[Perl] Date연산

1.pl

#!/usr/bin/perl

use DateTime;
use strict;
use warnings;

my $start_date = DateTime->new(
    year=>1901,
    month=>1,
    day=>1,
    
);

my $end_date = DateTime->new(
    year=>2000,
    month=>12,
    day=>31,
    
);

DateTime->compare($start_date, $end_date); #비교구문
$start_date->day == 1; #일
$start_date->day_of_week == 7; #요일, 7이 일요일
$start_date->add(days=>1); #연산