I was scouring through SO answers and found that the solution that most gave for replacing multiple spaces is:
$new_str = preg_replace("/\s+/", " ", $str);
But in many cases the white space characters include UTF characters that include line feed, form feed, carriage return, non-breaking space, etc. This wiki
describes that UTF defines twenty-five characters defined as whitespace.
So how do we replace all these characters as well using regular expressions?