use strict;
use Date::Tie;
tie my %dt, 'Date::Tie';
my @a;
for (1..7) 
{
    push @a, join('-', $dt{year}, $dt{month}, $dt{day});
    $dt{day}--;
}
my $re = join('|', @a);

for ( qw( 2003-08-25 2003-08-20 2003-08-27 2003-08-15 ) )
{
    print "$_ is ";
    print "not " unless /$re/; 
    print "in last 6 days\n";
}

# 2003-08-25 is in last 6 days
# 2003-08-20 is in last 6 days
# 2003-08-27 is not in last 6 days
# 2003-08-15 is not in last 6 days