> -----Original Message----- > From: Tutor [mailto:tutor-bounces+crk=godblessthe...@python.org] On > Behalf Of Alan Gauld > Sent: Sunday, August 02, 2015 3:01 PM > To: tutor@python.org > Subject: Re: [Tutor] scratching my head > > On 02/08/15 22:44, Clayton Kirkwood wrote: > > > for dir_path, directories, files in os.walk(main_dir): > > for file in files: > > # print( " file = ", file) > > # if( ("(\.jpg|\.png|\.avi|\.mp4)$") not in file.lower() ): > > Python sees that as a single string. That string is not in your filename. > > > # if( (".jpg" or ".png" or ".avi" or ".mp4" ) not in file.lower() > > Python sees that as a boolean expression so will try to work it out as a > True/False value. Since a non empty string is considered True and the first > True expression makes an OR opeation True overall it returns ".jpg" and tests > if it is not in the filename. > > > #except by the drudgery below. I should be able to just have a list, > > maybe from a file, that lists all > > You might think so but that's not how 'in' works. > > But you could use a loop: > > found = False > for s in (".jpg",".png",".avi",".mp4"): > found = test or (s in file.lower()) if not found: ...
The for is much better and it's able to get input from a file. I would think Python more sensible if something like my commented one would work. That would make more sense to me. Thanks > > > if( ".jpg" not in file.lower() and > > ".png" not in file.lower() and > > ".avi" not in file.lower() and > > ".mp4" not in file.lower() ): > > Whether that's any better than your combined test is a moot point. > > HTH > -- > Alan G > Author of the Learn to Program web site > http://www.alan-g.me.uk/ > http://www.amazon.com/author/alan_gauld > Follow my photo-blog on Flickr at: > http://www.flickr.com/photos/alangauldphotos > > > _______________________________________________ > Tutor maillist - Tutor@python.org > To unsubscribe or change subscription options: > https://mail.python.org/mailman/listinfo/tutor _______________________________________________ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: https://mail.python.org/mailman/listinfo/tutor
