Le Wednesday 30 July 2008 16:46:37 [EMAIL PROTECTED], vous avez écrit : > Hello, > > I have a long list of memory-heavy objects that I would like to access > in differently sorted order. Let's say I'd like to have lists called > by_date or by_size that I can use to access the objects in the > specified order. > ... > I know there is a thing called "shallow copy" that has something to do > with not duplicating memory content but I don't understand the > concept. Maybe that's what would help here, too. >
In fact, all containers in python contains references of objects. >>>[54]: a = [1] >>>[55]: b = [a] >>>[56]: c = list(sorted(b)) >>>[57]: b, c ...[57]: ([[1]], [[1]]) >>>[58]: b.append(3) >>>[59]: b, c ...[59]: ([[1], 3], [[1]]) >>>[60]: a.append(0) >>>[61]: b, c ...[61]: ([[1, 0], 3], [[1, 0]]) This is if you want to make a true copy (called deep copy) that you'll have to do extra steps (using copy module for example). -- _____________ Maric Michaud -- http://mail.python.org/mailman/listinfo/python-list
