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

[Donald Stufft]

On Mar 5, 2014, at 5:27 PM, M.-A. Lemburg <mal at egenix.com> wrote:

> 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).

Except time isn’t number of seconds since midnight. 

> 
> -- 
> Marc-Andre Lemburg
> eGenix.com
> 
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-----------------
Donald Stufft
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