Re: When do default parameters get their values set?

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From	Terry Reedy <tjreedy@udel.edu>
Subject	Re: When do default parameters get their values set?
Date	Mon, 08 Dec 2014 20:37:58 -0500
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Show key headers only | View raw

 >>> def f(a="default "+"arg value"): return a

 >>> f.__defaults__
('default arg value',)

Before any calls, the expression has be evaluated.  When f() is called 
with no arg, the local name 'a' is associated with
'default arg value'. Then code execution begins. Use dir(f), for 
instance, to invesigate internals.

-- 
Terry Jan Reedy

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Thread

When do default parameters get their values set? bSneddon <w.g.sneddon@gmail.com> - 2014-12-08 14:10 -0800
  Re: When do default parameters get their values set? Chris Angelico <rosuav@gmail.com> - 2014-12-09 09:28 +1100
  Re: When do default parameters get their values set? Chris Kaynor <ckaynor@zindagigames.com> - 2014-12-08 14:28 -0800
  Re: When do default parameters get their values set? Dave Angel <davea@davea.name> - 2014-12-08 17:30 -0500
  Re: When do default parameters get their values set? Tim Chase <python.list@tim.thechases.com> - 2014-12-08 16:26 -0600
  Re: When do default parameters get their values set? bSneddon <w.g.sneddon@gmail.com> - 2014-12-08 15:35 -0800
  Re: When do default parameters get their values set? Terry Reedy <tjreedy@udel.edu> - 2014-12-08 20:37 -0500

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