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True is True / False is False?


On Thu, Jul 23, 2020 at 5:51 AM Tim Chase <python.list at tim.thechases.com> wrote:
>
> On 2020-07-22 11:54, Oscar Benjamin wrote:
> >> On Wed, Jul 22, 2020 at 11:04 AM Tim Chase wrote:
> >>> reading through the language specs and didn't encounter
> >>> anything about booleans returned from comparisons-operators,
> >>> guaranteeing that they always return The One True and The One
> >>> False.
> >>
> >> That said, though, a comparison isn't required to return a bool.
> >> If it *does* return a bool, it has to be one of those exact two,
> >> but it could return anything it chooses. But for built-in types
> >> and most user-defined types, you will indeed get a bool.
> >
> > I'm not sure if this is relevant to the question but thought I'd
> > mention concrete examples. A numpy array will return non-bool for
> > both of the mentioned operators
>
> that is indeed a helpful data-point.  Do you know of any similar
> example in the standard library of things where comparison-operators
> return something other than True or False (or None)?
>

Can't think of any (although that doesn't disprove it). Also, nothing
returns None from a comparison, to my knowledge.

ChrisA