Path: csiph.com!fu-berlin.de!uni-berlin.de!not-for-mail
From: Ian Kelly <ian.g.kelly@gmail.com>
Newsgroups: comp.lang.python
Subject: Re: What is a function parameter =[] for?
Date: Tue, 24 Nov 2015 09:56:02 -0700
Lines: 44
Message-ID: <mailman.17.1448384205.20593.python-list@python.org>
References: <d9045bdd-a5d4-4c5c-9fd3-3d54f6b50862@googlegroups.com> <n2j0k4$up4$1@dont-email.me> <564dbe6b$0$1610$c3e8da3$5496439d@news.astraweb.com> <n2ki4t$aqj$1@dont-email.me> <564df258$0$1604$c3e8da3$5496439d@news.astraweb.com> <n2l0s3$5l6$1@dont-email.me> <mailman.473.1447955117.16136.python-list@python.org> <n2l3ne$hbp$1@dont-email.me> <mailman.480.1447960748.16136.python-list@python.org> <n2leck$urt$1@dont-email.me> <mailman.495.1447973754.16136.python-list@python.org> <n2lobe$7gs$1@dont-email.me> <8601c9af-a7d9-4642-ba1c-8edd1e4c3390@googlegroups.com> <56546985.8060704@rece.vub.ac.be> <CAPTjJmomomPO6ujJjZtkSXM6Eeqo8_c7i-bpad24C2zveVU0kg@mail.gmail.com> <56547337.4000709@rece.vub.ac.be> <CAPTjJmoGt3B_zTVd8dVLHNeanX=4g1yhN-PLpXzZoYiKb9HYuw@mail.gmail.com> <56547C53.8030407@rece.vub.ac.be> <CAPTjJmqAMwnxBZ97umsNg255v47dsQD6qEr0ysECtGiZ409k0Q@mail.gmail.com> <5654864E.2070906@rece.vub.ac.be> <CAPTjJmoUtwHzOEwcObh5hzUDbz-713kVE_Kq-rg_bmYFHE_tYw@mail.gmail.com> <56549324.8020607@rece.vub.ac.be>
Mime-Version: 1.0
Content-Type: text/plain; charset=UTF-8
X-Trace: news.uni-berlin.de 0lq8oZiOk6ATMiRrdFPOPQzTJLgYNCqjT7RWN94LZHYg==
Return-Path: <ian.g.kelly@gmail.com>
X-Original-To: python-list@python.org
Delivered-To: python-list@mail.python.org
X-Spam-Status: OK 0.015
X-Spam-Evidence: '*H*': 0.97; '*S*': 0.00; 'identifier,': 0.09; 'literal': 0.09; 'python:': 0.09; 'def': 0.13; '24,': 0.16; 'enumerates': 0.16; 'grounds': 0.16; 'literal,': 0.16; 'literal.': 0.16; 'literals': 0.16; 'received:io': 0.16; 'received:psf.io': 0.16; 'wrote:': 0.16; 'byte': 0.18; '2015': 0.20; 'meant': 0.22; 'constant': 0.22; 'either.': 0.22; 'produces': 0.22; 'am,': 0.23; 'import': 0.24; 'header:In-Reply-To:1': 0.24; 'chris': 0.26; 'message-id:@mail.gmail.com': 0.27; 'argue': 0.29; 'code:': 0.29; "i'm": 0.30; 'code': 0.30; 'related': 0.32; 'url:python': 0.33; 'point,': 0.33; 'though.': 0.33; 'tue,': 0.34; 'gets': 0.35; 'received:google.com': 0.35; 'nov': 0.35; 'url:org': 0.36; 'received:209.85': 0.36; 'to:addr:python-list': 0.36; 'subject:?': 0.36; 'subject:: ': 0.37; 'received:209.85.213': 0.37; 'received:209': 0.38; 'sure': 0.39; 'rather': 0.39; 'to:addr:python.org': 0.40; 'url:3': 0.60; 'is.': 0.63; 'angelico:': 0.84; 'pardon': 0.84; 'schreef': 0.84; 'to:name:python': 0.84; 'url:reference': 0.91
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :content-type; bh=m29Xj6Z8gPt+8bqLt2l55c6/+c6Wcdxfux4u0Gt8fR4=; b=pUstYmjoZVlUfJEIjTy3oV3vJ+2+0sMcQVeGYyi5m+0JfJl1zvglONyi4WclvrT1Go 9gbRzC1nUAV0goXTv+wJVxwjCTp6itKCnLjPYDX4GpOIkxF0F21X2zb6HNE5b6coIrzc zOA6pIgVWar8FMr61/AGeaZRakbbdNzlN8KDjDFkxfDlmbYpQjisPG4oVVhl8F21iHan 9qLI7ahcXSAD/a7vSqi+CmwQv2D8J4x4xhs5Up/BvcyXIbgUFJPG7MX3DwDEroU+lwD5 2A/xPEq9Aii0A58lUcZ7bkN1NXxWcSEXD5t3QkAASstA0OrUpaagkFcNw315bBbVjyC0 d1Mg==
X-Received: by 10.50.73.130 with SMTP id l2mr7265208igv.93.1448384201593; Tue, 24 Nov 2015 08:56:41 -0800 (PST)
In-Reply-To: <56549324.8020607@rece.vub.ac.be>
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>
Xref: csiph.com comp.lang.python:99368

On Tue, Nov 24, 2015 at 9:41 AM, Antoon Pardon
<antoon.pardon@rece.vub.ac.be> wrote:
> Op 24-11-15 om 16:48 schreef Chris Angelico:
>> () is not a literal either.
>
> The byte code sure suggests it is.
>
> Take the following code:
>
> import dis
>
> def f():
>   i = 42
>   t = ()
>   l = []
>
> dis.dis(f)
>
> That produces the following:
>
>
>   4           0 LOAD_CONST               1 (42)
>               3 STORE_FAST               0 (i)
>
>   5           6 LOAD_CONST               2 (())
>               9 STORE_FAST               1 (t)
>
>   6          12 BUILD_LIST               0
>              15 STORE_FAST               2 (l)
>              18 LOAD_CONST               0 (None)
>              21 RETURN_VALUE

I'm not sure what this is meant to prove. None is clearly an
identifier, not a literal, and it also gets treated as a constant in
the code above.

> So on what grounds would you argue that () is not a literal.

This enumerates exactly what literals are in Python:

https://docs.python.org/3/reference/lexical_analysis.html#literals

I think it's a rather pedantic point, though. How are nuances of the
grammar at all related to user expectations?