[Python-Dev] RE: Re: PEP 285: Adding a bool type (original) (raw)

Gerald S. Williams gsw@agere.com
Wed, 3 Apr 2002 15:02:02 -0500

Guido van Rossum wrote:

Tutorial should point this out. It's poor coding style even in languages that do have strict Booleans, so I think it's a good idea to nip this one in the bud.

Agreed, although one of Python's big selling points (for me, at least) is that you generally don't have to refer to the manual to understand what's happening, even if you're new to the language.

And something like this may be a bit more subtle, since it is somewhat an issue of style. I don't expect people to go to this extreme:

if (a > b) is True: ...

But that would be valid code. There's probably somebody in the world who would even prefer the useless "is True".

What a waste to write "if bool(y) == True" instead of "if y" ... :-(

True again. I think we all agree that comparisons to True and False would cause problems. I guess the question is how often people would actually get tripped up by it. Or worse, not get tripped up by it and start doing it regularly. :-)

I was thinking you could simply attack the problem by doing something with the == and != operators, but that doesn't help if you test using "is" or "is not". I'm not sure if managing people's expectations ever really works, but perhaps that's the only real answer (assuming the PEP is implemented).

-Jerry

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