Path: csiph.com!goblin1!goblin.stu.neva.ru!uio.no!news.tele.dk!news.tele.dk!small.news.tele.dk!newsgate.cistron.nl!newsgate.news.xs4all.nl!nzpost1.xs4all.net!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 0.001
X-Spam-Evidence: '*H*': 1.00; '*S*': 0.00; 'cpython': 0.05; 'indicating': 0.05; 'memory.': 0.05; 'bits': 0.07; 'defines': 0.07; 'bits.': 0.09; 'c/c++': 0.09; 'pointers': 0.09; 'received:80.91': 0.09; 'received:80.91.229': 0.09; 'received:gmane.org': 0.09; 'received:list': 0.09; 'python': 0.10; 'language,': 0.11; 'value.': 0.15; '"well,': 0.16; 'at.': 0.16; 'pointer,': 0.16; 'received:80.91.229.3': 0.16; 'received:plane.gmane.org': 0.16; 'subject:reference': 0.16; 'subject:versus': 0.16; 'wrote:': 0.16; 'integer': 0.18; 'pointer': 0.18; '>>>': 0.20; '2015': 0.20; "aren't": 0.22; 'constant': 0.22; 'object.': 0.22; 'sep': 0.22; 'programming': 0.22; 'am,': 0.23; 'sat,': 0.23; 'header:In-Reply-To:1': 0.24; 'header:User-Agent:1': 0.26; 'header:X-Complaints-To:1': 0.26; 'points': 0.27; 'arithmetic': 0.29; 'dictionary': 0.29; 'quoting': 0.29; 'objects': 0.29; "can't": 0.32; 'screen': 0.32; 'computing': 0.32; 'language.': 0.32; 'maybe': 0.33; 'point': 0.33; 'url:python': 0.33; "d'aprano": 0.33; 'steven': 0.33; 'definition': 0.34; 'editor': 0.34; 'so,': 0.35; 'text': 0.35; 'there': 0.36; 'url:org': 0.36; 'subject:" ': 0.36; 'url:library': 0.36; 'to:addr:python-list': 0.36; 'pm,': 0.36; 'subject:: ': 0.37; 'two': 0.37; 'received:org': 0.37; '12,': 0.37; 'seem': 0.37; 'data': 0.39; 'does': 0.39; 'to:addr:python.org': 0.40; 'term': 0.60; 'url:3': 0.60; 'press': 0.61; 'address': 0.61; 'black': 0.61; 'charset:windows-1252': 0.62; 'skip:n 10': 0.62; 'saturday,': 0.63; 'guaranteed': 0.67; 'address,': 0.77; 'received:12': 0.81; 'black,': 0.84; 'distinguish': 0.84; 'flipping': 0.84; 'url:functions': 0.84; 'utc+5:30,': 0.84; 'white,': 0.84
X-Injected-Via-Gmane: http://gmane.org/
To: python-list@python.org
From: Emile van Sebille <emile@fenx.com>
Subject: Re: Terminology: "reference" versus "pointer"
Date: Sat, 12 Sep 2015 10:14:05 -0700
References: <c3363$547e74fe$5419aafe$24179@news.ziggo.nl> <14afe27e-0bd5-410f-8e64-0f31d496ebf2@googlegroups.com> <b695e$55f34cad$d47876e2$41259@news.ziggo.nl> <55F36B4C.9020007@gmail.com> <1442016698.95299.381478313.2487CA0E@webmail.messagingengine.com> <mt04ao$ite$1@ger.gmane.org> <m2zj0ss2md.fsf@fastmail.com> <85mvws6z45.fsf_-_@benfinney.id.au> <mailman.404.1442032934.8327.python-list@python.org> <55f45396$0$1660$c3e8da3$5496439d@news.astraweb.com> <1dabdb08-2aee-4a53-bb57-1410edd372f6@googlegroups.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=windows-1252; format=flowed
Content-Transfer-Encoding: 7bit
X-Gmane-NNTP-Posting-Host: www.westernstatesglass.com
User-Agent: Mozilla/5.0 (Windows NT 6.2; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.2.0
In-Reply-To: <1dabdb08-2aee-4a53-bb57-1410edd372f6@googlegroups.com>
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.432.1442078061.8327.python-list@python.org>
Lines: 53
NNTP-Posting-Host: 2001:888:2000:d::a6
X-Trace: 1442078061 news.xs4all.nl 23802 [2001:888:2000:d::a6]:33197
X-Complaints-To: abuse@xs4all.nl
Xref: csiph.com comp.lang.python:96437

On 9/12/2015 9:54 AM, Rustom Mody wrote:
> On Saturday, September 12, 2015 at 10:02:40 PM UTC+5:30, Steven D'Aprano wrote:
>> On Sat, 12 Sep 2015 02:42 pm, Random832 wrote:
>>
>>> Anyway, maybe we do need a term to distinguish Python/C#/Java pointers
>>> from C/C++ pointers - maybe call it a "non-arithmetic" pointer, since
>>> the key thing about it is you can't do pointer arithmetic on them to get
>>> the object "next to" the one it points at.
>>
>> How about *just don't call them pointers*? You know, since they aren't
>> pointers in the computer science sense.
>>
>> The Free On-line Dictionary of Computing defines "pointer":
>>
>>     1. <programming> An address, from the point of view of a
>>     programming language.  A pointer may be typed, with its type
>>     indicating the type of data to which it points.
>
> <snip>
>
>> Insisting that Python has pointers is like insisting that you use a text
>> editor by flipping bits. "What happens if I press Ctrl-X?" "Well, these
>> bits on the screen flip from black to white, these bits flip from white to
>> black, and these stay the same."
>>
>
> This is from the docs
> https://docs.python.org/3/library/functions.html#id
>
> id(object)
>
>      Return the "identity" of an object. This is an integer which is guaranteed to be unique and constant for this object during its lifetime. Two objects with non-overlapping lifetimes may have the same id() value.
>
>      CPython implementation detail: This is the address of the object in memory.

Quoting from above:

 >> The Free On-line Dictionary of Computing defines "pointer":
 >>
 >>     1. <programming> An address, from the point of view of a
 >>     programming language.

So, how does the CPython program access the contents given its 'address 
in memory'?  From the definition it would seem it's not a pointer, as 
from the perspective of the programming language, you can't get there 
from the id.

Look-ma,-no-pointers-ly y'rs,

Emile