[Tutor] working with time spans ?

[Michele Alzetta]

Il sab, 2004-06-05 alle 01:30, Tim Peters ha scritto:

> > shiftperiod = TimeSpan(periodend,periodstart)
> 
> The order of the arguments is backwards there, isn't it? 

copied wrongly, of course

> This does the same thing (but where I swapped the order of arguments as
> noted above):
> 
> class TimeSpan(object):
>     def __init__(self, startimetuple, endtimetuple):
>         self.starttime = startimetuple
>         self.endtime = endtimetuple
> 
>     def __contains__(self, timespan):
>          return (self.starttime <= timespan.starttime and
>                  self.endtime >= timespan.endtime)

Yes, but this can contain any tuple, which means I can't extract
self.startime and feed it in to one of the time functions if I ever
wanted to.

> You'll eventually want to think about using the datetime module.  Doing so
> will check that the dates passed in are sane, and provide a strong base to
> build fancier stuff on.  For example, just replace the first 4 lines above
> with:
> 
> from datetime import datetime
> 
> class TimeSpan(object):
>     def __init__(self, startimetuple, endtimetuple):
>         self.starttime = datetime(*startimetuple)
>         self.endtime = datetime(*endtimetuple)
> 
> Everything else works the same then, and not even the __contains__ method
> needs to change.  You can easily add other interesting methods to your
> TimeSpan class then; e.g., add
> 
>     def length(self):
>         return self.endtime - self.starttime
> 
> and then
> 
> print shiftperiod.length()
> print shift1.length()
> print shift2.length()
> 
> prints
> 
> 30 days, 0:00:00
> 12:00:00
> 12:00:00

That's really great. 
Er ... what on earth does the "*" in *startimetuple mean ?

-- 
Michele