Comparing lists ...

[Loic]

I would like to know if it is possible, and how to do this with Python:

I want to design a function to compare lists and return True only if
both lists are equal considering memory location of the list.
I suppose it would be the equivalent of comparing 2 pointers in c++

lets call this function check(a, b)
and define a few lists:

>>l0 = [1, 2, 3, 4]
l1 = [1, 2, 3, 4]
l2 = l0

I want it to have the following behaviour:

>>check(l1, l0)

False

>>check(l2, l0)

True

>>check(l1, l2)

False
Any idea how to do this with Python?

[James Stroud]

Loic wrote:

I would like to know if it is possible, and how to do this with Python:

I want to design a function to compare lists and return True only if
both lists are equal considering memory location of the list.
I suppose it would be the equivalent of comparing 2 pointers in c++

lets call this function check(a, b)
and define a few lists:

>>l0 = [1, 2, 3, 4]
>>l1 = [1, 2, 3, 4]
>>l2 = l0

I want it to have the following behaviour:

>>check(l1, l0)

False

>>check(l2, l0)

True

>>check(l1, l2)

False
Any idea how to do this with Python?

Use "is". E.g.:

l0 is l1

James

[Paul Rubin]

Loic <lo**@spam.mewrites:

I want to design a function to compare lists and return True only if
both lists are equal considering memory location of the list.
I suppose it would be the equivalent of comparing 2 pointers in c++

Use the "is" keyword.

print (l1 is l2)
print (l0 is l2)