Re: DURATION vs DTEND

[Dan Winship <danw@xxxxxxxxxx>]

On Wed, 2003-04-02 at 12:48, John Stracke wrote:
> Dan Winship wrote:
> 
> >>From cap-10 6.1.1.10:
> >
> >   As "DTEND" value is the first time that is excluded from a components
> >   time range, any "DURATION" value supplied by the "QUERY" property
> >   value that is exactly one second less than the "DTEND" property value
> >   MUST match the QUERY.  And if the "DURATION" property value ends
> >   exactly at the computed DTEND it MUST NOT match.
> >
> >etc. That's wrong, right? DTSTART + DURATION == DTEND, not DTEND - 1
> >  
> >
> No, the text looks right.  That first clause ("...first time that is 
> excluded...") says we're dealing with a half-open interval.

Yes, exactly.

How many integers are there in the half-open interval [0,1)? One.
So how many seconds are there in the half-open interval
[12:00:00,12:00:01)? I'd say 1 again, but according to the cap spec's
math, an event that starts at 12:00:00 and ends at 12:00:01 has a
duration of 0 seconds.

-- Dan