Oops! 
while (<IN>) {
   s{(<tgroup cols="(.*?)">)}{
      "$1\n" .
      join('', map { "<colspec colnum='$_' colname='$_'/>\n" } 1..$2)
   }eg;
   print OUT;
}

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In reply to Re^3: for loop by ikegami
in thread for loop by texuser74

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