On Jun 13, 11:34 am, "Gabriel Genellina" <[EMAIL PROTECTED]> wrote: > En Fri, 13 Jun 2008 04:37:44 -0300, Nader <[EMAIL PROTECTED]> escribió: > > > Hello, > > > I read some files name from a directory and then I put these name in a > > list. I will check whether it is empty or not, and I would do it with > > an exception. With if statement it is very simple: > > > If list_of_files != "" : # this can be if list_of_files != > > []: > > get the files > > elas: > > there is no file > > If it is simple, just do it! Why do you want to make things more > complicated? This would be enough: > > if list_of_files: > get_the_files(list_of_files) > else: > print "there is no file" > > (a list has a false boolean value when it is empty) > > > But with exception, I can write something as: > > > try: > > list_of_files != [] > > get the files > > except ValueError: > > Print " there is no file" > > > What can the first statement be inside 'try' if I don't want to use if > > statement? > > If you insist on using an exception (and assuming list_of_files is > actually a list, not a string or other kind of sequence): > > try: > list_of_files[0] > except IndexError: > ...no files... > > This way you're checking that list_of_files contains at least one element. > But I would not reccomend it. > > -- > Gabriel Genellina
I would accept your suggestion in raltion of checking a list whether it is empty or not with "if" statement. It is more expressive and clear. But In this case I would learn more about the "try .... except" exception. Nader -- http://mail.python.org/mailman/listinfo/python-list
