[EMAIL PROTECTED] wrote: > Problem: > > You have a list of unknown length, such as this: list = > [X,X,X,O,O,O,O]. You want to extract all and only the X's. You know > the X's are all up front and you know that the item after the last X is > an O, or that the list ends with an X. There are never O's between > X's. > > I have been using something like this: > _____________________ > > while list[0] != O: > storage.append(list[0]) > list.pop(0) > if len(list) == 0: > break > _____________________ > > But this seems ugly to me, and using "while" give me the heebies. Is > there a better approach? > > hope this is clear.
>>> X = "X" >>> O = "O" >>> def fl(l): ... for i, v in enumerate(l): ... if v == O: ... return l[:i] ... return l ... >>> fl([X,X,X,X,O,O,O]) ['X', 'X', 'X', 'X'] >>> fl([]) [] >>> fl([O]) [] >>> fl([X]) ['X'] >>> regards Steve -- Steve Holden +44 150 684 7255 +1 800 494 3119 Holden Web LLC www.holdenweb.com PyCon TX 2006 www.python.org/pycon/ -- http://mail.python.org/mailman/listinfo/python-list
