A question on modification of a list via a function invocation

[nopsidy]

https://www.youtube.com/watch?v=pNe1wWeaHOU&list=PLYI8318YYdkCsZ7dsYV01n6TZhXA6Wf9i&index=1
Thank you,
-Alex Goretoy
http://launchpad.net/~a1g


On Wed, Sep 6, 2017 at 7:18 PM, Chris Angelico <rosuav at gmail.com> wrote:
> On Wed, Sep 6, 2017 at 10:11 PM, Rustom Mody <rustompmody at gmail.com> wrote:
>> On Wednesday, September 6, 2017 at 5:08:20 PM UTC+5:30, Steve D'Aprano wrote:
>>> On Wed, 6 Sep 2017 07:13 pm, Rustom Mody wrote:
>>>
>>>
>>> > Can you explain what "id" and "is" without talking of memory?
>>>
>>> Yes.
>>>
>>> id() returns an abstract ID number which is guaranteed to be an integer, and
>>> guaranteed to be distinct for all objects which exist at the same time. When an
>>> object ceases to exist, its ID number may be re-used.
>>>
>>> `is` compares the two operands for identity. If the two operands are the same
>>> object, `is` returns True, if they are distinct objects, `is` returns False.
>>
>>>>> a = (1,2)
>>>>> b = (1,2)
>>>>> a is b
>> False
>>>>> x = 1
>>>>> y = 1
>>>>> x is y
>> True
>>
>> a seems to be as 'same' to b as x is to y
>> Python seems to think otherwise
>>
>> Evidently your ‘same’ is not the same as mine??
>
> *facepalm*
>
> I got nothing to say to you. Have you been on this list all this time
> and still don't understand that Python sometimes optimizes immutables?
>
> ChrisA
> --
> https://mail.python.org/mailman/listinfo/python-list