datetime/time quickie

[vurentjie]

On Sunday, 22 July 2012 at 21:16:22 UTC, Jonathan M Davis wrote:
> On Sunday, July 22, 2012 22:50:14 vurentjie wrote:
>> hi,
>> 
>> i can't seem to find how to do this in the docs ... simple 
>> example
>> 
>> i have 2 times 9:00,12:00 for which i need to get the interval
>> between them in minutes, ie 180
>> 
>> i though I could use Interval!TimeOfDay("9:00:00","12:00:00") 
>> and
>> convert this to minutes from here but this does not seem to be
>> correct.
>>
>> i have looked at Duration!(Tp)().total!"minutes"();
>> 
>> but i cant seem to figure out how to use Interval/Duration
>> together (without rolling out some kind of hacked intermediate
>> method)
>> 
>> any quick advice
>
> Okay. What do you mean by interval? Because it sounds to me 
> like you don't
> mean it in quite the same way that std.datetime does. A 
> Duration represents a
> duration of time which is not fixed in time at all (e.g. 3 
> hours), whereas an
> Interval represents a duration of time which is fixed (e.g. 3 
> hours starting at
> 9:00). If all you want is the amount of time between 9:00 and 
> 12:00, then you
> do
>
> auto diff = TimeOfDay(12, 0) - TimeOfDay(9, 0);
>
> If what you want is an Interval starting at 9:00 and going to 
> 12:00, then you
> need to call Interval's constructor properly. The example on 
> the constructor i
> the docs even shows how:
>
> Interval!Date(Date(1996, 1, 2), Date(2012, 3, 1));
>
> or
>
> Interval!Date(Date(1996, 1, 2), dur!"years"(3))
>
> In this case, you'd do something more like
>
> auto i = Interval!TimeOfDay(TimeOfDay(9, 0), TimeOfDay(12, 0));
>
> or
>
> auto  = Interval!TimeOfDay(TimeOfDay(9, 0), dur!"hours"(3));
>
> But it's sure not going to work with strings. _None_ of the 
> constructors in
> std.datetime take times or dates as strings. It's really only 
> units that are
> operated on as strings. You'd need to use the functions like 
> fromISOString or
> fromISOExtString on the various time point types to do a 
> conversion.
>
> You might want to read this article on std.datetime:
>
> http://dlang.org/intro-to-datetime.html
>
> - Jonathan M Davis

great thanks.. seems i skipped this page ...


auto duration = TimeOfDay.fromISOExtString("12:00:00") - 
TimeOfDay.fromISOExtString("09:00:00");
writeln(duration.total!"minutes"());

seems this is what i was looking for all along ... :)