sub get_date_perl2 {

    $_[0] =~ m/[|](\d{4})(\d{4})[|]/;
    return $2.$1;
}


##</code><code>##

Benchmark: timing 50 iterations of Inline, Ovidian, Perl, Perl2...
    Inline: 19 wallclock secs (18.72 usr +  0.01 sys = 18.73 CPU) @  2.67/s
   Ovidian: 17 wallclock secs (17.08 usr +  0.08 sys = 17.16 CPU) @  2.91/s
      Perl: 25 wallclock secs (24.48 usr +  0.08 sys = 24.56 CPU) @  2.04/s
     Perl2: 24 wallclock secs (23.36 usr +  0.14 sys = 23.50 CPU) @  2.13/s

          Rate    Perl   Perl2  Inline Ovidian
Perl    2.04/s      --     -4%    -24%    -30%
Perl2   2.13/s      5%      --    -20%    -27%
Inline  2.67/s     31%     25%      --     -8%
Ovidian 2.91/s     43%     37%      9%      --