use strict;
my $str = '12d m1 M1 "kia ita-_//()/&%),.+=/7\\lia" *2 Y*G "stan_the man" -- "\\"fef 1234" \\"fef 1234\\" "asdf" "as\\"asdf" as\\"df asdf';
my $regex = qr/(\w|!|#|\$|%|&|/|\\|\(|\)|=|_|-|\+|\*|,|\.|(?<=\\)"")+|(?<!\\)""(\w|!|#|\$|%|&|/|\\|\(|\)|=|_|-|\+|\*|,|\.|(?<=\\)""|\s)+(?<!\\)""/ip;
my $subst = '\\n$0';
my $result = $str =~ s/$regex/$subst/rg;
print "The result of the substitution is' $result\n";
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Perl, please visit: http://perldoc.perl.org/perlre.html