@@ -62,40 +61,46 @@ syntax. \a alarm, that is, the BEL character (hex 07) \cx "control-x", where x is any ASCII character \e escape (hex 1B) - \f formfeed (hex 0C) + \f form feed (hex 0C) \n newline (hex 0A) \r carriage return (hex 0D) \t tab (hex 09) + \0dd character with octal code 0dd \ddd character with octal code ddd, or backreference + \o{ddd..} character with octal code ddd.. \xhh character with hex code hh \x{hhh..} character with hex code hhh.. - + +Note that \0dd is always an octal code, and that \8 and \9 are the literal +characters "8" and "9".
. any character except newline;
in dotall mode, any character whatsoever
- \C one byte, even in UTF-8 mode (best avoided)
+ \C one data unit, even in UTF mode (best avoided)
\d a decimal digit
\D a character that is not a decimal digit
- \h a horizontal whitespace character
- \H a character that is not a horizontal whitespace character
+ \h a horizontal white space character
+ \H a character that is not a horizontal white space character
\N a character that is not a newline
\p{xx} a character with the xx property
\P{xx} a character without the xx property
\R a newline sequence
- \s a whitespace character
- \S a character that is not a whitespace character
- \v a vertical whitespace character
- \V a character that is not a vertical whitespace character
+ \s a white space character
+ \S a character that is not a white space character
+ \v a vertical white space character
+ \V a character that is not a vertical white space character
\w a "word" character
\W a "non-word" character
- \X an extended Unicode sequence
+ \X a Unicode extended grapheme cluster
-In PCRE, by default, \d, \D, \s, \S, \w, and \W recognize only ASCII
-characters, even in UTF-8 mode. However, this can be changed by setting the
-PCRE_UCP option.
+By default, \d, \s, and \w match only ASCII characters, even in UTF-8 mode
+or in the 16- bit and 32-bit libraries. However, if locale-specific matching is
+happening, \s and \w may also match characters with code points in the range
+128-255. If the PCRE_UCP option is set, the behaviour of these escape sequences
+is changed to use Unicode properties and they match many more characters.
@@ -151,9 +156,13 @@ PCRE_UCP option.
Xan Alphanumeric: union of properties L and N Xps POSIX space: property Z or tab, NL, VT, FF, CR - Xsp Perl space: property Z or tab, NL, FF, CR + Xsp Perl space: property Z or tab, NL, VT, FF, CR + Xuc Univerally-named character: one that can be + represented by a Universal Character Name Xwd Perl word: property Xan or underscore -+ +Perl and POSIX space are now the same. Perl added VT to its space character set +at release 5.18 and PCRE changed at release 8.34.
@@ -162,13 +171,16 @@ Armenian, Avestan, Balinese, Bamum, +Batak, Bengali, Bopomofo, +Brahmi, Braille, Buginese, Buhid, Canadian_Aboriginal, Carian, +Chakma, Cham, Cherokee, Common, @@ -211,7 +223,11 @@ Lisu, Lycian, Lydian, Malayalam, +Mandaic, Meetei_Mayek, +Meroitic_Cursive, +Meroitic_Hieroglyphs, +Miao, Mongolian, Myanmar, New_Tai_Lue, @@ -230,8 +246,10 @@ Rejang, Runic, Samaritan, Saurashtra, +Sharada, Shavian, Sinhala, +Sora_Sompeng, Sundanese, Syloti_Nagri, Syriac, @@ -240,6 +258,7 @@ Tagbanwa, Tai_Le, Tai_Tham, Tai_Viet, +Takri, Tamil, Telugu, Thaana, @@ -269,7 +288,7 @@ Yi. lower lower case letter print printing, including space punct printing, excluding alphanumeric - space whitespace + space white space upper upper case letter word same as \w xdigit hexadecimal digit @@ -366,10 +385,17 @@ but some of them use Unicode properties if PCRE_UCP is The following are recognized only at the start of a pattern or after one of the newline-setting options with similar syntax:
+ (*LIMIT_MATCH=d) set the match limit to d (decimal number) + (*LIMIT_RECURSION=d) set the recursion limit to d (decimal number) (*NO_START_OPT) no start-match optimization (PCRE_NO_START_OPTIMIZE) - (*UTF8) set UTF-8 mode (PCRE_UTF8) + (*UTF8) set UTF-8 mode: 8-bit library (PCRE_UTF8) + (*UTF16) set UTF-16 mode: 16-bit library (PCRE_UTF16) + (*UTF32) set UTF-32 mode: 32-bit library (PCRE_UTF32) + (*UTF) set appropriate UTF mode for the library in use (*UCP) set PCRE_UCP (use Unicode properties for \d etc) -+ +Note that LIMIT_MATCH and LIMIT_RECURSION can only reduce the value of the +limits set by the caller of pcre_exec(), not increase them.
@@ -439,6 +465,7 @@ The following act immediately they are reached:
(*ACCEPT) force successful match (*FAIL) force backtrack; synonym (*F) + (*MARK:NAME) set name to be passed back; synonym (*:NAME)The following act only when a subsequent match failure causes a backtrack to reach them. They all force a match failure, but they differ in what happens @@ -447,14 +474,18 @@ pattern is not anchored.
(*COMMIT) overall failure, no advance of starting point (*PRUNE) advance to next starting character - (*SKIP) advance start to current matching position + (*PRUNE:NAME) equivalent to (*MARK:NAME)(*PRUNE) + (*SKIP) advance to current matching position + (*SKIP:NAME) advance to position corresponding to an earlier + (*MARK:NAME); if not found, the (*SKIP) is ignored (*THEN) local failure, backtrack to next alternation + (*THEN:NAME) equivalent to (*MARK:NAME)(*THEN)
These are recognized only at the very start of the pattern or after a -(*BSR_...) or (*UTF8) or (*UCP) option. +(*BSR_...), (*UTF8), (*UTF16), (*UTF32) or (*UCP) option.
(*CR) carriage return only (*LF) linefeed only @@ -466,7 +497,7 @@ These are recognized only at the very start of the pat
WHAT \R MATCHES
These are recognized only at the very start of the pattern or after a -(*...) option that sets the newline convention or UTF-8 or UCP mode. +(*...) option that sets the newline convention or a UTF or UCP mode.
(*BSR_ANYCRLF) CR, LF, or CRLF (*BSR_UNICODE) any Unicode newline sequence @@ -495,9 +526,9 @@ Cambridge CB2 3QH, England.
REVISION
-Last updated: 21 November 2010 +Last updated: 12 November 2013
-Copyright © 1997-2010 University of Cambridge. +Copyright © 1997-2013 University of Cambridge.
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