Regular Expressions

Regular expressions (regex or regexp) are powerful tools used for pattern matching and searching within text

Source:

• https://www.geeksforgeeks.org/write-regular-expressions/

Regex Cheatsheet §

Character	Meaning	Example
*	Match zero, one, or more of the previous	Ah* matches "Ahhhhh" or "A"
?	Match zero or one of the previous	Ah? matches "A1" or "Ah"
+	Match one or more of the previous	Ah+ matches "Ah" or "Ahhh" but not "A"
\	Used to escape a special character	Hungry\? matches "Hungry?"
.	Wildcard character, matches any character	do.* matches "dog", "door", "dot", etc.
()	Group characters	See example for `	`
[]	Matches a range of characters	[cbf]ar matches "car", "bar", or "far"
		[0-9]+ matches any positive integer
		[a-zA-Z] matches ASCII letters a-z and A-Z
		[^0-9] matches any character not 0-9
`	`	Matches previous OR next character/group	`(Mon)	(Tues)daymatches“Monday”or“Tuesday”`
{}	Matches a specified number of occurrences of the previous	[0-9]{3} matches "315" but not "31"
		[0-9]{2,4} matches "12", "123", and "1234"
		[0-9]{2,} matches "12345..."
^	Matches the beginning of a string or negation in a range	^http matches strings starting with "http", such as a URL
		[^0-9] matches any character not 0-9
$	Matches the end of a string	ing$ matches "exciting" but not "ingenious"