[Python-ideas] Please reconsider the Boolean evaluation of midnight

[M.-A. Lemburg]

On 06.03.2014 11:46, Antoine Pitrou wrote:
> Le 06/03/2014 11:33, M.-A. Lemburg a écrit :
>>
>> I find it strange that the only argument against having time(0,0,0)
>> evaluate to False in a boolean context is a wrongly used
>> None test.
> 
> It's only "wrongly used" because of that particular wart.
> In other words, the "wrongly used" None test *exposes* the wart, it is not its *cause*.

Wait. Let's be clear on this:

Writing

    if x: print ('x is None')

or

    if x == None: print ('x is None')

is wrong code.

None is a singleton, so you have to use the "is" operator, i.e.

    if x is None: print ('x is None')

is the only correct way of testing for None.

Adding a test to pylint for this would probably be more helpful
and address the real problem in a more productive way, than the
current discussion to making the above problematic code work in
the single use case of x being a datetime.time object.

> There are other contexts with implicit boolean conversion, such as any() and all().

If you expect those to work correctly for None testing, then
you're writing wrong code as well.

-- 
Marc-Andre Lemburg
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