| [abc] | |
| [^abc] | but a, b, or c','wordpress-https'); ?> |
| [a-z] | |
| [a-zA-Z] | |
| \s | |
| \S | |
| \d | |
| \D | |
| \w | |
| \W | |
| \b | |
| \B | |
| | | |
| () | |
| ^ | |
| $ |
| {n,m} | n times but no more than m times','wordpress-https'); ?> |
| {n,} | n or more times','wordpress-https'); ?> |
| {n} | n occurrences of the previous item','wordpress-https'); ?> |
| ? | |
| + | |
| * |