perl -e 'print "match\n" if "foo\n" =~ /.+$/'  # ok #
perl -e 'print "match\n" if "foo\n" =~ /.+\z/'
perl -e 'print "match\n" if "foo\n" =~ /.+\Z/'  # ok #
perl -e 'print "match\n" if "foo\n\n\n" =~ /.+\Z/'     
perl -e 'print "match\n" if "foo\n\n\n" =~ /.+\z/'    
perl -e 'print "match\n" if "foo\n\n\n" =~ /.+$/'
perl -e 'print "match\n" if "foo\n\n\n" =~ /.+$/m'  # ok #
perl -e 'print "match\n" if "foo\n\n\n" =~ /.+\z/m'
perl -e 'print "match\n" if "foo\n\n\n" =~ /.+\Z/m'
perl -e 'print "match\n" if "foo\n\n\n" =~ /.+\Z/s'  # ok #
perl -e 'print "match\n" if "foo\n\n\n" =~ /.+\z/s'  # ok #
perl -e 'print "match\n" if "foo\n\n\n" =~ /.+$/s'  # ok #