On 28/09/10 01:46, Jerry Hill wrote:
The way you've written it obviously works fine. That being said, I'd probably do something like this:from string import ascii_lowercase, ascii_uppercase, digits, punctuation def complex_password(password): '''Checks to make sure a password is complex''' checks = [ lambda p: len(p)> 12, lambda p: any(c in punctuation for c in p), lambda p: any(c in digits for c in p), lambda p: any(c in ascii_uppercase for c in p), lambda p: any(c in ascii_lowercase for c in p), ] return all(check(password) for check in checks) if __name__ == '__main__': passwords = ['password', 'Password1234567', 'Password1.234567'] for password in passwords: print password, complex_password(password) In the complex_password function, I create a list of tests, each of which is a function that returns either true or false. In this case I used lambdas to create the function objects, since all the tests easily fit on a single line, but it would be fine to define a function elsewhere and use it in the list if you had more complicated checks to do. all() is a built in function that returns True if all of the elements in an iterable are true (or the iterable is empty), and otherwise returns False. That seems like an ideal way to execute a bunch of tests and return True if all of them pass, and otherwise return false. In this case, the iterable is a generator expression that evaluates each of the rules with the supplied password. any() is similar, but it returns True if any member of the iterable is True. Looking back at it, I probably should have used longer variable names in my rules, which would have made them a bit easier to read. When I was writing them, I was worried about the lines getting too long with longer names. It didn't turn out to be a problem though.
After doing a bit more reading and trying out some of the very useful suggestions people have made in this thread, I've decided to rework that section based on your example.
I was trying to use lambdas to solve this earlier but it's new territory for me and I couldn't figure out how to string them together as you've done above. The explanation is especially invaluable, thanks.
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