[Tutor] permutations?

Francesco Loffredo fal at libero.it
Wed Dec 15 10:43:16 CET 2010

On 14/12/2010, Brett Ritter and Dave Angel wrote:
> Francesco Loffredo wrote:
>>> ...
>>> mylist[:] = [x for x in mylist if x != "something"]
>>> vs.
>>> mylist = [x for x in mylist if x != "something"]
>>> ...

> mylist[:] is a slice of mylist (you know that).  If you ASSIGN it to
> something, you'll get a copy of that slice, but if you modify it
> you're modifying the list in place.
 > ...

> ...
> On the left side of an assignment, a slice operator specifies which part of an existing object gets replaced by the right side. So
> whenever you have a list that's referred to by more than one symbol, you may want to use a syntax like this.
> The slice operator does a very different thing inside an expression (eg. on the right side of an assignment).

                             *THANK YOU BOTH!*
This is something I overlooked, and I'm very happy you made me understand it.

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