use File::Slurp;
 
$_ = read_file($ARGV[0] // $0);
s/<(CR|LF)>/\\<$1\\>/g; # "Escape" existing
s/\x0d/<CR>/g, s/\x0a/<LF>/g;
s/((?:<CR>)?<LF>)/$1\n/g; # Add real line breaks
say;