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Date: Sun, 26 Aug 2012 00:25:06 -0500
From: Evan Driscoll <driscoll@cs.wisc.edu>
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To: "Steven D'Aprano" <steve+comp.lang.python@pearwood.info>
Subject: Re: Re: Objects in Python
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On 08/24/2012 10:04 PM, Steven D'Aprano wrote:
> The fact that the end result is the same is hardly surprising -- Python's
> VM is built on top of C pointer indirection, so of course you can start
> with pointers and end up with Python semantics. But the practice of
> coding are very different:
>
> * in C, I care about identifiers ("names") in order to explicitly manage
> addresses and pointers as a means to reach the data I actually care about;
>
> * in Python, I care about identifiers in order to reach the data I
> actually care about.
>
So I find this comment very interesting. It makes me wonder if the root 
cause of our (pretty minor) disagreement is in some sense related to our 
mental models of *C* variables. I'm actually not much of a C programmer 
specifically, but I do a lot of C++ stuff. Of those two descriptions, 
I'd actually say that the Python description sounds more like how I 
think about variables in C++ most of the time.

Obviously there are differences between value and reference semantics 
between the two languages, but thinking about some variable being 
located at some address in memory is something that I actually do pretty 
rarely; I basically think of variables as naming data, and addresses 
mostly come into play when thinking about points-to and aliasing 
information at a more abstract level, much the same as I do in Python.

Evan