PEP 308: A PEP Writer's Experience - PRO

[Fredrik Lundh]

Paul Rubin wrote:

> I think Andrew Koenig pointed out a third argument which many of us
> had perhaps underestimated: it can prevent bugs.  A lot of the
> workarounds attempted for its absence are flat out wrong.  He gives an
> example showing finding the maximum of x and y with
>
>    x > y and x or y
>
> which looks reasonable and might even pass the initial unit tests of a
> real program, but gives the wrong answer (zero) if x is 0 and y is
> negative.  A conditional expression like
>
>    x if (x > y) else y
>
> is much harder to get wrong.

in Python, that's spelled:

    max(x, y)

</F>