On Jan 31, 2013, at 7:35 AM, Dean Troyer <dtroyer at gmail.com> wrote: > On Thu, Jan 31, 2013 at 8:52 AM, Dolph Mathews <dolph.mathews at gmail.com> wrote: >> +1 for "X not in Y" >> >> "not X in Y" reads ambiguously to me. > > And there's the reason it matters...it actually is not ambiguous > according to operator precedence rules > (http://docs.python.org/2/reference/expressions.html#not-in): > > in "X not in Y" 'not' is part of the membership operator > > in "not X in Y" 'not' is a boolean operator on X, returning True or False The in operator has precedence over not so to have not be an operator on X you would need: (not X) in Y IMO, it seems a little excessive to require one form over the other, but I slightly prefer X not in Y as well. Vish > > These really are different operations that may have the same result > for some data types and values. Phew! There is still only one way to > do it right... > > dt > > -- > > Dean Troyer > dtroyer at gmail.com > > _______________________________________________ > OpenStack-dev mailing list > OpenStack-dev at lists.openstack.org > http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev