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

[M.-A. Lemburg]

On 05.03.2014 23:10, Donald Stufft wrote:
> 
> On Mar 5, 2014, at 5:04 PM, M.-A. Lemburg <mal at egenix.com> wrote:
> 
>> I don't know what all the fuzz is about. There are lots of types
>> in Python that evaluate to False in certain corner cases, e.g.
>> "", (), [], {}, 0, 0.0, 0j, None, etc.
>>
>> datetime.time(0,0,0) is just another one :-)
>>
> Most of those are pretty easy to reason about being “False”, they all have some
> concept of empty, nothing, etc. Midnight however is not any more or less a time
> than one minute past midnight. Even worse, if you consider not explicitly
> checking for None a bug in that application code, debugging that code is made
> much more difficult because of the fact that for some reason "midnight" is
> considered False.

The reasoning becomes clear if you regard a time value as
number of seconds since midnight (the time of day is a relative
measure). This is 0 for time(0,0,0).

-- 
Marc-Andre Lemburg
eGenix.com

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