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Character Class Names.


Character Classes that are Always Supported
Character classes that are supported by Unicode Regular Expressions

Character Classes that are Always Supported

The following character class names are always supported by Boost.Regex:

Name POSIX-standard name Description
alnum Yes Any alpha-numeric character.
alpha Yes Any alphabetic character.
blank Yes Any whitespace character that is not a line separator.
cntrl Yes Any control character.
d No Any decimal digit
digit Yes Any decimal digit.
graph Yes Any graphical character.
l No Any lower case character.
lower Yes Any lower case character.
print Yes Any printable character.
punct Yes Any punctuation character.
s No Any whitespace character.
space Yes Any whitespace character.
unicode No Any extended character whose code point is above 255 in value.
u No Any upper case character.
upper Yes Any upper case character.
w No Any word character (alphanumeric characters plus the underscore).
word No Any word character (alphanumeric characters plus the underscore).
xdigit Yes Any hexadecimal digit character.

Character classes that are supported by Unicode Regular Expressions

The following character classes are only supported by Unicode Regular Expressions: that is those that use the u32regex type.  The names used are the same as those from Chapter 4 of the Unicode standard.

Short Name Long Name
C* Other
Cc Control
Cf Format
Cn Not Assigned
Co Private Use
Cs Surrogate
L* Letter
Ll Lowercase Letter
Lm Modifier Letter
Lo Other Letter
Lt Titlecase
Lu Uppercase Letter
M* Mark
Mc Spacing Combining Mark
Me Enclosing Mark
Mn Non-Spacing Mark
N* Number
Nd Decimal Digit Number
Nl Letter Number
No Other Number
P* Punctuation
Pc Connector Punctuation
Pd Dash Punctuation
Pe Close Punctuation
Pf Final Punctuation
Pi Initial Punctuation
Po Other Punctuation
Ps Open Punctuation
S* Symbol
Sc Currency Symbol
Sk Modifier Symbol
Sm Math Symbol
So Other Symbol
Z* Separator
Zl Line Separator
Zp Paragraph Separator
Zs Space Separator

Revised   10 Jan 2005 

Copyright John Maddock 2004-5

Use, modification and distribution are subject to the Boost Software License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at