Revision: 575
http://vcs.pcre.org/viewvc?view=rev&revision=575
Author: ph10
Date: 2010-11-21 12:55:42 +0000 (Sun, 21 Nov 2010)
Log Message:
-----------
Documentation clarification.
Modified Paths:
--------------
code/trunk/doc/pcrepattern.3
Modified: code/trunk/doc/pcrepattern.3
===================================================================
--- code/trunk/doc/pcrepattern.3 2010-11-20 17:47:27 UTC (rev 574)
+++ code/trunk/doc/pcrepattern.3 2010-11-21 12:55:42 UTC (rev 575)
@@ -1052,12 +1052,28 @@
characters with values greater than 128 only when it is compiled with Unicode
property support.
.P
-The character types \ed, \eD, \eh, \eH, \ep, \eP, \es, \eS, \ev, \eV, \ew, and
-\eW may also appear in a character class, and add the characters that they
-match to the class. For example, [\edABCDEF] matches any hexadecimal digit. A
-circumflex can conveniently be used with the upper case character types to
+The character escape sequences \ed, \eD, \eh, \eH, \ep, \eP, \es, \eS, \ev,
+\eV, \ew, and \eW may appear in a character class, and add the characters that
+they match to the class. For example, [\edABCDEF] matches any hexadecimal
+digit. In UTF-8 mode, the PCRE_UCP option affects the meanings of \ed, \es, \ew
+and their upper case partners, just as it does when they appear outside a
+character class, as described in the section entitled
+.\" HTML <a href="#genericchartypes">
+.\" </a>
+"Generic character types"
+.\"
+above. The escape sequence \eb has a different meaning inside a character
+class; it matches the backspace character. The sequences \eB, \eN, \eR, and \eX
+are not special inside a character class. Like any other unrecognized escape
+sequences, they are treated as the literal characters "B", "N", "R", and "X" by
+default, but cause an error if the PCRE_EXTRA option is set.
+.P
+A circumflex can conveniently be used with the upper case character types to
specify a more restricted set of characters than the matching lower case type.
-For example, the class [^\eW_] matches any letter or digit, but not underscore.
+For example, the class [^\eW_] matches any letter or digit, but not underscore,
+whereas [\ew] includes underscore. A positive character class should be read as
+"something OR something OR ..." and a negative class as "NOT something AND NOT
+something AND NOT ...".
.P
The only metacharacters that are recognized in character classes are backslash,
hyphen (only where it can be interpreted as specifying a range), circumflex
@@ -2726,6 +2742,6 @@
.rs
.sp
.nf
-Last updated: 20 November 2010
+Last updated: 21 November 2010
Copyright (c) 1997-2010 University of Cambridge.
.fi
