Why there is no "setdefaultencoding" in sys module?

crow

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Jul 9, 2010, 11:58:35 AM7/9/10

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Hi, everyone

I'm a new hand at python.

I tried to set system default encoding by using

"import sys; sys.setdefaultencoding('utf-f')",

but I got error message:

>>> sys.setdefaultencoding('utf-8')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AttributeError: 'module' object has no attribute 'setdefaultencoding'

Then I checked dir(sys), seems there was no function named
"setdefaultencoding" in "sys" module. But in python's document, it
said I should use sys.setdefaultencoding.

So, my questions: why there is no setdefaultencoding in sys module? if
I want to change system's default encoding, what should I do?

Thanks in advance

Steven D'Aprano

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Jul 9, 2010, 12:04:02 PM7/9/10

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On Fri, 09 Jul 2010 08:58:35 -0700, crow wrote:

> So, my questions: why there is no setdefaultencoding in sys module? if I
> want to change system's default encoding, what should I do?

I think the answer is:

Don't.

If you do, you will break built-ins.

http://tarekziade.wordpress.com/2008/01/08/syssetdefaultencoding-is-evil/

Googling will find many discussions about this.

--
Steven

crow

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Jul 9, 2010, 12:06:41 PM7/9/10

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On Jul 10, 12:04 am, Steven D'Aprano <st...@REMOVE-THIS-

cybersource.com.au> wrote:
> On Fri, 09 Jul 2010 08:58:35 -0700, crow wrote:
> > So, my questions: why there is no setdefaultencoding in sys module? if I
> > want to change system's default encoding, what should I do?
>
> I think the answer is:
>
> Don't.
>
> If you do, you will break built-ins.
>

> http://tarekziade.wordpress.com/2008/01/08/syssetdefaultencoding-is-e...

>
> Googling will find many discussions about this.
>
> --
> Steven

Interesting, so it has been removed from python? then why it's still
in document... It's really misleading.

Thanks for your quick answer

crow

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Jul 9, 2010, 12:16:42 PM7/9/10

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oh, I take back my words, it's still there, just I need to
reload(sys).

Thomas Jollans

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Jul 9, 2010, 12:35:34 PM7/9/10

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Actually, it's still there. Lurking in the corners of sys. But site.py
knows it's evil:

% python
Python 2.6.5+ (release26-maint, Jul 6 2010, 12:58:20)
[GCC 4.4.4] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import sys
>>> sys.setdefaultencoding

Traceback (most recent call last):
File "<stdin>", line 1, in <module>
AttributeError: 'module' object has no attribute 'setdefaultencoding'

>>> reload(sys)
<module 'sys' (built-in)>
>>> sys.setdefaultencoding
<built-in function setdefaultencoding>
>>>

Christian Heimes

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Jul 9, 2010, 1:25:31 PM7/9/10

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> oh, I take back my words, it's still there, just I need to
> reload(sys).

Just don't. If you change the default encoding you are going to break
important data structures like dicts in a subtle and hard to detect way.
If your application needs to change the default encoding, it's broken.
The function is removed for a very good reaso.

Terry Reedy

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Jul 9, 2010, 5:48:30 PM7/9/10

to pytho...@python.org

On 7/9/2010 11:58 AM, crow wrote:
> But in python's document, it
> said I should use sys.setdefaultencoding.

Where? That may need to be changed.

--
Terry Jan Reedy

rajinder...@gmail.com

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Feb 15, 2018, 2:07:21 AM2/15/18

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Becuase you are using python 3.setdefaultencoding is no longer supportedin python 3. python3automatically have utf-8 in its configuration by default. so you don't have to use it. just remove the line.