Re: DateTime::Span - a span created with before has the same range as a span created with end

[Dave Rolsky]

On Tue, 31 Mar 2009, Terrence Brannon wrote:

Intuitively, it would seem that specifying the 'before' of a datetime
span using the end option of the ->from_datetimes() constructor would
yield a range that is 1 second (1 nanosecond?) earlier than the actual
date supplied.
But as it is stands, the end of a range specified using the 'before'
option is the same as one specified using the 'end' option:


use strict; use warnings;

use DateTime;
use DateTime::Span;


my $dt1 = DateTime->new( year => 2002, month => 3, day => 11 );
my $dt2 = DateTime->new( year => 2003, month => 4, day => 12 );

my $span  = DateTime::Span->from_datetimes( start => $dt1, before => $dt2 );


warn 'start: ' . $span->start . ' end: ' .  $span->end;

my $span  = DateTime::Span->from_datetimes( start => $dt1, end => $dt2 );

warn 'start: ' . $span->start . ' end: ' .  $span->end;  ### same
output as with 'before'

_But_ if you check whether the span _includes_ its end date you get a 
different answer:

  use strict;
  use warnings;

  use DateTime;
  use DateTime::Span;

  my $dt1 = DateTime->new( year => 2002, month => 3, day => 11 );
  my $dt2 = DateTime->new( year => 2003, month => 4, day => 12 );

  my $span1  = DateTime::Span->from_datetimes( start => $dt1, before => $dt2 );
  my $span2  = DateTime::Span->from_datetimes( start => $dt1, end => $dt2 );


  for my $span ($span1, $span2 )
  {
      warn 'start: ' . $span->start . ' end: ' .  $span->end;
      warn 'includes end? ' . ( $span->contains($dt2) ? 'yes' : 'no' ) . "\n";
  }



-dave

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