Well, I am not convinced of the equivalence of not None and true: >>> not None True >>> 3 is True; False >>> 3 is not None True >>>
P.S. Sorry for the top-post -- is there a way to not do top posts from gmail? I haven't used usenet since tin. On Thu, Aug 5, 2010 at 11:56 AM, Roald de Vries <downa...@gmail.com> wrote: > On Aug 5, 2010, at 5:42 PM, wheres pythonmonks wrote: >> >> How does "x is not None" make any sense? "not x is None" does make sense. >> >> I can only surmise that in this context (preceding is) "not" is not a >> unary right-associative operator, therefore: >> >> x is not None === IS_NOTEQ(X, None) >> >> Beside "not in" which seems to work similarly, is there other >> syntactical sugar like this that I should be aware of? > > 'not None' first casts None to a bool, and then applies 'not', so 'x is not > None' means 'x is True'. > 'not x is None' is the same as 'not (x is None)' > > Cheers, Roald > -- > http://mail.python.org/mailman/listinfo/python-list > -- http://mail.python.org/mailman/listinfo/python-list
