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Re: When do default parameters get their values set?

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Subject Re: When do default parameters get their values set?
Date Tue, 09 Dec 2014 18:07:53 -0500
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On Tue, Dec 9, 2014, at 16:18, Duncan Booth wrote:
> The default parameters are actually evaluated when the 'def' statement is 
> executed and the function object is created from the default arguments
> and 
> the previously compiled code block.

Which means that if you execute the def statement [or lambda] more than
once, you will get more than one instance of the default parameter.

>>> def f(): return (lambda x={}: x)
...
>>> f()() is f()()
False
>>> g = f()
>>> g() is g()
True

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Thread

When do default parameters get their values set? "bSneddon" <bsneddon@1:249/999.remove-cdt-this> - 2014-12-09 11:32 -0500
  Re: When do default parameters get their values set? "Chris Angelico" <chris.angelico@1:249/999.remove-cdt-this> - 2014-12-09 11:32 -0500
  Re: When do default parameters get their values set? "Dave Angel" <dave.angel@1:249/999.remove-cdt-this> - 2014-12-09 11:32 -0500
    Re: When do default parameters get their values set? Duncan Booth <duncan.booth@invalid.invalid> - 2014-12-09 21:18 +0000
      Re: When do default parameters get their values set? random832@fastmail.us - 2014-12-09 18:07 -0500
        Re: When do default parameters get their values set? Rustom Mody <rustompmody@gmail.com> - 2014-12-09 18:44 -0800
          Re: When do default parameters get their values set? random832@fastmail.us - 2014-12-10 13:38 -0500
            Re: When do default parameters get their values set? Rustom Mody <rustompmody@gmail.com> - 2014-12-10 18:18 -0800
              Re: When do default parameters get their values set? Chris Angelico <rosuav@gmail.com> - 2014-12-11 13:24 +1100
                Re: When do default parameters get their values set? Rustom Mody <rustompmody@gmail.com> - 2014-12-10 18:50 -0800
              Re: When do default parameters get their values set? Steven D'Aprano <steve@pearwood.info> - 2014-12-11 03:15 +0000
                Re: When do default parameters get their values set? Rustom Mody <rustompmody@gmail.com> - 2014-12-10 19:26 -0800
                Re: When do default parameters get their values set? Ben Finney <ben+python@benfinney.id.au> - 2014-12-11 14:49 +1100
                Re: When do default parameters get their values set? Chris Kaynor <ckaynor@zindagigames.com> - 2014-12-11 09:10 -0800
                Re: When do default parameters get their values set? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-12-12 09:51 +1100
              Re: When do default parameters get their values set? random832@fastmail.us - 2014-12-11 15:44 -0500
  Re: When do default parameters get their values set? "Tim Chase" <tim.chase@1:249/999.remove-cdt-this> - 2014-12-09 11:32 -0500

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