$something =~ / ^        # start at beginning of the string 
                (        # capture var $1 
                  (      # capture var $2 
                    -*   # zero, one, or more '-' 
                  )      # end capture var $2 
                  |      # alternative pattern if -* fails 
                  (      # capture var $2, again 
                    \s*  # zero, one, or more white space 
                  )      # end capture var $2 
                )        # end capture var $1 
                $ /x;    # end of string 
Code
 
It captures in $1 and $2 blank lines, lines full of '-' and lines with not but white space. 
 
__END__ 
 
I love Perl; it's the only language where you can bless your thingy. 
 
Perl documentation is available at perldoc.perl.org.  The list of standard modules and pragmatics is available in perlmodlib. 
 
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