A strange behavior of list.extend()

[sdhyok]

I think the two script should produce the same results, but not.
Why?

---------------- Script #1
ls = [1]
ls.extend([2,3])
print ls
-> [1,2,3]

--------------- Script #2
ls = [1].extend([2,3])
print ls
-> None

Daehyok

[mackstann]

On Sun, Aug 24, 2003 at 02:11:15PM -0700, sdhyok wrote:

I think the two script should produce the same results, but not.
Why?

---------------- Script #1
ls = [1]
ls.extend([2,3])
print ls
-> [1,2,3]

--------------- Script #2
ls = [1].extend([2,3])
print ls
-> None

list.extend happens in place and returns None, so your ls variable is
just getting the returned None. Same thing happens with sort:

[4,2,3,1].sort()

or:
f = [4,2,3,1]
f.sort()
f

[1, 2, 3, 4]
--
m a c k s t a n n mack @ incise.org http://incise.org
Excellent time to become a missing person.

[sdhyok]

Thanks. I got it.

Deahyok