A Tie::File solution would look like the following, but it would be much more expensive than the following: 
my $found = 0;
while (<$fh>) {
   if (match()) {
      $found = $.;
      last;
   }
}

if ($found) {
   seek($fh, $found, SEEK_SET);
   open(my $fh_tmp, '<', ...) or die;
   while (<$fh>) {
      transform();
      print $fh_tmp $_;
   }
   replace_original_with_tmp();
}

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In reply to Re^2: redo entire loop by ikegami
in thread redo entire loop by Anonymous Monk

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