Path: csiph.com!news.swapon.de!fu-berlin.de!uni-berlin.de!not-for-mail
From: Chris Angelico <rosuav@gmail.com>
Newsgroups: comp.lang.python
Subject: Re: Assignment Versus Equality
Date: Wed, 29 Jun 2016 14:19:58 +1000
Lines: 23
Message-ID: <mailman.96.1467174006.2358.python-list@python.org>
References: <8a53c069-ca13-47bf-a24e-d2393a018b22@googlegroups.com> <nkobtu$gaq$1@dont-email.me> <l8svmbdf95jh54nmal5h3130cgmhreo3ot@4ax.com> <mailman.4.1466954526.2358.python-list@python.org> <nkotei$dk9$1@dont-email.me> <nkotv4$fif$1@dont-email.me> <nkrbgb$oc5$1@ger.gmane.org> <mailman.32.1467035992.2358.python-list@python.org> <4e72d24b-07b4-484c-83f8-a1fecc727f8c@googlegroups.com> <5773340f$0$1616$c3e8da3$5496439d@news.astraweb.com> <CAPTjJmqyR2POEe8ng6n-3-ih66JF9aXi1iq2Fhu6pxhR-7KV4w@mail.gmail.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=UTF-8
X-Trace: news.uni-berlin.de CIO+9QZ63PvamTR4/hGerwC/PSG9EaDWnUeLYZ9lPqmg==
Return-Path: <rosuav@gmail.com>
X-Original-To: python-list@python.org
Delivered-To: python-list@mail.python.org
X-Spam-Status: OK 0.016
X-Spam-Evidence: '*H*': 0.97; '*S*': 0.00; 'merging': 0.07; 'cc:addr :python-list': 0.09; 'integers': 0.09; 'runtime': 0.09; 'sane': 0.09; 'url:blog': 0.10; 'python': 0.10; 'assume': 0.11; 'wed,': 0.15; '2016': 0.16; 'from:addr:rosuav': 0.16; 'from:name:chris angelico': 0.16; 'received:io': 0.16; 'received:psf.io': 0.16; 'wrote:': 0.16; 'language': 0.19; 'cc:2**0': 0.20; 'cc:addr:python.org': 0.20; 'accuracy': 0.23; 'header:In-Reply- To:1': 0.24; 'message-id:@mail.gmail.com': 0.27; "d'aprano": 0.33; 'steven': 0.33; 'received:google.com': 0.35; 'done': 0.35; 'something': 0.35; "isn't": 0.35; 'but': 0.36; 'url:org': 0.36; 'pm,': 0.36; 'subject:: ': 0.37; 'two': 0.37; 'doing': 0.38; 'mean': 0.38; 'data': 0.39; 'does': 0.39; 'some': 0.40; 'making': 0.62; 'course': 0.62; 'great': 0.63; 'benefit': 0.66; 'worth': 0.67; 'url:10': 0.79; 'bignums,': 0.84; 'chrisa': 0.84; 'complexity': 0.84; 'to:none': 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:cc; bh=6/gbSxi3p18SFiZ/678NUm3Io2l14n8v9Yvepxpiv78=; b=ltTcvYsPsNGLfBXvucfX3G6jlUbWePIXiv8g673edQlkQerU/iy6oYghf38SvyxPlo jA/E2Jrn3xpPiy7HJNb6Ky36U7E3zbl2C27JM0bG2s6FPLi4DM4thK4aJ3PIqjkovNiU P3iC6RxkSyNWkAruDHF32zXSUaJqzWgOVxoydH0//W0BNJV9qtRDOsvcMWgPRNnr1BvP Cj/WevjGptTlW3svEGA7oSV11+Vrm7kJ92pLuelSOS5tUYlK8ROTVUTdCmjt5EKDUeku vHtTrhKojRiCB13bYuuwhAikE82JpySet5EAp1DyWisFKEFgkuxtTXezkL8u7edcgWKG 7JVw==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:cc; bh=6/gbSxi3p18SFiZ/678NUm3Io2l14n8v9Yvepxpiv78=; b=AleVNiKIHu5MJSsVQupoC8bHaDhD5Dk+2b2icC1fE5CRxdPBeN2p7WgV7s4itmj/Yj 1IjEWCpDMWDxbFhyJVXckVBO2zne9AuQSDV04CnG6nnQZtFePk6RfDDDHK5tGWUlcuIo +4g+piTGGMm+WShy74VuxV1dfCngJzDtvWvSOYkqHELXTcXbaEaGNq4wy8oGbC66sBYT fEZC0FHsTu8NLJ0JOwOnrAR99e1CBRyCBnXoKE6PUPa8qYwPQkpjJTtwMTkZDtcaPHJY ANFK+7fVKygPCO9b9hHX1ixDq8msGKxrqeIXPbBxqFRQuuHDicMARA017yt3n415MubQ phsA==
X-Gm-Message-State: ALyK8tJBBH4amPqAMbW/9f9JDqMisBeDNtYaLivihOZgy1Mo6eCO7Rop8kr2hfOXiwnJONfKPFoXEBLb38zHsg==
X-Received: by 10.194.70.41 with SMTP id j9mr6075713wju.30.1467173999662; Tue, 28 Jun 2016 21:19:59 -0700 (PDT)
In-Reply-To: <5773340f$0$1616$c3e8da3$5496439d@news.astraweb.com>
X-BeenThere: python-list@python.org
X-Mailman-Version: 2.1.22
Precedence: list
List-Id: General discussion list for the Python programming language <python-list.python.org>
List-Unsubscribe: <https://mail.python.org/mailman/options/python-list>, <mailto:python-list-request@python.org?subject=unsubscribe>
List-Archive: <http://mail.python.org/pipermail/python-list/>
List-Post: <mailto:python-list@python.org>
List-Help: <mailto:python-list-request@python.org?subject=help>
List-Subscribe: <https://mail.python.org/mailman/listinfo/python-list>, <mailto:python-list-request@python.org?subject=subscribe>
X-Mailman-Original-Message-ID: <CAPTjJmqyR2POEe8ng6n-3-ih66JF9aXi1iq2Fhu6pxhR-7KV4w@mail.gmail.com>
X-Mailman-Original-References: <8a53c069-ca13-47bf-a24e-d2393a018b22@googlegroups.com> <nkobtu$gaq$1@dont-email.me> <l8svmbdf95jh54nmal5h3130cgmhreo3ot@4ax.com> <mailman.4.1466954526.2358.python-list@python.org> <nkotei$dk9$1@dont-email.me> <nkotv4$fif$1@dont-email.me> <nkrbgb$oc5$1@ger.gmane.org> <mailman.32.1467035992.2358.python-list@python.org> <4e72d24b-07b4-484c-83f8-a1fecc727f8c@googlegroups.com> <5773340f$0$1616$c3e8da3$5496439d@news.astraweb.com>
Xref: csiph.com comp.lang.python:110746

On Wed, Jun 29, 2016 at 12:35 PM, Steven D'Aprano <steve@pearwood.info> wrote:
>
> Whereas some decisions are just dumb:
>
> https://www.jwz.org/blog/2010/10/every-day-i-learn-something-new-and-stupid/

"""It would also be reasonable to assume that any sane language
runtime would have integers transparently degrade to BIGNUMs, making
the choice of accuracy over speed, but of course that almost never
happens..."""

Python 2 did this, but Python 3 doesn't. Does this mean that:

1) The performance advantage of native integers is negligible?
2) The performance benefit of having two representations for integers
isn't worth the complexity of one data type having two
representations?
3) The advantage of merging the types was so great that it was done in
the most straight-forward way, and then nobody got around to doing
performance testing?
4) Something else?

ChrisA