Here’s a quick cheatsheet of the metacharacters used in regular expressions.
Metacharacter | Name | Matches |
---|---|---|
. | dot | any one character |
[ ... ] | character class | any character listed |
[^...] | negated character class | any character not listed |
^ | caret | the position at the start of the line |
$ | dollar | the position at the end of the line |
\< | backslash less-than | the position at the start of the word |
\> | backslash greater-than | the position at the end of the word |
| | or, bar | matches either expression it separates |
( ... ) | parentheses | used to limit scope of | |
? | question mark | one allowed; none required ("one optional") |
* | asterisk | unlimited allowed; none required ("any amount OK") |
+ | plus | unlimited allowed; one required ("at least one") |
\1, \2, ... | back reference | matches text previously matched within first, second, etc., set of parentheses |
\ | backslash | escape a metacharacter to match literally |
{ ... } | braces | Interval; counting quantifier; specify number of matches |