Thanks for sharing. Here is what i came up with. Instead of setting a limit at 20 records, this version will keep adding new files until the input file is exhausted.

I did use one regex to read the line that tells how many records to expect. I also took the liberty of changing the names of the output files with sprintf and a different prefix than the original file (just so i could delete my mistakes easier :D). 

use strict;

open(IN,'old_file.txt') or die;

my $i = 1;
while (<IN>) {
   if (/^(\d+)\s*$/) {
      open(OUT,'>new_file'.sprintf("%02d",$i++).'.txt') or die;
      do { $_ = <IN>; print OUT; } for (1..$1);
   }
}

[download]

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

In reply to (jeffa) Re: To regex or not to regex by jeffa
in thread To regex or not to regex by mndoci

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