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Re: Question about name scope

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Dave Angel wrote:

> I tried your experiment using Python 2.7 and Linux 11.04
> 
> 
> def f(a):
>      from math import sin, cos
>      return sin(a) + cos(a)
> 
> print f(45)
> 
> Does what you needed, and neatly.  The only name added to the global
> namspace is f, of type function.
> 
> I was a bit surprised that using   from math import * inside the
> function worked, but it generates  a warning:
> olive.py:2: SyntaxWarning: import * only allowed at module level
>    def f(a):

I guess they want local symbols in functions to be pre-compiled.  Similar to 
the way you can't usefully update the dict returned by locals().  Strangely, 
I notice that

Python 2.6.5 (r265:79063, Apr 16 2010, 13:09:56) 
[GCC 4.4.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> def f(x):
...   exec x
...   exec 'print a'
... 
>>> f('a=4')
4
>>> 

works, but I really cannot explain why.

	Mel.

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Thread

Question about name scope Olive <diolu@bigfoot.com> - 2012-02-01 18:11 +0100
  Re: Question about name scope Rick Johnson <rantingrickjohnson@gmail.com> - 2012-02-01 09:21 -0800
  Re: Question about name scope Ethan Furman <ethan@stoneleaf.us> - 2012-02-01 09:43 -0800
  Re: Question about name scope Dave Angel <d@davea.name> - 2012-02-01 12:36 -0500
    Re: Question about name scope Mel Wilson <mwilson@the-wire.com> - 2012-02-01 13:47 -0500
      Re: Question about name scope Ian Kelly <ian.g.kelly@gmail.com> - 2012-02-01 14:49 -0700
      Re: Question about name scope Ian Kelly <ian.g.kelly@gmail.com> - 2012-02-01 15:38 -0700
      Re: Question about name scope Ethan Furman <ethan@stoneleaf.us> - 2012-02-01 14:24 -0800
      Re: Question about name scope Ian Kelly <ian.g.kelly@gmail.com> - 2012-02-01 16:00 -0700
      Re: Question about name scope Ethan Furman <ethan@stoneleaf.us> - 2012-02-01 15:08 -0800
      Re: Question about name scope Ian Kelly <ian.g.kelly@gmail.com> - 2012-02-01 16:47 -0700
      Re: Question about name scope Ethan Furman <ethan@stoneleaf.us> - 2012-02-01 14:53 -0800
        Re: Question about name scope Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-02-02 00:34 +0000
      Re: Question about name scope Ethan Furman <ethan@stoneleaf.us> - 2012-02-01 15:59 -0800
      Re: Question about name scope Ethan Furman <ethan@stoneleaf.us> - 2012-02-01 15:41 -0800
      Re: Question about name scope Ethan Furman <ethan@stoneleaf.us> - 2012-02-01 15:51 -0800
  Re: Question about name scope Chris Rebert <clp2@rebertia.com> - 2012-02-01 09:38 -0800
  Re: Question about name scope Christian Heimes <lists@cheimes.de> - 2012-02-01 18:50 +0100

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