http://www.perlmonks.org?node_id=1015464


in reply to regexp wizardry needed

Tested under 5.8 through 5.14: 

>perl -wMstrict -le
"my $currentyear = '2013';
 my $lines2 = ' PERIOD 13 OCT 06 OCT';
 ;;
 $lines2 =~ s{ (\d\d) \s ([[:upper:]]{3} (?! \S)) }
             {\u\L$2 $1, $currentyear}xmsg;
 print qq{$lines2};
"
 PERIOD Oct 13, 2013 Oct 06, 2013

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