Very nice example of these DateTime modules. I installed them and hope they are useful. But, it doesn't exactly figure the intersecting time of 2 sets of start, end times.

But here is a way to do it that produces output like he wanted. There are other modules besides DateTime that would provide solutions, Time::Piece (Time::Piece was first released with perl v5.9.5), Date::Parse, Time::Local, and probably others.

Either set of beg/end times could be switched, ($d1_beg and $d1_end could have been named $d2_beg, $d2_end and vice versa and this method would still be correct.

Chris 

#!/usr/bin/perl
use strict;
use warnings;
use DateTime::Format::Strptime;
use List::Util qw/ maxstr minstr /; # first released with perl v5.7.3

my $d1_beg = '2012-08-17 12:00:00';
my $d1_end = '2012-08-17 13:00:00';

my $d2_beg = '2012-08-17 09:00:00';
my $d2_end = '2012-08-17 12:30:00';

if ($d2_beg ge $d1_end or $d2_end le $d1_beg) {
    print "No common time\n";   
}
else {
    my $start = maxstr($d1_beg, $d2_beg);
    my $end   = minstr($d1_end, $d2_end);
    
    my $dt = DateTime::Format::Strptime->new(pattern => "%F %T");
    
    my @dt = map $dt->parse_datetime($_), $start, $end;
    my $dur = $dt[1]->delta_ms($dt[0])->in_units('minutes'); # duratio
+n
    
    print "$start for $dur minutes\n";
}

__END__
*** prints
2012-08-17 12:00:00 for 30 minutes

[download]

Update: There is a nice discussion here about handling durations with DateTime.

In reply to Re^2: timestamp manipulation and evaluation by Cristoforo
in thread timestamp manipulation and evaluation by jonathancnewcomb

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