Regular Expression Quick Guide

Metacharacter	Description
^	Matches the beginning of a line
$	Matches the end of the line
.	Matches any character
\s	Matches whitespace
\S	Matches any non-whitespace character
*	Repeats a character zero or more times
*?	Repeats a character zero or more times(non-greedy)
+	Repeats a character one or more times
+?	Repeats a character one or more times(non-greedy)
[aeiou]	Matches a single character in the listed set
[^XYZ]	Matches a single character not in the listed set
[a-z0-9]	The set of characters can include a range
(pattern)	Defines a marked subexpression to extract
(?:pattern)	Defines a marked subexpression not to extract
x|y	Matches any one of several subexpressions
?	Matches the preceding subexpression zero or one time
{n}	Matches the preceding subexpression n times
{n,}	Matches the preceding subexpression at least n times
{n,m}	Matches the preceding subexpression at least n and not more than m times

Assertion	Lookbehind	Lookahead
Positive	(?<=pattern)	(?=pattern)
Negative	(?<!pattern)	(?!pattern)

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