RegExp	Description
x y	Match the x then y
x \| y	Match either the x or y
x *	Match the x zero or more times
x +	Match the x one or more times
x ?	Match the x zero or one times
(:? x )	Non-capturing group
( x )	Capturing group
\p{ N }	Char of the general category N
\P{ N }	Char not of the general category N
[ x ]	Character class x
[^ x ]	Character not in the class x
[ x - y ]	Character in range x..y
[\p{ N }]	Char of the general category N
[\P{ N }]	Char not of the general category N
^	Start of line assertion
$	End of line assertion
\b	Word boundary assertion
\B	Not a word boundary assertion
x	Character literal x, not in `^$.*+?]{}`
\ x	Character literal x in `^$.*+?]{}`
\n \r \t	New line, tabulation and other controls
[\n\r]	The same in a character class

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