Devin Jeanpierre wrote: > On Fri, Jul 6, 2012 at 6:46 PM, Ethan Furman <ethan at stoneleaf.us> wrote: >> It's checking for equality, not identity. > > >>> x = float('nan') > >>> x in [x] > True > > It's checking for equality OR identity. Good point. In my case, checking for equality will cover both cases. ~Ethan~