On Apr 3, 6:05 pm, Steven Bethard <[EMAIL PROTECTED]> wrote:
> bahoo wrote:
> > The larger problem is, I have a list of strings that I want to remove
> > from another list of strings.
>
> If you don't care about the resulting order::
>
> >>> items = ['foo', 'bar', 'baz', 'bar', 'foo', 'frobble']
> >>> to_remove = ['foo', 'bar']
> >>> set(items) - set(to_remove)
> set(['frobble', 'baz'])
I'm surprised no one has mentioned any of the methods of set. For
instance:
>>> set.difference.__doc__
'Return the difference of two sets as a new set.\n\n(i.e. all
elements that are in this set but not in the other.)'
>>>set(items).difference(to_remove)
set(['frobble', 'baz'])
There are a few other cool methods of sets that come in handy for this
sort of thing. If only order could be preserved.
>
> If you do care about the resulting order::
>
> >>> to_remove = set(to_remove)
> >>> [item for item in items if item not in to_remove]
> ['baz', 'frobble']
>
> STeVe
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