Include RE2 library

third_party/re2/doc/syntax.txt

Index: third_party/re2/doc/syntax.txt
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+RE2 regular expression syntax reference
+-------------------------­-------­-----
+
+Single characters:
+.	any character, including newline (s=true)
+[xyz]	character class
+[^xyz]	negated character class
+\d	Perl character class
+\D	negated Perl character class
+[:alpha:]	ASCII character class
+[:^alpha:]	negated ASCII character class
+\pN	Unicode character class (one-letter name)
+\p{Greek}	Unicode character class
+\PN	negated Unicode character class (one-letter name)
+\P{Greek}	negated Unicode character class
+
+Composites:
+xy	«x» followed by «y»
+x|y	«x» or «y» (prefer «x»)
+
+Repetitions:
+x*	zero or more «x», prefer more
+x+	one or more «x», prefer more
+x?	zero or one «x», prefer one
+x{n,m}	«n» or «n»+1 or ... or «m» «x», prefer more
+x{n,}	«n» or more «x», prefer more
+x{n}	exactly «n» «x»
+x*?	zero or more «x», prefer fewer
+x+?	one or more «x», prefer fewer
+x??	zero or one «x», prefer zero
+x{n,m}?	«n» or «n»+1 or ... or «m» «x», prefer fewer
+x{n,}?	«n» or more «x», prefer fewer
+x{n}?	exactly «n» «x»
+x{}	(== x*) NOT SUPPORTED vim
+x{-}	(== x*?) NOT SUPPORTED vim
+x{-n}	(== x{n}?) NOT SUPPORTED vim
+x=	(== x?) NOT SUPPORTED vim
+
+Possessive repetitions:
+x*+	zero or more «x», possessive NOT SUPPORTED
+x++	one or more «x», possessive NOT SUPPORTED
+x?+	zero or one «x», possessive NOT SUPPORTED
+x{n,m}+	«n» or ... or «m» «x», possessive NOT SUPPORTED
+x{n,}+	«n» or more «x», possessive NOT SUPPORTED
+x{n}+	exactly «n» «x», possessive NOT SUPPORTED
+
+Grouping:
+(re)	numbered capturing group
+(?P<name>re)	named & numbered capturing group
+(?<name>re)	named & numbered capturing group NOT SUPPORTED
+(?'name're)	named & numbered capturing group NOT SUPPORTED
+(?:re)	non-capturing group
+(?flags)	set flags within current group; non-capturing
+(?flags:re)	set flags during re; non-capturing
+(?#text)	comment NOT SUPPORTED
+(?|x|y|z)	branch numbering reset NOT SUPPORTED
+(?>re)	possessive match of «re» NOT SUPPORTED
+re@>	possessive match of «re» NOT SUPPORTED vim
+%(re)	non-capturing group NOT SUPPORTED vim
+
+Flags:
+i	case-insensitive (default false)
+m	multi-line mode: ^ and $ match begin/end line in addition to begin/end text (default false)
+s	let «.» match «\n» (default false)
+U	ungreedy: swap meaning of «x*» and «x*?», «x+» and «x+?», etc (default false)
+Flag syntax is «xyz» (set) or «-xyz» (clear) or «xy-z» (set «xy», clear «z»).
+
+Empty strings:
+^	at beginning of text or line («m»=true)
+$	at end of text (like «\z» not «\Z») or line («m»=true)
+\A	at beginning of text
+\b	at word boundary («\w» on one side and «\W», «\A», or «\z» on the other)
+\B	not a word boundary
+\G	at beginning of subtext being searched NOT SUPPORTED pcre
+\G	at end of last match NOT SUPPORTED perl
+\Z	at end of text, or before newline at end of text NOT SUPPORTED
+\z	at end of text
+(?=re)	before text matching «re» NOT SUPPORTED
+(?!re)	before text not matching «re» NOT SUPPORTED
+(?<=re)	after text matching «re» NOT SUPPORTED
+(?<!re)	after text not matching «re» NOT SUPPORTED
+re&	before text matching «re» NOT SUPPORTED vim
+re@=	before text matching «re» NOT SUPPORTED vim
+re@!	before text not matching «re» NOT SUPPORTED vim
+re@<=	after text matching «re» NOT SUPPORTED vim
+re@<!	after text not matching «re» NOT SUPPORTED vim
+\zs	sets start of match (= \K) NOT SUPPORTED vim
+\ze	sets end of match NOT SUPPORTED vim
+\%^	beginning of file NOT SUPPORTED vim
+\%$	end of file NOT SUPPORTED vim
+\%V	on screen NOT SUPPORTED vim
+\%#	cursor position NOT SUPPORTED vim
+\%'m	mark «m» position NOT SUPPORTED vim
+\%23l	in line 23 NOT SUPPORTED vim
+\%23c	in column 23 NOT SUPPORTED vim
+\%23v	in virtual column 23 NOT SUPPORTED vim
+
+Escape sequences:
+\a	bell (== \007)
+\f	form feed (== \014)
+\t	horizontal tab (== \011)
+\n	newline (== \012)
+\r	carriage return (== \015)
+\v	vertical tab character (== \013)
+\*	literal «*», for any punctuation character «*»
+\123	octal character code (up to three digits)
+\x7F	hex character code (exactly two digits)
+\x{10FFFF}	hex character code
+\C	match a single byte even in UTF-8 mode
+\Q...\E	literal text «...» even if «...» has punctuation
+
+\1	backreference NOT SUPPORTED
+\b	backspace NOT SUPPORTED (use «\010»)
+\cK	control char ^K NOT SUPPORTED (use «\001» etc)
+\e	escape NOT SUPPORTED (use «\033»)
+\g1	backreference NOT SUPPORTED
+\g{1}	backreference NOT SUPPORTED
+\g{+1}	backreference NOT SUPPORTED
+\g{-1}	backreference NOT SUPPORTED
+\g{name}	named backreference NOT SUPPORTED
+\g<name>	subroutine call NOT SUPPORTED
+\g'name'	subroutine call NOT SUPPORTED
+\k<name>	named backreference NOT SUPPORTED
+\k'name'	named backreference NOT SUPPORTED
+\lX	lowercase «X» NOT SUPPORTED
+\ux	uppercase «x» NOT SUPPORTED
+\L...\E	lowercase text «...» NOT SUPPORTED
+\K	reset beginning of «$0» NOT SUPPORTED
+\N{name}	named Unicode character NOT SUPPORTED
+\R	line break NOT SUPPORTED
+\U...\E	upper case text «...» NOT SUPPORTED
+\X	extended Unicode sequence NOT SUPPORTED
+
+\%d123	decimal character 123 NOT SUPPORTED vim
+\%xFF	hex character FF NOT SUPPORTED vim
+\%o123	octal character 123 NOT SUPPORTED vim
+\%u1234	Unicode character 0x1234 NOT SUPPORTED vim
+\%U12345678	Unicode character 0x12345678 NOT SUPPORTED vim
+
+Character class elements:
+x	single character
+A-Z	character range (inclusive)
+\d	Perl character class
+[:foo:]	ASCII character class «foo»
+\p{Foo}	Unicode character class «Foo»
+\pF	Unicode character class «F» (one-letter name)
+
+Named character classes as character class elements:
+[\d]	digits (== \d)
+[^\d]	not digits (== \D)
+[\D]	not digits (== \D)
+[^\D]	not not digits (== \d)
+[[:name:]]	named ASCII class inside character class (== [:name:])
+[^[:name:]]	named ASCII class inside negated character class (== [:^name:])
+[\p{Name}]	named Unicode property inside character class (== \p{Name})
+[^\p{Name}]	named Unicode property inside negated character class (== \P{Name})
+
+Perl character classes:
+\d	digits (== [0-9])
+\D	not digits (== [^0-9])
+\s	whitespace (== [\t\n\f\r ])
+\S	not whitespace (== [^\t\n\f\r ])
+\w	word characters (== [0-9A-Za-z_])
+\W	not word characters (== [^0-9A-Za-z_])
+
+\h	horizontal space NOT SUPPORTED
+\H	not horizontal space NOT SUPPORTED
+\v	vertical space NOT SUPPORTED
+\V	not vertical space NOT SUPPORTED
+
+ASCII character classes:
+[:alnum:]	alphanumeric (== [0-9A-Za-z])
+[:alpha:]	alphabetic (== [A-Za-z])
+[:ascii:]	ASCII (== [\x00-\x7F])
+[:blank:]	blank (== [\t ])
+[:cntrl:]	control (== [\x00-\x1F\x7F])
+[:digit:]	digits (== [0-9])
+[:graph:]	graphical (== [!-~] == [A-Za-z0-9!"#$%&'()*+,\-./:;<=>?@[\\\]^_`{|}~])
+[:lower:]	lower case (== [a-z])
+[:print:]	printable (== [ -~] == [ [:graph:]])
+[:punct:]	punctuation (== [!-/:-@[-`{-~])
+[:space:]	whitespace (== [\t\n\v\f\r ])
+[:upper:]	upper case (== [A-Z])
+[:word:]	word characters (== [0-9A-Za-z_])
+[:xdigit:]	hex digit (== [0-9A-Fa-f])
+
+Unicode character class names--general category:
+C	other
+Cc	control
+Cf	format
+Cn	unassigned code points NOT SUPPORTED
+Co	private use
+Cs	surrogate
+L	letter
+LC	cased letter NOT SUPPORTED
+L&	cased letter NOT SUPPORTED
+Ll	lowercase letter
+Lm	modifier letter
+Lo	other letter
+Lt	titlecase letter
+Lu	uppercase letter
+M	mark
+Mc	spacing mark
+Me	enclosing mark
+Mn	non-spacing mark
+N	number
+Nd	decimal 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
+
+Unicode character class names--scripts:
+Arabic	Arabic
+Armenian	Armenian
+Balinese	Balinese
+Bengali	Bengali
+Bopomofo	Bopomofo
+Braille	Braille
+Buginese	Buginese
+Buhid	Buhid
+Canadian_Aboriginal	Canadian Aboriginal
+Carian	Carian
+Cham	Cham
+Cherokee	Cherokee
+Common	characters not specific to one script
+Coptic	Coptic
+Cuneiform	Cuneiform
+Cypriot	Cypriot
+Cyrillic	Cyrillic
+Deseret	Deseret
+Devanagari	Devanagari
+Ethiopic	Ethiopic
+Georgian	Georgian
+Glagolitic	Glagolitic
+Gothic	Gothic
+Greek	Greek
+Gujarati	Gujarati
+Gurmukhi	Gurmukhi
+Han	Han
+Hangul	Hangul
+Hanunoo	Hanunoo
+Hebrew	Hebrew
+Hiragana	Hiragana
+Inherited	inherit script from previous character
+Kannada	Kannada
+Katakana	Katakana
+Kayah_Li	Kayah Li
+Kharoshthi	Kharoshthi
+Khmer	Khmer
+Lao	Lao
+Latin	Latin
+Lepcha	Lepcha
+Limbu	Limbu
+Linear_B	Linear B
+Lycian	Lycian
+Lydian	Lydian
+Malayalam	Malayalam
+Mongolian	Mongolian
+Myanmar	Myanmar
+New_Tai_Lue	New Tai Lue (aka Simplified Tai Lue)
+Nko	Nko
+Ogham	Ogham
+Ol_Chiki	Ol Chiki
+Old_Italic	Old Italic
+Old_Persian	Old Persian
+Oriya	Oriya
+Osmanya	Osmanya
+Phags_Pa	'Phags Pa
+Phoenician	Phoenician
+Rejang	Rejang
+Runic	Runic
+Saurashtra	Saurashtra
+Shavian	Shavian
+Sinhala	Sinhala
+Sundanese	Sundanese
+Syloti_Nagri	Syloti Nagri
+Syriac	Syriac
+Tagalog	Tagalog
+Tagbanwa	Tagbanwa
+Tai_Le	Tai Le
+Tamil	Tamil
+Telugu	Telugu
+Thaana	Thaana
+Thai	Thai
+Tibetan	Tibetan
+Tifinagh	Tifinagh
+Ugaritic	Ugaritic
+Vai	Vai
+Yi	Yi
+
+Vim character classes:
+\i	identifier character NOT SUPPORTED vim
+\I	«\i» except digits NOT SUPPORTED vim
+\k	keyword character NOT SUPPORTED vim
+\K	«\k» except digits NOT SUPPORTED vim
+\f	file name character NOT SUPPORTED vim
+\F	«\f» except digits NOT SUPPORTED vim
+\p	printable character NOT SUPPORTED vim
+\P	«\p» except digits NOT SUPPORTED vim
+\s	whitespace character (== [ \t]) NOT SUPPORTED vim
+\S	non-white space character (== [^ \t]) NOT SUPPORTED vim
+\d	digits (== [0-9]) vim
+\D	not «\d» vim
+\x	hex digits (== [0-9A-Fa-f]) NOT SUPPORTED vim
+\X	not «\x» NOT SUPPORTED vim
+\o	octal digits (== [0-7]) NOT SUPPORTED vim
+\O	not «\o» NOT SUPPORTED vim
+\w	word character vim
+\W	not «\w» vim
+\h	head of word character NOT SUPPORTED vim
+\H	not «\h» NOT SUPPORTED vim
+\a	alphabetic NOT SUPPORTED vim
+\A	not «\a» NOT SUPPORTED vim
+\l	lowercase NOT SUPPORTED vim
+\L	not lowercase NOT SUPPORTED vim
+\u	uppercase NOT SUPPORTED vim
+\U	not uppercase NOT SUPPORTED vim
+\_x	«\x» plus newline, for any «x» NOT SUPPORTED vim
+
+Vim flags:
+\c	ignore case NOT SUPPORTED vim
+\C	match case NOT SUPPORTED vim
+\m	magic NOT SUPPORTED vim
+\M	nomagic NOT SUPPORTED vim
+\v	verymagic NOT SUPPORTED vim
+\V	verynomagic NOT SUPPORTED vim
+\Z	ignore differences in Unicode combining characters NOT SUPPORTED vim
+
+Magic:
+(?{code})	arbitrary Perl code NOT SUPPORTED perl
+(??{code})	postponed arbitrary Perl code NOT SUPPORTED perl
+(?n)	recursive call to regexp capturing group «n» NOT SUPPORTED
+(?+n)	recursive call to relative group «+n» NOT SUPPORTED
+(?-n)	recursive call to relative group «-n» NOT SUPPORTED
+(?C)	PCRE callout NOT SUPPORTED pcre
+(?R)	recursive call to entire regexp (== (?0)) NOT SUPPORTED
+(?&name)	recursive call to named group NOT SUPPORTED
+(?P=name)	named backreference NOT SUPPORTED
+(?P>name)	recursive call to named group NOT SUPPORTED
+(?(cond)true|false)	conditional branch NOT SUPPORTED
+(?(cond)true)	conditional branch NOT SUPPORTED
+(*ACCEPT)	make regexps more like Prolog NOT SUPPORTED
+(*COMMIT)	NOT SUPPORTED
+(*F)	NOT SUPPORTED
+(*FAIL)	NOT SUPPORTED
+(*MARK)	NOT SUPPORTED
+(*PRUNE)	NOT SUPPORTED
+(*SKIP)	NOT SUPPORTED
+(*THEN)	NOT SUPPORTED
+(*ANY)	set newline convention NOT SUPPORTED
+(*ANYCRLF)	NOT SUPPORTED
+(*CR)	NOT SUPPORTED
+(*CRLF)	NOT SUPPORTED
+(*LF)	NOT SUPPORTED
+(*BSR_ANYCRLF)	set \R convention NOT SUPPORTED pcre
+(*BSR_UNICODE)	NOT SUPPORTED pcre
+