Just because I like to roll my own:
use strict;
use warnings;
while (<DATA>) {
chomp; print "$_ : ", validate($_), "\n";
}
BEGIN {
my @mdays = (0,31,28,31,30,31,30,31,31,30,31,30,31);
sub validate {
no warnings;
my ($year, $month, $day) = $_[0] =~ m/^(\d{4})(\d{2})(\d{2})$/
+;
my $nyear = (localtime())[5] + 1900;
##### Year range is 10 years on either side of current year
##### Also exits if m// returned nothing
return if $year < $nyear - 10 || $year > $nyear + 10;
return if $month < 1 || $month > 12;
##### Leap year conditions
if ($month == 2) {
if ($year % 4 != 0) { $mdays[2] = 28; }
elsif ($year % 400 == 0) { $mdays[2] = 29; }
elsif ($year % 100 == 0) { $mdays[2] = 28; }
else { $mdays[2] = 29; }
}
return if $day < 1 || $day > $mdays[$month];
return 1;
}
}
__DATA__
1234567
19991203
20051303
20051232
20040229
20050229
20401223