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From: Ethan Furman <ethan@stoneleaf.us>
Newsgroups: comp.lang.python
Subject: Re: Drowning in a teacup?
Date: Sat, 02 Apr 2016 16:15:53 -0700
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On 04/02/2016 12:54 PM, Random832 wrote:
> On Sat, Apr 2, 2016, at 15:28, Ned Batchelder wrote:
>> On Friday, April 1, 2016 at 4:27:30 PM UTC-4, Fillmore wrote:
>>> notorious pass by reference vs pass by value biting me in the backside
>>> here. Proceeding in order.
>>
>> As others have pointed out, this is false dichotomy.  There are other
>> possibilities than pass by reference and pass by value.  Python (and
>> many other languages) use something called pass by object or pass by
>> sharing.
>
> I think that this arises from a confusion as to what a "value" is in
> "pass by value".
>
> The point of it being pass by value is that there is no statement you
> can execute in the function that has the effect of an assignment of the
> expression that was passed in from the caller. This holds no matter what
> kind of object is passed in or what mutable properties it has or does
> not have.

Also, if "pass-by-value" is being used, even mutation of the passed 
object will not show up in the caller.

--
~Ethan~