use 5.010;
use strict;
use warnings FATAL => qw(all);
use DateTimeX::Auto qw(:auto);

{
    # slightly evil, but works...
    package DateTime;
    use overload '~~', sub { $_[0]->ymd eq $_[1]->ymd }
}

my $not_business_days = [
    sub { $_[0]->day_abbr =~ /^S/ },  # weekends
    qw(
        2012-01-02
        2012-04-06
        2012-04-09
        2012-05-07
        2012-06-04
        2012-06-05
        2012-08-27
        2012-12-25
        2012-12-26
    ),
];

my $date = '2012-01-01';
my $end  = '2013-01-01';

while ($date < $end)
{
    say $date->ymd("")
        unless $date ~~ $not_business_days;
    $date->add(days => 1);
}
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