Hi Flavio,
[snipped]
>
> Hi,
>
> I'm sorry to bother you, but I really need to know if this makes sense
> to you.
No bother at all, mail from you or Dave is always welcome :-)
I have looked at the changes that you have provided and there
are some points that I simply don't understand. Bear in mind
that this is comming from a junior level programmer (me)
> We are still working on the DateTime::Set API and docs, and
> you are the first user :)
Wow!!, What about Rick Measham (author of the easter module)?
We may want to get him involved as well.
>
>
> Flavio S. Glock wrote:
> >
> > Hill, Ronald wrote:
> > > What I wanted to accomplish is to have the module accept a
> > > DateTime::Set object compute the rise/set times and return a new
> > > DateTime::Set object. Here is what I have done:
[my code snipped]
> > You could build a recurrence:
> >
> > sub sunrise_as_set {
> > my $self = shift;
> > my $class = ref($self);
> > return DateTime::Set->new( recurrence =>
> > $class::following_sunrise
> > );
> > }
OK so far, However, I would need to change my sub for this
(following_sunrise).
Currently, I return both rise/set times. I would need to break this down
to return just the sunrise only. No problem with that.
> >
> > sub sunset_as_set {
> > my $self = shift;
> > my $class = ref($self);
> > return DateTime::Set->new( recurrence =>
> $class::following_sunset );
> > }
Add a sub (following_sunset) again, no problems here just return
sunset only.
> >
> > Now, since you have rise/set times, you can build a
> > "DateTime::SpanSet", which is a set of intervals.
> >
> > We haven't finished the discussion on what is the syntax
> > for creating a DateTime::SpanSet, but it would be something like this:
> >
> > sub daytime_as_spanset {
> > my $self = shift;
> > my $class = ref($self);
> > my $sunrises = $self->sunrise_as_set;
> > my $sunsets = $self->sunset_as_set;
> > return $sunrises->until( $sunsets );
> > }
maybe sunrise_as_spanset? (land of the midnight sun)
> >
> > sub nighttime_as_spanset {
> > my $self = shift;
> > my $class = ref($self);
> > my $sunrises = $self->sunrise_as_set;
> > my $sunsets = $self->sunset_as_set;
> > return $sunsets->until( $sunrises );
> > }
> >
sunset_as_spanset?
[more of my code snipped]
> >
> > my $dt_span = DateTime::Span->new( begin => $dt1, end => $dt2 );
> >
OK generate the range of dates to search through.
> > > my $easter = $easter_sunday->as_set(from=>$dt1, to=>$dt2,
> inclusive=>1);
> >
> > # I would expect $easter_sunday->as_spanset to return
> > # the time from sunday 00:00 until 23:59
> > $easter = $easter_sunday->as_spanset->intersection( $dt_span );
This is what is throwing me for a loop. The easter_sunday method
is returning a date (year,month,day) with no time information
because it does not matter what time it is. Weather it is
noon or 3:00PM it is still easter!
> >
[snipped]
> >
> > my $set2 = $sunrise->daytime_as_spanset->intersection ( $easter );
This took my some time to understand because of the term intersection.
When I see this I think of union, intersection in terms of arrays ie:
finding union of arrays intersection (differences) of arrays. However,
in context of your module, it means a while loop. This may need some
clarification in the documentation/examples.
> >
[snipped]
> >
> > I think we could just have a
> > $set = $set->time_zone( 'America/Los_Angeles' );
> > method (but we don't have it yet).
I think this is a requirement to be able to set the timezone
in one swoop!
> >
> > All this might seem a bit strange, but the idea of using
> > sets is that
> > you don't have to use iterators -- you use set operations instead.
> > (you can also 'print $set' )
To me, most of this is very new. I am having a hard time getting use
to using the set operations. But with time I should get use to it.
> >
> > Now show it:
> >
> > my $iter = $set2->iterator;
> > while ( my $dt = $iter->next ) {
> > print $dt->begin->datetime ." until ".
> $dt->end->datetime ."\n";
> > }
This looks good, just loop through and print.
All in All the concepts you have implemented in the module
sound great and will vastly improve dealing with date lists.
I hope this helps,
Thanks
Ron Hill
