Boost-Supported RegEx Character Classes
Boost.Regex always supports these class names:
Name | POSIX-Standard Name | Description | Example |
|---|---|---|---|
[:alnum:] | Yes | Alpha-numeric Characters | [A-Za-z0-9] |
[:alpha:] | Yes | Alphabetic Characters | [A-Za-z] |
[:blank:] | Yes | Whitespace characters that are not line separators. | space or tab |
[:cntrl:] | Yes | Control Characters | Any character not part of the character class: [:upper:], [:lower:], [:alpha:], [:digit:], [:punct:], [:graph:], [:print:], [:xdigit:] |
[:d:] | No | Decimal Digits | [0–9] |
[:digit:] | Yes | Decimal Digits | [0–9] |
[:graph:] | Yes | Characters with graphic representation. | [A–Z][a–z][0–9][:punct:] |
[:l:] | No | Lowercase Characters | [a–z] |
[:lower:] | Yes | Lowercase Characters | [a–z] |
[:print:] | Yes | Characters that display when printed. | [:graph:] and space |
[:punct:] | Yes | Punctuation Characters | ! ' # S % & ' ( ) * + , - . / : ; < = > ? @ [ / ] ^ _ { | } ~ |
[:s:] | No | Whitespace Characters | tab, new line, vertical tab, form feed, carriage return, space |
[:space:] | Yes | Whitespace Characters | tab, new line, vertical tab, form feed, carriage return, space |
[:unicode:] | No | Extended characters whose code point value is above 255. | Any character with code point above 255. |
[:u:] | No | Uppercase Characters | [A–Z] |
[:upper:] | Yes | Uppercase Characters | [A–Z] |
[:w:] | No | Alphanumeric characters and underscore. | [A-Za-z0-9_] |
[:word:] | No | Alphanumeric characters and underscore. | [A-Za-z0-9_] |
[:xdigit:] | Yes | Hexadecimal Digit Characters | [A-Fa-f0-9] |