Cheat sheet on some of the available parameters for regular expressions

This is a quick cheat sheet on some of the available parameters for regular expressions.

• How to handle alphanumeric characters and digits in a regular expression pattern?

Character	Description	Example pattern	Example match
\d	Digit	name_\d\d	name_11
\D	Non digit	\D\D\D	XYZ
\w	Alphanumeric characters	\w-\w\w\w	B-a_2
\W	Non alphanumeric characters	\W\W\W\W\W	*-+=)
\s	Contains a whitespace	x\sy\sz	x y z
\S	Doesn’t contain a whitespace	\S\S\S\S	ATEST

• How to handle occurrence in a regular expression pattern?

Character	Description	Example pattern	Example match
{2}	Occurs exactly 2 times	\D{2}	xy
{2,3}	Occurs 2 to 3 times	\d{2,4}	789
{4}	Occurs 4 or more times	\w{3,}	yyyxxxaaa
*	Occurs zero or more times	X\*Y\*Z*	YYYZZ
?	Occurs once or none	text?	text
+	Occurs one or more times	Chapter \w-\w+	Chapter A-z2_2

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I hope this was useful to you and let’s see what’s next?

Greetings,

Thomas

#regularexpression, #regex, #occurrence, #alphanumeric, #digit, #char, #characters, #cheatsheet