Time Delta

[Rick Measham]

At 5:07 PM +1000 2/10/03, Scott Penrose wrote:
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>I am trying to do the age old problem...
>
>* Here is DateTime 1
>* Here is DateTime 2
>* Here is the working week (Mon-Fri, 9-5) (or whatever we define)
>* Tell me the working hours between DateTime 1 and DateTime 2
>
>eg:
>
>   DateTime 1              DateTime 2              Difference
>
>   19/8/2003 16:35         20/8/2003 11:15         2:40
>
>or - 2 hours, 40 minutes
>
>What is the simplest, shortest way.


G'day Scott,
I promised a few months back to talk about DateTime sometime soon. 
Tell me when and I'll be there. The following *should* solve your 
problem, but doesn't. I get a strange error at the end when creating 
the intersection. To solve this (and maybe to get a better answer) 
I've CC'd this to the DateTime mailing list.

G'day DateTimers,
Any clues on why the intersections don't create properly?



use DateTime;
use DateTime::Span;
use DateTime::Set;
use DateTime::SpanSet;

use Data::Dumper; # For displaying results

$datetime1 = DateTime->new(
	year => 2003,
	month => 8,
	day => 19,
	hour => 16,
	minute => 35
);
$datetime2 = DateTime->new(
	year => 2003,
	month => 8,
	day => 20,
	hour => 11,
	minute => 15
);

$span = DateTime::Span->from_datetimes(
	start => $datetime1,
	end   => $datetime2
);


$wd_start = DateTime::Set->from_recurrence(
	recurrence => sub {
		# Tomorrow at 9 am
		$_[0]->truncate( to => 'day' )->add( days => 1, hours => 9 );
		# Add two days if it's Saturday
		$_[0]->add( days => 2) if $_[0]->day == 6;
	},
);

$wd_end = DateTime::Set->from_recurrence(
	recurrence => sub {
		# Tomorrow at 5pm
		$_[0]->truncate( to => 'day' )->add( days => 1, hours => 17 );
		# Add two days if it's Saturday
		$_[0]->add( days => 2) if $_[0]->day == 6;
	},
);

$working_hours = DateTime::SpanSet->from_sets(
	start_set => $wd_start,
	end_set => $wd_end,
);

$relevent_work_hours = $working_hours->intersection( $span );

print Dumper($relevent_work_hours->duration->deltas);