[Python-Dev] Interop between datetime and mxDateTime

[Tim Peters]

[Fredrik Lundh]
> the last revision of the "time type" proposal seems to suggest that all
> time types should implement the following interface:

Calling T datetime.time, and D datetime.datetime:

>     tm = timeobject.timetuple()

D yes, T no.

>     cmp(timeobject, timeobject)

Both yes, but not a mix of D and T.

>     hash(timeobject)

Both yes.

It's curious that that the minimal API doesn't have a way to create a
timeobject ab initio (the only operations here with a timeobject output need
a timeobject as input first).

> and optionally
>
>     deltaobject = timeobject - timeobject

D yes, T no.

>     floatobject = float(deltaobject) # fractional seconds

datetime.timedelta doesn't have anything like that, but it could be useful.
Converting a timedelta to minutes (or seconds, or whatever) is painful now.
I'd rather see explicit .toseconds(), .tominutes() (etc) methods.  A caution
that an IEEE double doesn't necessariy have enough bits of precision so that
roundrip equality can be guaranteed.  I expect you'd also need an API to
create a delta object from a number of seconds (in datetime that's spelled

    datetime.timedelta(seconds=a_float_int_or_long)

).

>     timeobject = timeobject + integerobject

Neither, and unclear what it means (is the integer seconds?  milliseconds?
days?  etc).

>     timeobject = timeobject + floatobject

Neither, likewise.

>     timeobject = timeobject + deltaobject

D yes, T no.