Return value of an assignment statement?

[Aahz]

In article <AcWdnVgsAZnOwCPanZ2dnUVZ_oTinZ2d at comcast.com>,
Jeff Schwab  <jeff at schwabcenter.com> wrote:
>Aahz wrote:
>> In article <5MSdncSVGdGriCPanZ2dnUVZ_vPinZ2d at comcast.com>,
>> Jeff Schwab  <jeff at schwabcenter.com> wrote:
>>> bruno.desthuilliers at gmail.com wrote:
>>>>
>>>> There's nothing like a variable "storing" anything in Python. All you
>>>> have are names to (references to) objects binding in a namespace. Now
>>>> the fact is that some types are mutable and other are not. In your
>>>> above example, the augmented assignment does *not* rebind a, but
>>>> invoke a.extend(). With integers, it would have rebind a. So while
>>>> your observation is exact, your interpretation is wrong !-)
>>> Thank you for the clarification.  For some reason, I had it in my head 
>>> that ints were packed directly into the C structures that represent 
>>> Python variables, in the same (union?) member that otherwise would store 
>>> a pointer.
>> 
>> Notice very very carefully that Bruno is not using "variable".  Many
>> expert Python programmers strongly prefer to talk about "names" instead
>> of "variables" (especially when explaining the Python object model)
>> precisely because using "variable" leads to incorrect expectations.
>> 
>> http://starship.python.net/crew/mwh/hacks/objectthink.html
>
>So what is the "variable?"  Or is Python the first HLL I've ever heard 
>of that didn't have variables?

Whether Python has "variables" depends on your perspective.  Python
certainly does *not* have variables with anything like the semantics of
C/C++ variables.  For that reason, it's often convenient to shift the
vocabulary to avoid misunderstading.  However, the vast majority of
Python programmers do use "variable" in casual conversation (I certainly
do); it's only when trying to discuss the Python object model that
there's a strong tendency to switch to using "names".
-- 
Aahz (aahz at pythoncraft.com)           <*>         http://www.pythoncraft.com/

"All problems in computer science can be solved by another level of     
indirection."  --Butler Lampson