listed two of of the many common pitfalls of javascript:

javascript has optional variable declaration, but if you don't declare a 
variable (such as a local variable in a function) it binds itself in the 
global scope;

in c/c++/c#/java... curly braces define a new scope, in javascript no.

if you do in javascript

    function foo() {
        if (some condition) {
           a = 'something';
        }

        alert(a);
    }

the moment you call the foo() function (and some condition is true), a 
global variable "a" is created. (this time you *really* need to search not 
the whole .js file, but the whole project, as there is no "file-level" 
globals in javascript)

if you instead use the 'var' keyword to define explicitly a local variable

    function foo() {
        if (some condition) {
           var a = 'something';
        }

        alert(a);
    }

while you don't create a global variable, the "a" variable is still 
accessible outside the "if" braces.

this is the reason most javascript linters (most notably jslint) force the 
first statement of every function to be the definition of all function 
variables.



by this point of view, python and javascript have the same philosophy, but 
at least python doesn't allow implicit global variable definition


-- 
ZeD

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


Thread

Python Newbie Piterrr <piterrr.dolinski@gmail.com> - 2013-02-21 13:26 -0800
  Re: Python Newbie Ian Kelly <ian.g.kelly@gmail.com> - 2013-02-21 14:54 -0700
  Re: Python Newbie MRAB <python@mrabarnett.plus.com> - 2013-02-21 21:58 +0000
  Re: Python Newbie Chris Angelico <rosuav@gmail.com> - 2013-02-22 08:59 +1100
  Re: Python Newbie Peter Pearson <ppearson@nowhere.invalid> - 2013-02-21 22:03 +0000
  Re: Python Newbie Dave Angel <davea@davea.name> - 2013-02-21 17:22 -0500
  Re: Python Newbie piterrr.dolinski@gmail.com - 2013-02-21 14:40 -0800
    Re: Python Newbie Chris Angelico <rosuav@gmail.com> - 2013-02-22 10:21 +1100
      Re: Python Newbie piterrr.dolinski@gmail.com - 2013-02-21 15:34 -0800
        Re: Python Newbie Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-02-21 23:48 +0000
        Re: Python Newbie Chris Angelico <rosuav@gmail.com> - 2013-02-22 11:32 +1100
        Re: Python Newbie Michael Torrie <torriem@gmail.com> - 2013-02-23 11:58 -0700
      Re: Python Newbie piterrr.dolinski@gmail.com - 2013-02-21 15:34 -0800
    Re: Python Newbie Oscar Benjamin <oscar.j.benjamin@gmail.com> - 2013-02-21 23:27 +0000
    Re: Python Newbie Ian Kelly <ian.g.kelly@gmail.com> - 2013-02-21 16:55 -0700
    Re: Python Newbie rusi <rustompmody@gmail.com> - 2013-02-21 22:57 -0800
    Re: Python Newbie Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-02-22 10:26 +0000
      Re: Python Newbie Steve Simmons <square.steve@gmail.com> - 2013-02-22 12:05 +0100
      Re: Python Newbie Chris Angelico <rosuav@gmail.com> - 2013-02-22 22:23 +1100
    Re: Python Newbie Michael Torrie <torriem@gmail.com> - 2013-02-23 16:04 -0700
    Re: Python Newbie Vito De Tullio <vito.detullio@gmail.com> - 2013-02-24 09:23 +0100
    Re: Python Newbie "J.R." <groups_jr-1@yahoo.com.br> - 2013-02-24 23:02 -0300
      Re: Python Newbie Roy Smith <roy@panix.com> - 2013-02-24 21:03 -0500
        Re: Python Newbie "J.R." <groups_jr-1@yahoo.com.br> - 2013-02-24 23:35 -0300
        Re: Python Newbie Chris Angelico <rosuav@gmail.com> - 2013-02-25 13:31 +1100
  Re: Python Newbie Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2013-02-21 19:35 -0500
  Re: Python Newbie Mitya Sirenef <msirenef@lightbird.net> - 2013-02-21 23:50 -0500
    Re: Python Newbie Rui Maciel <rui.maciel@gmail.com> - 2013-02-22 11:58 +0000
      Re: Python Newbie Chris Angelico <rosuav@gmail.com> - 2013-02-22 23:12 +1100
        Re: Python Newbie Rui Maciel <rui.maciel@gmail.com> - 2013-02-22 13:50 +0000
          Re: Python Newbie Chris Angelico <rosuav@gmail.com> - 2013-02-23 01:05 +1100
            Re: Python Newbie Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-02-23 00:03 +0000
              Re: Python Newbie Chris Angelico <rosuav@gmail.com> - 2013-02-23 11:21 +1100
          Re: Python Newbie Duncan Booth <duncan.booth@invalid.invalid> - 2013-02-22 14:26 +0000
            Re: Python Newbie Steve Simmons <square.steve@gmail.com> - 2013-02-22 15:45 +0100
              Re: Python Newbie Duncan Booth <duncan.booth@invalid.invalid> - 2013-02-22 15:02 +0000
            Re: Python Newbie Chris Angelico <rosuav@gmail.com> - 2013-02-23 02:06 +1100
              Re: Python Newbie piterrr.dolinski@gmail.com - 2013-02-22 13:37 -0800
                Re: Python Newbie Oscar Benjamin <oscar.j.benjamin@gmail.com> - 2013-02-22 22:08 +0000
                Re: Python Newbie Ian Kelly <ian.g.kelly@gmail.com> - 2013-02-22 15:45 -0700
                Re: Python Newbie piterrr.dolinski@gmail.com - 2013-02-22 15:38 -0800
                Re: Python Newbie Chris Angelico <rosuav@gmail.com> - 2013-02-23 11:17 +1100
                Re: Python Newbie Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2013-02-23 13:29 -0500
                Re: Python Newbie Chris Angelico <rosuav@gmail.com> - 2013-02-24 08:38 +1100
                Re: Python Newbie Michael Torrie <torriem@gmail.com> - 2013-02-23 15:52 -0700
                Re: Python Newbie Chris Angelico <rosuav@gmail.com> - 2013-02-24 10:18 +1100
                Re: Python Newbie piterrr.dolinski@gmail.com - 2013-02-23 15:46 -0800
                Re: Python Newbie Larry Hudson <orgnut@yahoo.com> - 2013-02-23 20:20 -0800
                Re: Python Newbie Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-02-24 14:34 +0000
                Re: Python Newbie piterrr.dolinski@gmail.com - 2013-02-24 07:46 -0800
                Re: Python Newbie Chris Angelico <rosuav@gmail.com> - 2013-02-25 02:52 +1100
                Re: Python Newbie Roy Smith <roy@panix.com> - 2013-02-24 11:22 -0500
                Re: Python Newbie Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-02-24 17:44 +0000
                Re: Python Newbie piterrr.dolinski@gmail.com - 2013-02-24 11:29 -0800
                Re: Python Newbie Joshua Landau <joshua.landau.ws@gmail.com> - 2013-02-24 21:35 +0000
                Re: Python Newbie piterrr.dolinski@gmail.com - 2013-02-24 14:43 -0800
                Re: Python Newbie Joel Goldstick <joel.goldstick@gmail.com> - 2013-02-24 18:05 -0500
                Re: Python Newbie Joshua Landau <joshua.landau.ws@gmail.com> - 2013-02-24 23:13 +0000
                Re: Python Newbie piterrr.dolinski@gmail.com - 2013-02-24 14:43 -0800
                Re: Python Newbie Larry Hudson <orgnut@yahoo.com> - 2013-02-26 00:32 -0800
                Re: Python Newbie rurpy@yahoo.com - 2013-02-26 10:23 -0800
                Re: Python Newbie Ethan Furman <ethan@stoneleaf.us> - 2013-02-26 10:59 -0800
                Re: Python Newbie rurpy@yahoo.com - 2013-02-26 13:30 -0800
                Re: Python Newbie Michael Torrie <torriem@gmail.com> - 2013-02-24 18:31 -0700
                Re: Python Newbie Chris Angelico <rosuav@gmail.com> - 2013-02-25 09:08 +1100
                Re: Python Newbie Oscar Benjamin <oscar.j.benjamin@gmail.com> - 2013-02-24 23:18 +0000
                Re: Python Newbie Joshua Landau <joshua.landau.ws@gmail.com> - 2013-02-24 22:51 +0000
                Re: Python Newbie piterrr.dolinski@gmail.com - 2013-02-24 15:38 -0800
                Re: Python Newbie Chris Angelico <rosuav@gmail.com> - 2013-02-25 10:45 +1100
                Re: Python Newbie Ethan Furman <ethan@stoneleaf.us> - 2013-02-24 15:53 -0800
                Re: Python Newbie piterrr.dolinski@gmail.com - 2013-02-24 16:08 -0800
                Re: Python Newbie Joshua Landau <joshua.landau.ws@gmail.com> - 2013-02-25 00:28 +0000
                Re: Python Newbie Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-02-25 00:38 +0000
                Re: Python Newbie Ethan Furman <ethan@stoneleaf.us> - 2013-02-24 16:33 -0800
                Re: Python Newbie Oscar Benjamin <oscar.j.benjamin@gmail.com> - 2013-02-25 00:45 +0000
                Re: Python Newbie Roy Smith <roy@panix.com> - 2013-02-24 19:50 -0500
                Re: Python Newbie Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-02-25 01:04 +0000
                Re: Python Newbie Chris Angelico <rosuav@gmail.com> - 2013-02-25 12:27 +1100
                Re: Python Newbie Michael Torrie <torriem@gmail.com> - 2013-02-24 18:42 -0700
                Re: Python Newbie Chris Angelico <rosuav@gmail.com> - 2013-02-25 12:24 +1100
                Re: Python Newbie Oscar Benjamin <oscar.j.benjamin@gmail.com> - 2013-02-25 01:44 +0000
                Re: Python Newbie Chris Angelico <rosuav@gmail.com> - 2013-02-25 12:53 +1100
                Re: Python Newbie MRAB <python@mrabarnett.plus.com> - 2013-02-25 02:23 +0000
                Re: Python Newbie Ethan Furman <ethan@stoneleaf.us> - 2013-02-24 18:59 -0800
                Re: Python Newbie piterrr.dolinski@gmail.com - 2013-02-24 16:08 -0800
                Re: Python Newbie Roy Smith <roy@panix.com> - 2013-02-24 19:42 -0500
                Re: Python Newbie piterrr.dolinski@gmail.com - 2013-02-24 15:38 -0800
                Re: Python Newbie Joshua Landau <joshua.landau.ws@gmail.com> - 2013-02-24 23:21 +0000
                Re: Python Newbie Dave Angel <davea@davea.name> - 2013-02-24 17:47 -0500
                Re: Python Newbie Serhiy Storchaka <storchaka@gmail.com> - 2013-02-25 14:40 +0200
                Re: Python Newbie piterrr.dolinski@gmail.com - 2013-02-24 07:46 -0800
                Re: Python Newbie Michael Torrie <torriem@gmail.com> - 2013-02-23 22:23 -0700
                Re: Python Newbie MRAB <python@mrabarnett.plus.com> - 2013-02-24 00:11 +0000
                Re: Python Newbie Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2013-02-24 12:37 -0500
                Re: Python Newbie Michael Torrie <torriem@gmail.com> - 2013-02-24 10:56 -0700
                Re: Python Newbie Roy Smith <roy@panix.com> - 2013-02-24 13:07 -0500
                Re: Python Newbie Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2013-02-24 21:01 -0500
                Re: Python Newbie piterrr.dolinski@gmail.com - 2013-02-22 15:38 -0800
                Re: Python Newbie Terry Reedy <tjreedy@udel.edu> - 2013-02-22 20:04 -0500
                Re: Python Newbie rurpy@yahoo.com - 2013-02-22 18:48 -0800
                Re: Python Newbie Mitya Sirenef <msirenef@lightbird.net> - 2013-02-22 20:47 -0500
                Re: Python Newbie Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-02-23 02:02 +0000
                Re: Python Newbie Chris Angelico <rosuav@gmail.com> - 2013-02-23 13:18 +1100
                Re: Python Newbie Grant Edwards <invalid@invalid.invalid> - 2013-02-24 18:19 +0000
                Re: Python Newbie Chris Angelico <rosuav@gmail.com> - 2013-02-25 07:25 +1100
                Re: Python Newbie Mitya Sirenef <msirenef@lightbird.net> - 2013-02-22 21:40 -0500
                Re: Python Newbie Chris Angelico <rosuav@gmail.com> - 2013-02-23 13:48 +1100
                Re: Python Newbie Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-02-23 02:59 +0000
                Re: Python Newbie Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2013-02-23 13:34 -0500
                Re: Python Newbie Chris Angelico <rosuav@gmail.com> - 2013-02-24 08:40 +1100
                Re: Python Newbie Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2013-02-24 12:41 -0500
                Re: Python Newbie Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-02-23 04:13 +0000
                Re: Python Newbie Serhiy Storchaka <storchaka@gmail.com> - 2013-02-23 11:48 +0200
                Re: Python Newbie Rui Maciel <rui.maciel@gmail.com> - 2013-02-23 12:30 +0000
                Re: Python Newbie Steve Simmons <square.steve@gmail.com> - 2013-02-23 16:43 +0100
                Re: Python Newbie jmfauth <wxjmfauth@gmail.com> - 2013-02-23 10:44 -0800
                Re: Python Newbie Ian Kelly <ian.g.kelly@gmail.com> - 2013-02-23 12:13 -0700
                Re: Python Newbie Ethan Furman <ethan@stoneleaf.us> - 2013-02-23 11:08 -0800
                Re: Python Newbie jmfauth <wxjmfauth@gmail.com> - 2013-02-23 12:53 -0800
                Re: Python Newbie Chris Angelico <rosuav@gmail.com> - 2013-02-24 08:48 +1100
                Re: Python Newbie Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-02-24 00:02 +0000
                Re: Python Newbie Michael Torrie <torriem@gmail.com> - 2013-02-23 12:16 -0700
                Re: Python Newbie Matej Cepl <mcepl@redhat.com> - 2013-02-24 00:06 +0100
                Re: Python Newbie Chris Angelico <rosuav@gmail.com> - 2013-02-24 02:51 +1100
                Re: Python Newbie Matej Cepl <mcepl@redhat.com> - 2013-02-24 00:04 +0100
                Re: Python Newbie Ethan Furman <ethan@stoneleaf.us> - 2013-02-23 08:32 -0800
                Re: Python Newbie Steve Simmons <square.steve@gmail.com> - 2013-02-23 18:39 +0100
                Re: Python Newbie Michael Torrie <torriem@gmail.com> - 2013-02-23 12:19 -0700
                Re: Python Newbie Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-02-24 17:11 +0000
                Re: Python Newbie piterrr.dolinski@gmail.com - 2013-02-24 11:40 -0800
                Re: Python Newbie Mitya Sirenef <msirenef@lightbird.net> - 2013-02-24 15:06 -0500
                Re: Python Newbie "Michael Ross" <gmx@ross.cx> - 2013-02-24 21:33 +0100
                Re: Python Newbie MRAB <python@mrabarnett.plus.com> - 2013-02-24 20:34 +0000
                Re: Python Newbie Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-02-24 20:41 +0000
                Re: Python Newbie Ethan Furman <ethan@stoneleaf.us> - 2013-02-24 12:34 -0800
                Re: Python Newbie Chris Angelico <rosuav@gmail.com> - 2013-02-25 07:42 +1100
                Re: Python Newbie Roy Smith <roy@panix.com> - 2013-02-24 15:48 -0500
                Re: Python Newbie Joshua Landau <joshua.landau.ws@gmail.com> - 2013-02-24 21:58 +0000
                Re: Python Newbie Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2013-02-24 21:08 -0500
                Re: Python Newbie Joshua Landau <joshua.landau.ws@gmail.com> - 2013-02-25 02:59 +0000
                Re: Python Newbie Chris Angelico <rosuav@gmail.com> - 2013-02-25 07:47 +1100
                Re: Python Newbie Chris Angelico <rosuav@gmail.com> - 2013-02-25 07:58 +1100
                Re: Python Newbie Roy Smith <roy@panix.com> - 2013-02-24 16:08 -0500
                Re: Python Newbie Chris Angelico <rosuav@gmail.com> - 2013-02-25 08:44 +1100
                Re: Python Newbie Mitya Sirenef <msirenef@lightbird.net> - 2013-02-24 17:40 -0500
                Re: Python Newbie Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-02-25 01:11 +0000
                Re: Python Newbie Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-02-25 00:42 +0000
                Re: Python Newbie Michael Torrie <torriem@gmail.com> - 2013-02-24 18:34 -0700
                Re: Python Newbie Ethan Furman <ethan@stoneleaf.us> - 2013-02-24 14:33 -0800
                Re: Python Newbie Albert Hopkins <marduk@letterboxes.org> - 2013-02-24 18:32 -0500
                Re: Python Newbie Chris Angelico <rosuav@gmail.com> - 2013-02-25 10:44 +1100
                Re: Python Newbie Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-02-25 01:06 +0000
                Re: Python Newbie piterrr.dolinski@gmail.com - 2013-02-24 11:40 -0800
              Re: Python Newbie piterrr.dolinski@gmail.com - 2013-02-22 13:37 -0800
      Re: Python Newbie Mitya Sirenef <msirenef@lightbird.net> - 2013-02-22 20:05 -0500
  Re: Python Newbie Gene Heskett <gheskett@wdtv.com> - 2013-02-23 12:32 -0500
  Re: Python Newbie Steve Simmons <square.steve@gmail.com> - 2013-02-23 19:10 +0100
  Re: Python Newbie Michael Torrie <torriem@gmail.com> - 2013-02-23 11:40 -0700
  Re: Python Newbie Michael Torrie <torriem@gmail.com> - 2013-02-23 12:15 -0700
  Re: Python Newbie Gene Heskett <gheskett@wdtv.com> - 2013-02-23 17:49 -0500
  Re: Python Newbie Nick Mellor <thebalancepro@gmail.com> - 2013-02-25 19:37 -0800

csiph-web