On Thu, Apr 21, 2011 at 7:38 PM, vino19 <vinogra...@gmail.com> wrote: > Hello, I'm a newbie. > What's the defference between > >>>>a=-6; b=-6; a is b >>>>True > > and > >>>>a=-6 >>>>b=-6 >>>>a is b >>>>False
You may want to use the == operator rather than "is". When you use "is", you're asking Python if the two variables are referencing the exact same object, but with ==, you're asking if they're equivalent. With integers from -1 to 99, Python keeps singletons, which means that your test would work if you used 6 instead of -6; but there's no guarantee of anything with the negatives. However, it doesn't matter whether the variables are pointing to the same object or not, if you use ==, because two different objects holding the number -6 will compare equal. Hope that clarifies it! Chris Angelico -- http://mail.python.org/mailman/listinfo/python-list
