Minor aside: the language is Perl, not PERL. It isn't an acronym for anything, although there are plenty of bacronyms - "Pathologically Eclectic Rubbish Collector" is one of my favourites.
See the Perl documentation for regular expression help. A good place to start is perlre.
In reply to Re^5: Perl code to format the text file by inserting tag in blank line
by GrandFather
in thread Perl code to format the text file by inserting tag in blank line
by DAN0207
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