Regexp Syntax Summary

http://www.greenend.org.uk/rjk/tech/regexp.html

 

String	GNU grep	BRE (grep)	ERE (egrep)	GNU Emacs	Perl	Python	Tcl
.	Any character	Any character except \0		Any character except \n			Any character
[...]	Bracket Expression			Character Set	Character Class		Bracket Expression
\(re\)	Subexpression			Grouping
re\{...\}	Match re multiple times			Match re multiple times
(re)			Subexpression		Grouping
re{...}			Match re multiple times		Match re multiple times
re{...}?					Nongreedy {}
\digit	Back-reference
^	Start of line
$	End of line
re?			re 0 or 1 times
re*	re 0 or more times
re+			re one or more times
l|r			l or r		l or r
*?				Non-greedy *
+?				Non-greedy +
??				Non-greedy ?
\A					Start of string
\b	Either end of word			Either end of word
\B	Not either end of word			Not either end of word			Synonym for \
\cC				Any in category C
\CC				Any not in category C
\C					Any octet
\d					Digit
\D					Non-digit
\G					At pos()
\m							Start of word
\M							End of word
\pproperty  \p{property}					Unicode property
\Pproperty  \P{property}					Not unicode property
\sC				Any with syntax C
\SC				Any with syntax not C
\s					Whitespace
\S					Non-whitespace
\w	Same as [[:alnum]]			Same as \sw	Alphanumeric and _
\W	Same as [^[:alnum]]			Same as \Sw	Not alphanumeric or _
\X					Combining sequence
\y							Either end of word
\y							Not either end of word
\Z					End of string/last line	End of string
\z					End of string
\`				Start of buffer/string
\'				End of buffer/string
\<	Start of word			Start of word
\>	End of word			End of word
re\?	re 0 or 1
re\+	re 1 or more
l\|r	l or r			l or r
(?#text)					Comment, ignored
(?modifiers)					Embedded modifiers
(?modifiers:re)					Shy grouping + modifiers
(?:re)					Shy grouping
\(?:...\)				Shy grouping
(?=re)					Lookahead
(?!re)					Negative lookahead
(?<=p)					Lookbehind
(?<!o)					Negative lookbehind
(?{code})  (??{code})					Embedded Perl
(?>re)					Independent expression
(?(cond)re)  (?(cond)re|re)					Condition expression
(?P<name>re)						Symbolic grouping
(?P=name)						Symbolic backref
String	GNU grep	BRE (grep)	ERE (egrep)	GNU Emacs	Perl	Python	Tcl