c:\@Work\Perl\monks>perl -wMstrict -le
"use 5.010;
 ;;
 my $data = '1|2|3|4|5|6|7|8|9|a|b|c|d|e|f|g|h|i';
 print qq{'$data'};
 ;;
 local our $n;
 $data =~ s{ \| (?(?{ ++$n < 10 || $n > 12 }) (*FAIL)) }{ pipe }xmsg;
 print qq{'$data'};
"
'1|2|3|4|5|6|7|8|9|a|b|c|d|e|f|g|h|i'
'1|2|3|4|5|6|7|8|9|a pipe b pipe c pipe d|e|f|g|h|i'