[Tutor] Why is this only catching one occurance?

[Chris Hengge]

I've tried to use your example:
for unWantedItem in directoryList[,,-1]:

but I get an error:
for unWantedItem in directoryList[,,-1]:
                                                 ^
SyntaxError: invalid syntax

I understand what you are saying to do, and it makes sense, but I'm not sure
how to impliment it.

On 10/27/06, Bob Gailer <bgailer at alum.rpi.edu> wrote:
>
> Chris Hengge wrote:
> > Here is my code:
> > for unWantedItem in directoryList:
> >             try:
> >                 if "hex" in unWantedItem.lower():
> >                     if not "bmc" in unWantedItem.lower():
> >                        print unWantedItem + " removed!"
> >                        directoryList.remove(unWantedItem)
> >
> > This only seems to loop through once, and removes 1 of 2 occurances
> > from this list that should be captured. Should "for" keep the list
> > going through each instance?
> "for" goes thru the list accessing item[0], item[1], item[2], etc. Let's
> say "for" is on item[1] and you remove item[1]. All the subsequent items
> "move left", so item[2] becomes item[1], item[3] becomes item[2], etc.
> "for" then steps to item[2], skipping the original item[2].
>
> There are several ways around this. The easiest is to process the list
> backwards: for unWantedItem in directoryList[,,-1]:
>
> --
> Bob Gailer
> 510-978-4454
>
>
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