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From: Terry Reedy <tjreedy@udel.edu>
Newsgroups: comp.lang.python
Subject: Re: static variables
Date: Mon, 30 Nov 2015 12:38:40 -0500
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On 11/30/2015 12:15 PM, Ulli Horlacher wrote:
>
> I try to to implement a "static variable" inside a function:
>
> def main():
>    a(1)
>    a(2)
>    a()
>    print(a.x)
>    if 'a.x' in globals(): print('global variable')
>    if 'a.x' in locals():  print('local variable')
>
> def a(x=None):
>    if not x is None: a.x = x
>    print(':',a.x)
>
> main()
>
> When I run this code, I get:
>
> : 1
> : 2
> : 2
> 2
>
> This is exactly what I expect.
> But what is a.x?
> It is neither a variable in globals() nor in locals()

a.x is an attribute of the object a.


-- 
Terry Jan Reedy