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RegexBuddy—Better than a regular expression reference!

Regular Expression Reference: Basic Features

FeatureSyntaxDescriptionExample JGsoft .NET Java Perl PCRE PCRE2 PHP Delphi R JavaScript VBScript XRegExp Python Ruby std::regex Boost Tcl ARE POSIX BRE POSIX ERE GNU BRE GNU ERE Oracle XML XPath
Dot . (dot) Matches any single character except line break characters. Most regex flavors have an option to make the dot match line break characters too. . matches x or (almost) any other character YESYESYESYESYESYESYESYESYESYESYESYESYESYESYESYESYESYESYESYESYESYESYESYES
Not a line break \N Matches any single character except line break characters, like the dot, but is not affected by any options that make the dot match all characters including line breaks. \N matches x or any other character that is not a line break V2nono5.128.10YES5.3.4XE7YESnonononononononononononononono
Alternation | (pipe) Causes the regex engine to match either the part on the left side, or the part on the right side. Can be strung together into a series of alternatives. abc|def|xyz matches abc, def or xyz YESYESYESYESYESYESYESYESYESYESYESYESYESYESECMA
extended
egrep
awk		ECMA
extended
egrep
awk		YESnoYESnoYESYESYESYES
Alternation \| (backslash pipe) Causes the regex engine to match either the part on the left side, or the part on the right side. Can be strung together into a series of alternatives. abc\|def\|xyz matches abc, def or xyz nononononononononononononononononononoYESnononono
Alternation Literal line feed not inside a group or character class Causes the regex engine to match either the part on the left side, or the part on the right side. Can be strung together into a series of alternatives. abc
def
xyz matches abc, def or xyz		 nonononononononononononononogrep
egrep		grep
egrep		nononononononono
Alternation Literal line feed inside a group but not inside a character class Causes the group to match either the part on the left side, or the part on the right side. Can be strung together into a series of alternatives. a(bc
de
fg)h matches abch, adeh or afgh		 nononononononononononononononogrep
egrep		nononononononono
Alternation is eager | or \| Alternation returns the first alternative that matches. a|ab matches a in ab YESYESYESYESYESYESYESYESYESYESYESYESYESYESECMAECMAnon/anononoYESYESYES
Alternation is greedy | or \| Alternation returns the longest alternative that matches. a|ab matches ab in ab nonononononononononononononoextended
grep
egrep
awk		extended
grep
egrep
awk		YESn/aYESYESYESnonono
FeatureSyntaxDescriptionExample JGsoft .NET Java Perl PCRE PCRE2 PHP Delphi R JavaScript VBScript XRegExp Python Ruby std::regex Boost Tcl ARE POSIX BRE POSIX ERE GNU BRE GNU ERE Oracle XML XPath

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