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Re: Question about Pass-by-object-reference?

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On 07/22/2014 04:00 PM, fl wrote:
> On Tuesday, July 22, 2014 4:35:33 PM UTC-4, Peter Pearson wrote:
>> On Tue, 22 Jul 2014 12:34:51 -0700 (PDT), fl <r@gmail.com> wrote:
>> When you say "def reassign(list)", that means "I'm defining a function
>> to which the caller will pass one object, and within this function I'm
>> going to refer to that object by the name 'list'."
>>
>>
>>
>> Then, when you say "list=[0,1]", that means "Create the object [0,1],
>
> The above is what rebind? see below I cite.

exactly.  assigning to a variable within a function makes that variable 
local to the function; assigning to the contents (as with [:]) changes 
the contents, but not the container variable, and as the container 
element was passed in you'll see the changed item outside the function.

Emile



>
>> and assign to it the name 'list'."  At this point, there is no longer
>> any name that refers to the object that the caller passed.
>
> Here is I find on-line about "Arguments are passed by assignment."
> http://stackoverflow.com/questions/986006/python-how-do-i-pass-a-variable-by-reference
>
> "If you pass a mutable object into a method, the method gets a reference to that
> same object and you can mutate it to your heart's delight, but if you rebind the
> reference in the method, the outer scope will know nothing about it, and after
> you're done, the outer reference will still point at the original object."
>
> Thanks
>

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Question about Pass-by-object-reference? fl <rxjwg98@gmail.com> - 2014-07-22 12:04 -0700
  Re: Question about Pass-by-object-reference? Ned Batchelder <ned@nedbatchelder.com> - 2014-07-22 15:32 -0400
    Re: Question about Pass-by-object-reference? fl <rxjwg98@gmail.com> - 2014-07-22 12:54 -0700
  Re: Question about Pass-by-object-reference? fl <rxjwg98@gmail.com> - 2014-07-22 12:34 -0700
    Re: Question about Pass-by-object-reference? Peter Pearson <ppearson@nowhere.invalid> - 2014-07-22 20:35 +0000
      Re: Question about Pass-by-object-reference? emile <emile@fenx.com> - 2014-07-22 13:46 -0700
        Re: Question about Pass-by-object-reference? fl <rxjwg98@gmail.com> - 2014-07-22 15:17 -0700
          Re: Question about Pass-by-object-reference? Joel Goldstick <joel.goldstick@gmail.com> - 2014-07-22 18:26 -0400
          Re: Question about Pass-by-object-reference? emile <emile@fenx.com> - 2014-07-22 15:33 -0700
          Re: Question about Pass-by-object-reference? Jerry Hill <malaclypse2@gmail.com> - 2014-07-22 19:06 -0400
        Re: Question about Pass-by-object-reference? fl <rxjwg98@gmail.com> - 2014-07-22 15:31 -0700
          Re: Question about Pass-by-object-reference? emile <emile@fenx.com> - 2014-07-22 15:40 -0700
      Re: Question about Pass-by-object-reference? fl <rxjwg98@gmail.com> - 2014-07-22 16:00 -0700
        Re: Question about Pass-by-object-reference? emile <emile@fenx.com> - 2014-07-22 16:10 -0700
  Re: Question about Pass-by-object-reference? Terry Reedy <tjreedy@udel.edu> - 2014-07-22 20:27 -0400
    Re: Question about Pass-by-object-reference? fl <rxjwg98@gmail.com> - 2014-07-22 18:49 -0700
      Re: Question about Pass-by-object-reference? Ben Finney <ben+python@benfinney.id.au> - 2014-07-23 11:59 +1000
        Re: Question about Pass-by-object-reference? Steven D'Aprano <steve@pearwood.info> - 2014-07-23 05:35 +0000
          Re: Question about Pass-by-object-reference? Chris Angelico <rosuav@gmail.com> - 2014-07-23 16:07 +1000
          Re: Question about Pass-by-object-reference? Ben Finney <ben+python@benfinney.id.au> - 2014-07-23 16:25 +1000
          Re: Question about Pass-by-object-reference? Terry Reedy <tjreedy@udel.edu> - 2014-07-23 18:51 -0400
            Re: Question about Pass-by-object-reference? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-07-24 03:22 +0000
              Re: Question about Pass-by-object-reference? Steven D'Aprano <steve@pearwood.info> - 2014-07-24 05:05 +0000
    Re: Question about Pass-by-object-reference? Steven D'Aprano <steve@pearwood.info> - 2014-07-23 05:36 +0000
      Re: Question about Pass-by-object-reference? Terry Reedy <tjreedy@udel.edu> - 2014-07-23 18:32 -0400
    Re: Question about Pass-by-object-reference? alex23 <wuwei23@gmail.com> - 2014-07-25 15:20 +1000
  Re: Question about Pass-by-object-reference? Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2014-07-23 01:56 +0000

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