regex

🔍 Regex Shortcuts

Shortcut	Action
*	Match preceding character 0 or more times
+	Match preceding character 1 or more times
.	Match any single character
x|y	Match either ‘x’ or ‘y’
\	Escape a special character
b	The character b
abc	The string abc

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🧩 Regex Character Class Shortcuts

Shortcut	Action
\d	Match a digit character
\D	Match a non-digit character
\s	Match a single white space character (space, tab, form feed, or line feed)
\S	Match a single character other than white space
\w	Match any alphanumeric character (including underscore)
\W	Match any non-word character

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🔠 Regex Character Set Shortcuts

Shortcut	Action
[abc]	Match any one of the characters in the set ‘abc’
[^abc]	Match anything not in character set ‘abc’
[\b]	Match a backspace

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🔍 Advanced Regex Shortcuts

Shortcut	Action
^	Match beginning of input
$	Match end of input
\b	Match a word boundary
\B	Match a non-word boundary
?=	Lookahead
?!	Negative lookahead

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🔄 Conditional Regex Shortcuts

Shortcut	Action
?<=	Lookbehind
?<!	Negative lookbehind
?>	Once-only subexpression
?()	If-then condition
?()|	If-then-else condition
?#	Comment

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🔢 Regex Quantifier Shortcuts

Shortcut	Action
{n}	Match exactly n occurrences of preceding character
{n,m}	Match at least n and at most m occurrences of the preceding character
?	Match 0 or 1 occurrence of preceding character

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🧩 Regex Escape Sequences

Shortcut	Action
\cX	Match control character X in a string
\n	Match a line feed
\r	Match a carriage return
\t	Match a tab
\0	Match a NULL

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🧩 Advanced Regex Escape Sequences

Shortcut	Action
\f	Match a form feed
\v	Match a vertical tab
\xhh	Match character with code hh (2 hex digits)
\uhhhh	Match character with code hhhh (4 hex digits)

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🔍 Search Option Shortcuts

Shortcut	Action
g	Global search
i	Case-insensitive search
m	Multi-line search
y	“Sticky” search match starting at current position in target string

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🧑‍🤝‍🧑 Grouping & Back-Reference Shortcuts

Shortcut	Action
(x)	Match ‘x’ and remember the match
(?:x)	Match ‘x’ but do not remember the match
\n	A back reference to the last substring matching the n parenthetical in the regex