A certainl part of an if() structure never gets executed.

[Ferrous Cranus]

On 16/6/2013 1:42 μμ, R. Michael Weylandt wrote:
>>
>> I believe you are mistaken.
>>
>> a here is not a pointer but variable,
>> which is a memory location that stores value 6.
>>
>> b here is a pointer. It's value is the memory location of variable a which
>> stores value 6.
>>
>> c here is just te same as a , a variable.
> Actually, y'all both might be. This is a bit CPython specific and not
> mandated by the language specification.
>
> To Nikos: please don't extrapolate from the examples below. They are a
> CPython (the most common implementation of the Python language)
> specific detail.
>
> ## CODE SNIPPET##
> a = 6; b = a; c = 6
>
> id(a)
> id(b)
> id(c)
> ## END CODE##
>
> These are all the same, indicating that they all point to the "same 6"
> in memory. That's a CPython specific optimization (caching small
> integers) which is not guaranteed by the language and changes between
> pythons and between compiles.
>
> For example,
>
> ## CODE SNIPPET##
> a = 552315251254
> b = a
> c =  552315251254
>
> a is b # True _on my machine_

I accept this if in the premise that, b boils down to actually point to 
a's value, but it has to go through a first to find it, not directly.

> a is c # False _on my machine_

Why false?  These are 2 different memory locations storing the same number.
This should have been True.

Looks very weird.

a = memory location storing a value
b = memory location storing a's memory location
c = memory location storing a value, the same value as a

> id(a)
> id(b)
> id(c)
> ## END CODE##
>
> Note that to compare if two names point to the same "object, you can
> use the "is" operator.
>
> a is b
> c is a
>
> etc.

what id() does, never heard of that function before.



-- 
What is now proved was at first only imagined!