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"]
...
Brett:
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.
> ...
Dave:
...
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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