RegEx

Notes for RegEx respectively Regular Expressions.

Guide (german): https://t3n.de/news/regex-guide-t3n-552858/

Other guide: https://www.rexegg.com/regex-quickstart.html

Interactive tutorial: https://regexone.com/

General Rules

Character Types

Type	Example
Literal	a b c 1 2 3
Meta characters	. [[ ] { } ? * + | ( ) ^ $

Meaning of meta characters

Meaning	Example
Character class digit	d
Character class character	w
Character class whitespace	s
Inversion of Character Classes	D, W, S, [^abc]
Character class range	[a-c]
Single Character	.
Grouping with alternatives	Tues)day
Word and text boundaries	b ^ $

Multiplier

Multiplier	Example
Multiplier	{42}, {4,20}
One or more characters	+
Zero or one character	?
Zero or more characters	*