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

Groups > comp.lang.python > #67520 > unrolled thread

Reference

Back to article view | Back to comp.lang.python

Contents

  Reference "ast" <nomail@invalid.com> - 2014-03-03 10:42 +0100
    Object identity (was: Reference) Ben Finney <ben+python@benfinney.id.au> - 2014-03-03 21:00 +1100
      Re: Object identity (was: Reference) "ast" <nomail@invalid.com> - 2014-03-03 11:21 +0100
    Re: Reference "Mark H. Harris" <harrismh777@gmail.com> - 2014-03-03 05:09 -0800
    Re: Reference Grant Edwards <invalid@invalid.invalid> - 2014-03-03 14:29 +0000
    Re: Reference Rustom Mody <rustompmody@gmail.com> - 2014-03-03 07:52 -0800
      Re: Reference Ben Finney <ben+python@benfinney.id.au> - 2014-03-04 08:10 +1100
      Re: Reference Tim Chase <python.list@tim.thechases.com> - 2014-03-03 15:24 -0600
      Re: Reference Ben Finney <ben+python@benfinney.id.au> - 2014-03-04 08:31 +1100
      Re: Reference Mark Lawrence <breamoreboy@yahoo.co.uk> - 2014-03-03 21:35 +0000
        Re: Reference Marko Rauhamaa <marko@pacujo.net> - 2014-03-04 00:07 +0200
          Re: Reference Ben Finney <ben+python@benfinney.id.au> - 2014-03-04 09:18 +1100
            Re: Reference Alister <alister.ware@ntlworld.com> - 2014-03-04 11:10 +0000
              Re: Reference Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-03-04 11:48 +0000
                Re: Reference "Rhodri James" <rhodri@wildebst.org.uk> - 2014-03-05 00:25 +0000
      Re: Reference Tim Chase <python.list@tim.thechases.com> - 2014-03-03 15:51 -0600
      Re: Reference Jerry Hill <malaclypse2@gmail.com> - 2014-03-03 17:02 -0500
        Re: Reference Marko Rauhamaa <marko@pacujo.net> - 2014-03-04 00:22 +0200
          Re: Reference Chris Angelico <rosuav@gmail.com> - 2014-03-04 09:27 +1100
          Re: Reference Ben Finney <ben+python@benfinney.id.au> - 2014-03-04 09:33 +1100
          Re: Reference Steven D'Aprano <steve@pearwood.info> - 2014-03-04 04:52 +0000
            Re: Reference Chris Angelico <rosuav@gmail.com> - 2014-03-04 16:24 +1100
              Re: Reference "Rhodri James" <rhodri@wildebst.org.uk> - 2014-03-05 01:08 +0000
                Re: Reference Roy Smith <roy@panix.com> - 2014-03-04 21:09 -0500
                  Re: Reference Rustom Mody <rustompmody@gmail.com> - 2014-03-04 19:36 -0800
                    Re: Reference Ian Kelly <ian.g.kelly@gmail.com> - 2014-03-04 21:08 -0700
                      Re: Reference Rustom Mody <rustompmody@gmail.com> - 2014-03-04 20:31 -0800
                    Re: Reference Ben Finney <ben+python@benfinney.id.au> - 2014-03-05 15:32 +1100
                      Re: Reference Rustom Mody <rustompmody@gmail.com> - 2014-03-04 20:47 -0800
                    Re: Reference Steven D'Aprano <steve@pearwood.info> - 2014-03-05 05:06 +0000
                      Re: Reference Rustom Mody <rustompmody@gmail.com> - 2014-03-04 21:47 -0800
                        Re: Reference alex23 <wuwei23@gmail.com> - 2014-03-05 16:01 +1000
                          Re: Reference Rustom Mody <rustompmody@gmail.com> - 2014-03-04 22:10 -0800
                            Re: Reference Ben Finney <ben+python@benfinney.id.au> - 2014-03-05 17:22 +1100
                            Re: Reference alex23 <wuwei23@gmail.com> - 2014-03-05 16:28 +1000
                              Re: Reference Mark Lawrence <breamoreboy@yahoo.co.uk> - 2014-03-05 12:24 +0000
                            Re: Reference Mark Lawrence <breamoreboy@yahoo.co.uk> - 2014-03-05 12:21 +0000
                        Re: Reference Ben Finney <ben+python@benfinney.id.au> - 2014-03-05 17:20 +1100
                          Re: Reference Rustom Mody <rustompmody@gmail.com> - 2014-03-05 09:40 -0800
                            Re: Reference Tim Chase <python.list@tim.thechases.com> - 2014-03-05 12:12 -0600
                            Re: Reference Ben Finney <ben+python@benfinney.id.au> - 2014-03-06 05:33 +1100
                        Re: Reference Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-03-05 18:19 +0000
                          Re: Reference Marko Rauhamaa <marko@pacujo.net> - 2014-03-05 22:23 +0200
                            Re: Reference Grant Edwards <invalid@invalid.invalid> - 2014-03-05 20:31 +0000
                              Re: Reference Marko Rauhamaa <marko@pacujo.net> - 2014-03-05 22:46 +0200
                                Re: Reference Ben Finney <ben+python@benfinney.id.au> - 2014-03-06 08:07 +1100
                                Re: Reference Ben Finney <ben+python@benfinney.id.au> - 2014-03-06 08:10 +1100
                                Re: Reference Mark Lawrence <breamoreboy@yahoo.co.uk> - 2014-03-05 21:34 +0000
                                Re: Reference Terry Reedy <tjreedy@udel.edu> - 2014-03-05 18:00 -0500
                            Re: Reference Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-03-06 03:01 +0000
                      Re: Reference Rustom Mody <rustompmody@gmail.com> - 2014-03-04 22:03 -0800
                        Re: Reference Ben Finney <ben+python@benfinney.id.au> - 2014-03-05 17:26 +1100
                        Re: Reference Chris Angelico <rosuav@gmail.com> - 2014-03-05 17:32 +1100
                        Re: Reference Tim Chase <python.list@tim.thechases.com> - 2014-03-05 08:24 -0600
                        Re: Reference Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-03-05 18:29 +0000
                          Re: Reference Marko Rauhamaa <marko@pacujo.net> - 2014-03-05 22:34 +0200
                            Re: Reference Ben Finney <ben+python@benfinney.id.au> - 2014-03-06 08:01 +1100
                              Re: Reference Marko Rauhamaa <marko@pacujo.net> - 2014-03-05 23:14 +0200
                                Re: Reference Chris Angelico <rosuav@gmail.com> - 2014-03-06 08:26 +1100
                                  Re: Reference Marko Rauhamaa <marko@pacujo.net> - 2014-03-05 23:50 +0200
                                  Re: Reference Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-03-06 00:35 +0000
                                    Re: Reference Chris Angelico <rosuav@gmail.com> - 2014-03-06 11:50 +1100
                                    Re: Reference Mark Lawrence <breamoreboy@yahoo.co.uk> - 2014-03-06 17:46 +0000
                                Re: Reference Tim Chase <python.list@tim.thechases.com> - 2014-03-05 15:33 -0600
                                Re: Reference Ben Finney <ben+python@benfinney.id.au> - 2014-03-06 08:37 +1100
                                  Re: Reference Marko Rauhamaa <marko@pacujo.net> - 2014-03-06 02:52 +0200
                                    Re: Reference Ben Finney <ben+python@benfinney.id.au> - 2014-03-06 12:05 +1100
                                    Re: Reference alex23 <wuwei23@gmail.com> - 2014-03-06 12:12 +1000
                                Re: Reference Mark Lawrence <breamoreboy@yahoo.co.uk> - 2014-03-05 21:46 +0000
                    Re: Reference Marko Rauhamaa <marko@pacujo.net> - 2014-03-05 08:23 +0200
                      Re: Reference Rustom Mody <rustompmody@gmail.com> - 2014-03-04 22:33 -0800
                        Re: Reference Ben Finney <ben+python@benfinney.id.au> - 2014-03-05 17:40 +1100
                      Re: Reference Mark Lawrence <breamoreboy@yahoo.co.uk> - 2014-03-05 12:35 +0000
                      Re: Reference Chris Angelico <rosuav@gmail.com> - 2014-03-05 23:45 +1100
            Re: Reference Jerry Hill <malaclypse2@gmail.com> - 2014-03-04 10:19 -0500
              Re: Reference Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-03-04 15:42 +0000
                Re: Reference Chris Angelico <rosuav@gmail.com> - 2014-03-05 03:02 +1100
                  Re: Reference Roy Smith <roy@panix.com> - 2014-03-04 11:14 -0500
                Re: Reference MRAB <python@mrabarnett.plus.com> - 2014-03-04 17:12 +0000
              Re: Reference Rustom Mody <rustompmody@gmail.com> - 2014-03-04 08:24 -0800
            Re: Reference Chris Angelico <rosuav@gmail.com> - 2014-03-05 02:25 +1100
            Re: Reference Antoon Pardon <antoon.pardon@rece.vub.ac.be> - 2014-03-05 14:37 +0100
        Re: Reference Steven D'Aprano <steve@pearwood.info> - 2014-03-04 03:59 +0000
      Re: Reference Ben Finney <ben+python@benfinney.id.au> - 2014-03-04 09:17 +1100
        Re: Reference Roy Smith <roy@panix.com> - 2014-03-03 18:02 -0500
          Re: Reference Chris Angelico <rosuav@gmail.com> - 2014-03-04 10:09 +1100
          Re: Reference Steven D'Aprano <steve@pearwood.info> - 2014-03-04 04:38 +0000
    Re: Reference Terry Reedy <tjreedy@udel.edu> - 2014-03-03 13:48 -0500
      Re: Reference Steven D'Aprano <steve@pearwood.info> - 2014-03-04 03:45 +0000
      Re: Reference Alexander Blinne <news@blinne.net> - 2014-03-04 13:55 +0100
        Re: Reference Chris Angelico <rosuav@gmail.com> - 2014-03-05 01:06 +1100
          Re: Reference Alexander Blinne <news@blinne.net> - 2014-03-04 22:53 +0100
            Re: Reference Chris Angelico <rosuav@gmail.com> - 2014-03-05 09:01 +1100

Page 1 of 5  [1] 2 3 4 5  Next page →

#67520 — Reference

hello

Consider following code:

>>> A=7
>>> B=7
>>> A is B
True

I understand that there is a single object 7 somewhere in memory and
both variables A and B point toward this object 7

now do the same with a list:

>>> l1 = [1, 2]
>>> l2 = [1, 2]
>>> l1 is l2
False

It seems this time that there are 2 distincts objects [1, 2] in memory. l1 points
toward the first one and l2 points toward the second one.

if I change one, the second remains unchanged

>>> l1.append(3)
>>> l1
[1, 2, 3]
>>> l2
[1, 2]

I dont really understand why the behavior is different. 
Both integer 7 and list [1, 2] are objects. Why is it
different ?

thanks

[toc] | [next] | [standalone]

#67522 — Object identity (was: Reference)

"ast" <nomail@invalid.com> writes:

> >>> A=7
> >>> B=7
> >>> A is B
> True
>
> I understand that there is a single object 7 somewhere in memory and
> both variables A and B point toward this object 7

Try not to think in terms of “point to”. Rather, the names “A” and “B”
are bound to that object.

The distinction is subtle; but it's important to realise that *all*
references in Python do this, and there's no way to talk about an object
in Python without using a reference. The “pointer” model from other
languages doesn't exist in Python.

> now do the same with a list:
>
> >>> l1 = [1, 2]
> >>> l2 = [1, 2]
> >>> l1 is l2
> False
>
> It seems this time that there are 2 distincts objects [1, 2] in
> memory.

That's correct.

> I dont really understand why the behavior is different. Both integer 7
> and list [1, 2] are objects. Why is it different ?

Short answer: object identity is an implementation detail.

It's up to the Python implementation to decide when to re-use an object
when a new one is requested. No guarantee is made, when you ask to
create an object, that you won't get an existing one if that would work
just as well.

Since the integer object 7 is immutable, it will behave the same no
matter how many times you ask for a new one, the Python implementation
can choose to give you the same object. But it might not — don't depend
on this!

Since two separate lists are mutable, each one can have a distinct
history after creation, so it would be less helpful to return an
existing list when you ask for a new one. But again, there's no
guarantee here either! A Python implementation might decide to give you
an existing list, if existing guarantees can be kept.

The moral is: Don't depend on differences in object identity. You can be
guaranteed that an object will retain its own identity, and its identity
will always be different from all other co-existing objects that have
different values. Beyond that, don't make any assumptions.

-- 
 \              “Programs must be written for people to read, and only |
  `\        incidentally for machines to execute.” —Abelson & Sussman, |
_o__)              _Structure and Interpretation of Computer Programs_ |
Ben Finney

[toc] | [prev] | [next] | [standalone]

#67524 — Re: Object identity (was: Reference)

thanks ben, that's clear

[toc] | [prev] | [next] | [standalone]

#67538

On Monday, March 3, 2014 3:42:30 AM UTC-6, ast wrote:

> Consider following code:
> 
> >>> A=7
> >>> B=7
> >>> A is B
> True

The names A and B are both bound to the same object (7). 
You will discover that this is True for all small ints less
than 257;  on CPython3.3.4.  I just checked it.   :)

Its just more efficient to do this for small ints because they 
are immutable (1) and because they are used for frequently (2).

As somebody pointed out last week, don't use "is" for ints and 
strings (generally speaking). Value is what's important here,
not identity. My python coding is yet simple and straight
forward enough that I have not had a need yet for "is". 

Cheers
marcus

[toc] | [prev] | [next] | [standalone]

#67555

On 2014-03-03, ast <nomail@invalid.com> wrote:
> hello
>
> Consider following code:
>
>>>> A=7
>>>> B=7
>>>> A is B
> True
>
> I understand that there is a single object 7 somewhere in memory

Maybe, maybe not.  Integer are immutable, so that's allowed but not
required. In CPython, that's true for small integers, but that is an
implementation detail, and you shouldn't depend on it.

> and both variables A and B point toward this object 7

They might.  They might not.

> now do the same with a list:
>
>>>> l1 = [1, 2]
>>>> l2 = [1, 2]
>>>> l1 is l2
> False
>
> It seems this time that there are 2 distincts objects [1, 2] in
> memory.

Yep.  Lists are mutable, therefore each literal produces a distinct
object.

> l1 points toward the first one and l2 points toward the
> second one.

Yep.

> I dont really understand why the behavior is different. 
> Both integer 7 and list [1, 2] are objects. Why is it
> different ?

Integer objects are immutable (they can't change value), therefore you
can reuse them without causing problems.  Lists are mutable (you can
change the values in them), so you can't reuse them.

-- 
Grant Edwards               grant.b.edwards        Yow! Maybe I should have
                                  at               asked for my Neutron Bomb
                              gmail.com            in PAISLEY --

[toc] | [prev] | [next] | [standalone]

#67561

On Monday, March 3, 2014 3:12:30 PM UTC+5:30, ast wrote:
> hello

> Consider following code:

> >>> A=7
> >>> B=7
> >>> A is B
> True

> I understand that there is a single object 7 somewhere in memory and
> both variables A and B point toward this object 7

> now do the same with a list:

> >>> l1 = [1, 2]
> >>> l2 = [1, 2]
> >>> l1 is l2
> False

> It seems this time that there are 2 distincts objects [1, 2] in memory. l1 points
> toward the first one and l2 points toward the second one.

> if I change one, the second remains unchanged

> >>> l1.append(3)
> >>> l1
> [1, 2, 3]
> >>> l2
> [1, 2]

> I dont really understand why the behavior is different. 
> Both integer 7 and list [1, 2] are objects. Why is it
> different ?

Short answer: Avoid using 'is'. 

Long answer: http://www.beyondwilber.ca/healing-thinking/non-identity-korzybski.html

Pragmatic answer: Think of 'is' as a short-form for 'machine-rep-is'
And use machine representations with the same alacrity that a
C programmer uses inline assembly

[toc] | [prev] | [next] | [standalone]

#67581

Rustom Mody <rustompmody@gmail.com> writes:

> Short answer: Avoid using 'is'. 

This is bad advice in a Python forum.

The ‘is’ operator is commonly used in Python, so please don't advise
against it in an unqualified “short answer”.

> Long answer: http://www.beyondwilber.ca/healing-thinking/non-identity-korzybski.html

Interesting, but mostly a distraction for the querent here.

Short answer: Use ‘use’ any time you need to compare object identity.
You usually do not need to compare object identity.

-- 
 \        “Some people, when confronted with a problem, think ‘I know, |
  `\       I'll use regular expressions’. Now they have two problems.” |
_o__)                           —Jamie Zawinski, in alt.religion.emacs |
Ben Finney

[toc] | [prev] | [next] | [standalone]

#67584

On 2014-03-04 08:10, Ben Finney wrote:
> > Long answer:
> > http://www.beyondwilber.ca/healing-thinking/non-identity-korzybski.html  
> 
> Interesting, but mostly a distraction for the querent here.
> 
> Short answer: Use ‘use’ any time you need to compare object
> identity. You usually do not need to compare object identity.

I think there use something wrong with that sentence...unless there
usen't. ;-)

-tkc

[toc] | [prev] | [next] | [standalone]

#67585

Tim Chase <python.list@tim.thechases.com> writes:

> On 2014-03-04 08:10, Ben Finney wrote:
> > Short answer: Use ‘use’ any time you need to compare object
> > identity. You usually do not need to compare object identity.

Damn it, a snappy response marred by a typo.

> I think there use something wrong with that sentence...unless there
> usen't. ;-)

That use correct. Thanks, Tim :-)

-- 
 \      “Software patents provide one more means of controlling access |
  `\      to information. They are the tool of choice for the internet |
_o__)                                     highwayman.” —Anthony Taylor |
Ben Finney

[toc] | [prev] | [next] | [standalone]

#67587

On 03/03/2014 21:10, Ben Finney wrote:
> Rustom Mody <rustompmody@gmail.com> writes:
>
>> Short answer: Avoid using 'is'.
>
> This is bad advice in a Python forum.
>
> The ‘is’ operator is commonly used in Python, so please don't advise
> against it in an unqualified “short answer”.
>
>> Long answer: http://www.beyondwilber.ca/healing-thinking/non-identity-korzybski.html
>
> Interesting, but mostly a distraction for the querent here.
>
> Short answer: Use ‘use’ any time you need to compare object identity.
> You usually do not need to compare object identity.
>

That last paragraph is as clear as mud.

I'd just like to know why people are so obsessed with identities, I've 
never thought to use them in 10+ years of writing Python.  Do I use the 
KISS principle too often?

-- 
My fellow Pythonistas, ask not what our language can do for you, ask 
what you can do for our language.

Mark Lawrence

---
This email is free from viruses and malware because avast! Antivirus protection is active.
http://www.avast.com

[toc] | [prev] | [next] | [standalone]

#67595

Mark Lawrence <breamoreboy@yahoo.co.uk>:

> I'd just like to know why people are so obsessed with identities, I've
> never thought to use them in 10+ years of writing Python.  Do I use the
> KISS principle too often?

Calmly choosing the right tool for the job is not an obsession.


Marko

[toc] | [prev] | [next] | [standalone]

#67602

Marko Rauhamaa <marko@pacujo.net> writes:

> Mark Lawrence <breamoreboy@yahoo.co.uk>:
>
> > I'd just like to know why people are so obsessed with identities, I've
> > never thought to use them in 10+ years of writing Python.  Do I use the
> > KISS principle too often?
>
> Calmly choosing the right tool for the job is not an obsession.

Persistently banging your head in contradiction to the facts of Python's
data model, as you have been doing, starts to look very much like
obsession.

-- 
 \                “Please to bathe inside the tub.” —hotel room, Japan |
  `\                                                                   |
_o__)                                                                  |
Ben Finney

[toc] | [prev] | [next] | [standalone]

#67661

On Tue, 04 Mar 2014 09:18:57 +1100, Ben Finney wrote:

> Marko Rauhamaa <marko@pacujo.net> writes:
> 
>> Mark Lawrence <breamoreboy@yahoo.co.uk>:
>>
>> > I'd just like to know why people are so obsessed with identities,
>> > I've never thought to use them in 10+ years of writing Python.  Do I
>> > use the KISS principle too often?
>>
>> Calmly choosing the right tool for the job is not an obsession.
> 
> Persistently banging your head in contradiction to the facts of Python's
> data model, as you have been doing, starts to look very much like
> obsession.

Definition of insanity

Doing the same thing over and over again & expecting different results



-- 
Support staff hung over, send aspirin and come back LATER.

[toc] | [prev] | [next] | [standalone]

#67665

On Tue, 04 Mar 2014 11:10:34 +0000, Alister wrote:

> Definition of insanity
> 
> Doing the same thing over and over again & expecting different results

*rolls dice*


:-)



-- 
Steven D'Aprano
http://import-that.dreamwidth.org/

[toc] | [prev] | [next] | [standalone]

#67765

On Tue, 04 Mar 2014 11:48:46 -0000, Steven D'Aprano  
<steve+comp.lang.python@pearwood.info> wrote:

> On Tue, 04 Mar 2014 11:10:34 +0000, Alister wrote:
>
>> Definition of insanity
>>
>> Doing the same thing over and over again & expecting different results
>
> *rolls dice*

As any gamer will tell you, dice are not random number generators.  They  
are far too cussed for that :-)


-- 
Rhodri James *-* Wildebeest Herder to the Masses

[toc] | [prev] | [next] | [standalone]

#67591

On 2014-03-03 21:35, Mark Lawrence wrote:
> I'd just like to know why people are so obsessed with identities,
> I've never thought to use them in 10+ years of writing Python.  Do
> I use the KISS principle too often?

There are a couple use-cases I've encountered where "is" matters:

1) the most popular:

  if foo is None:
    do_stuff()

2) sentinels (which are effectively non-None None values)

  SENTINEL = object()

  def myfuntion(value=SENTINEL):
    if value is SENTINEL:
      do_something_parameterless()
    else:
      do_something_else(value) # allow for value=None

3) when doing recursion and you want to prevent touching the same
object multiple times, such as what happens when you do

  lst = [1,2,3]
  lst.append(lst)
  print(lst)

and it needs to recognize that the final element of "lst" is one that
it has already seen (as done by identity).


There might be some other use cases, but #1 is a good 95% of my
usage, #2 is a good 4%, and I can only think of once in my Python
career when I've needed to do what is described in #3.

-tkc

[toc] | [prev] | [next] | [standalone]

#67593

On Mon, Mar 3, 2014 at 4:51 PM, Tim Chase <python.list@tim.thechases.com> wrote:
> There are a couple use-cases I've encountered where "is" matters:
>
> 1) the most popular:
>
>   if foo is None:
>     do_stuff()

I know this is the one that always comes up, but honestly, I feel like
"is" doesn't matter here.  That code would be just as correct if it
was written as:

if foo == None:
    do_stuff()

The only time it would give you a different result from the "is"
version is if foo was bound to an object that returned True when
compared with None.  And if that were the case, I'm still not
convinced that you can tell from looking at those two lines of code
which one is buggy, except for the fact that there has been 20 years
of custom saying that comparing to None with equality is wrong.

-- 
Jerry

[toc] | [prev] | [next] | [standalone]

#67603

Jerry Hill <malaclypse2@gmail.com>:

> except for the fact that there has been 20 years of custom saying that
> comparing to None with equality is wrong.

"if foo == None" is not wrong in any manner. It's just that if you are
comfortable with the "is" operator and its semantics, "if foo is None"
is slightly more natural.

You generally use "==" if more than one object could be equal. If you
know there's only one object of the kind, you convey that knowledge by
the use of "is" even when functionally, it doesn't matter.


Marko

[toc] | [prev] | [next] | [standalone]

#67604

On Tue, Mar 4, 2014 at 9:22 AM, Marko Rauhamaa <marko@pacujo.net> wrote:
> You generally use "==" if more than one object could be equal. If you
> know there's only one object of the kind, you convey that knowledge by
> the use of "is" even when functionally, it doesn't matter.

It's even simpler than that.

You use "==" when you care about value, and "is" when you care about identity.

This is because "==" tests value, and "is" tests identity.

I do not understand why there is confusion.

ChrisA

[toc] | [prev] | [next] | [standalone]

#67607

Marko Rauhamaa <marko@pacujo.net> writes:

> Jerry Hill <malaclypse2@gmail.com>:
>
> > except for the fact that there has been 20 years of custom saying that
> > comparing to None with equality is wrong.
>
> "if foo == None" is not wrong in any manner.

Marko, please don't keep asserting falsehoods. It's already been pointed
out in this forum many times, essentially since the forum existed, why
what you say here is false.

-- 
 \          “The fact that I have no remedy for all the sorrows of the |
  `\     world is no reason for my accepting yours. It simply supports |
_o__)  the strong probability that yours is a fake.” —Henry L. Mencken |
Ben Finney

[toc] | [prev] | [next] | [standalone]

Page 1 of 5  [1] 2 3 4 5  Next page →

Back to top | Article view | comp.lang.python

csiph-web