okay, I'm cheating: 
#!/usr/bin/perl

use strict;
use warnings;

while(<DATA>) {
  chomp(my $is_valid = $_);
  print $is_valid, "\n" if grep {/^$is_valid$/} (1950..2050);
}

__DATA__
1949
1950
1951
1999
2000
2001
2010
2049
2050
2051
2102
22102
19534
19080
20010

[download]
best regards, Ronnie

In reply to Re: Matching date range with pure regex by Anonymous Monk
in thread Matching date range with pure regex by BUU

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