Brian D wrote: [...] > I'm definitely acquiring some well-deserved schooling -- and it's > really appreciated. I'd seen the "is/is not" preference before, but it > just didn't stick. > Yes, a lot of people have acquired the majority of their Python education from this list - I have certainly learned a thing or two from it over the years, and had some very interesting discussions.
is/is not are about object identity. Saying a is b is pretty much the same thing as saying id(a) == id(b) so it's a test that two expressions are references to the exact same object. So it works with None, since there is only ever one value of <type 'NoneType'>. Be careful not to use it when there can be several different but equal values, though. > I see now that "pass" is redundant -- thanks for catching that. > regards Steve -- Steve Holden +1 571 484 6266 +1 800 494 3119 PyCon is coming! Atlanta, Feb 2010 http://us.pycon.org/ Holden Web LLC http://www.holdenweb.com/ UPCOMING EVENTS: http://holdenweb.eventbrite.com/ -- http://mail.python.org/mailman/listinfo/python-list
