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Re: The binding operator, and what gets bound to what

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From Ned Batchelder <ned@nedbatchelder.com>
Subject Re: The binding operator, and what gets bound to what
Date Fri, 05 Dec 2014 07:56:26 -0500
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On 12/5/14 7:34 AM, Steven D'Aprano wrote:
> Ned Batchelder wrote:
>
>> On 12/5/14 4:53 AM, Steven D'Aprano wrote:
>>> Oh, I learned something new: strictly speaking, this is implementation-
>>> dependent and not guaranteed to work in the future!
>>>
>>> def func():
>>>       global math
>>>       import math
>>
>> I don't think this is implementation-dependent.
>
> The docs say that it is:
>
> https://docs.python.org/3/reference/simple_stmts.html#the-global-statement
>
>      Names listed in a global statement MUST NOT [emphasis added] be
>      defined as formal parameters or in a for loop control target,
>      class definition, function definition, or import statement.
>
>      CPython implementation detail: The current implementation does not
>      enforce the two restrictions, but programs should not abuse this
>      freedom, as future implementations may enforce them or silently
>      change the meaning of the program.

Ah, good.  TIL! :)

-- 
Ned Batchelder, http://nedbatchelder.com

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Thread

About Modifying Globals LJ <luisjosenovoa@gmail.com> - 2014-12-04 12:09 -0800
  Re: About Modifying Globals Chris Angelico <rosuav@gmail.com> - 2014-12-05 07:22 +1100
  Re: About Modifying Globals Ian Kelly <ian.g.kelly@gmail.com> - 2014-12-04 13:21 -0700
  Re: About Modifying Globals Dave Angel <davea@davea.name> - 2014-12-04 18:54 -0500
  Re: About Modifying Globals Chris Angelico <rosuav@gmail.com> - 2014-12-05 10:58 +1100
  Re: About Modifying Globals Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-12-05 13:09 +1100
    The binding operator, and what gets bound to what (was: About Modifying Globals) Ben Finney <ben+python@benfinney.id.au> - 2014-12-05 16:36 +1100
      Re: The binding operator, and what gets bound to what (was: About Modifying Globals) Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-12-05 20:53 +1100
        Re: The binding operator, and what gets bound to what (was: About Modifying Globals) Chris Angelico <rosuav@gmail.com> - 2014-12-05 21:03 +1100
          Re: The binding operator, and what gets bound to what (was: About Modifying Globals) Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-12-05 23:26 +1100
            Re: The binding operator, and what gets bound to what (was: About Modifying Globals) Chris Angelico <rosuav@gmail.com> - 2014-12-05 23:42 +1100
        Re: The binding operator, and what gets bound to what Ned Batchelder <ned@nedbatchelder.com> - 2014-12-05 07:06 -0500
          Re: The binding operator, and what gets bound to what Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-12-05 23:34 +1100
            Re: The binding operator, and what gets bound to what Chris Angelico <rosuav@gmail.com> - 2014-12-05 23:48 +1100
            Re: The binding operator, and what gets bound to what Ned Batchelder <ned@nedbatchelder.com> - 2014-12-05 07:56 -0500
  Re: About Modifying Globals "shiyao.ma" <i@introo.me> - 2014-12-05 10:53 +0800

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