[Python-ideas] Changing the meaning of bool.__invert__

[Ian Kelly]

On Sun, Apr 17, 2016 at 12:24 PM, Pavol Lisy <pavol.lisy at gmail.com> wrote:
> 2016-04-09 17:43 GMT+02:00, Steven D'Aprano <steve at pearwood.info>:
>> flag ^ flag is useful since we don't have a boolean-xor operator and
>> bitwise-xor does the right thing for bools. And I suppose some people
>> might prefer & and | over boolean-and and boolean-or because they're
>> shorter and require less typing. I don't think that's a particularly
>> good reason for using them, and as you say, you do have to guard
>> against non-bools slipping, but Consenting Adults applies.
>
> They are also useful if you need to avoid short-circuit evaluation.

One can easily write functions to do that.

    def long_or(a, b):
        """Equivalent to a or b but always evaluates both expressions."""
        return a or b

long_or(a, b) may not be as pretty as a | b, but I'll argue that it's
more readable since it's up-front about its intent, whereas a | b
looks like it could just be a mistake.