Explanation of list reference
Rustom Mody
rustompmody at gmail.com
Sat Feb 15 12:47:08 EST 2014
On Saturday, February 15, 2014 9:59:59 PM UTC+5:30, Marko Rauhamaa wrote:
> Steven D'Aprano:
> > Object identity is simple and well-defined in Python. I don't know why
> > you are so resistant to this. Read the documentation.
> It is not defined at all:
In a certain way thats what I am saying. But you are saying it
stronger than I would... See below
> Every object has an identity, a type and a value. An object's
> identity never changes once it has been created; you may think of it
> as the object's address in memory. The 'is' operator compares the
> identity of two objects; the id() function returns an integer
> representing its identity.
> Thus "x and y are identical" *means* "x is y" and nothing else.
Formally yes.
But in practice, we (where we means experienced programmers and
presumably excludes persons like the OP) understand identity
'somehow-or-other'
What does that 'somehow-or-other' consist of?
I would argue that we do that comprehending-act by translating to
a kind of C. Maybe an informal, pidgin C but close enough that we get
(something of) the semantics.
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