Shorthand expressions
The following expressions are shorthand for longer or more complex regular expressions:
Expression | Purpose | Example | Match |
|---|---|---|---|
[:alpha:] | Matches must consist of letters. | [:alpha:]8,16 | aBcmGLeEhhi |
[:digit:] | Matches must consist of digits. [:digit:] is equivalent to [:d:] and \ d. | [[:digit:]]+ | 2962954576 |
[:upper:] | Matches must consist of uppercase characters. | [[:upper:][:digit:]]+ | 9DDD4MLAG13 |
[:alnum:] | Matches must be alphanumeric. [:alnum:] is short hand for [a-zA-Z0-9] in the ascii character set, but the use of [:alnum:] is preferred for compatibility with other languages and character sets. | [:alnum:]7[^[:digit:]] | a3dM9DD+ |