Use the metacharacters described in the table below when performing searches or creating rules:
| Metacharacter | Description |
|---|---|
| ^ | Anchors match to the beginning of a line or string |
| $ | Anchors match to the end of a line or string |
| abc | Matches all of a, b, and c in order |
| fee|fie|foe | Matches one of fee, fie, or foe |
| ^(?!fee|fie|foe) | Matches anything other than fee, fie, or foe |
| . | Matches any character except newline |
| x? | Matches 0 or 1 occurrences of x (x can be any character) |
| x* | Matches 0 or more occurrences of x |
| x+ | Matches 1 or more occurrences of x |
| x{m,n} | Matches at least m occurrences of x but no more than n |
| [a-z0-9] | Matches any single character of set |
| [^a-z0-9] | Matches any single character not in set |
| \d | Matches a digit, same as [0-9] |
| \D | Matches a non-digit, same as [^0-9] |
| \w | Matches an alphanumeric (word) character [a-zA-Z0-9_] |
| \W | Matches a non-word character [^a-zA-Z0-9_] |
| \s | Matches a whitespace character (space, tab, newline…) |
| \S | Matches a non-whitespace character |
| \metachar | Treat metacharacter as ordinary character; for example, \* matches the * character |
| (abc) | Remembers the match for later backreferences |
| \1 | Matches whatever first set of parens matched |
| \2 | Matches whatever second set of parens matched |
| \3 | and so on… |
| \b | Matches a word boundary (outside [] only) |
| \B | Matches a non-word boundary |
Tip: Use the ^ and $ metacharacters around values that may be part of other values. For example, a value of 5 without anchors will also match with 15, 250, etc. To prevent it from matching with other values, place anchors around it: ^5$.