Regular Expressions 101

Pro

^start of line

Positive Lookahead(?=.*\bgood foo\b)

.*any character (except for line terminators), repeated any number of times

\ban ASCII word boundary

good foothe literal text good foo (case sensitive)

\ban ASCII word boundary

Negative Lookahead(?!.*\bgood koo\b)

.*any character (except for line terminators), repeated any number of times

\ban ASCII word boundary

good koothe literal text good koo (case sensitive)

\ban ASCII word boundary

.*any character (except for line terminators), repeated any number of times

$end of line

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string

Detailed match information will be displayed here automatically.

25 tokens

^(?=.*\bgood foo\b)(?!.*\bgood koo\b).*$

New

some text good foo and some text and good koo 
good foo and some text (no indication of koo)

some text good foo and some text and good koo 
good foo and some text (no indication of koo)