Regular Expressions 101

Pro

^start of line

Group 1((xxx|yyy)(,(?!$)|$))+

+repeats the group contents below at least once:

Group 2(xxx|yyy)

1st Alternativexxx

xxxthe literal text xxx (case sensitive)

2nd Alternativeyyy

yyythe literal text yyy (case sensitive)

Group 3(,(?!$)|$)

1st Alternative,(?!$)

,the literal , (44₁₀ / 54₈ / 2C₁₆)

Negative Lookahead(?!$)

$end of line

2nd Alternative$

$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

^((xxx|yyy)(,(?!$)|$))+$

New

xxx
yyy
xxx,xxx
yyy,xxx
xxx,yyy,yyy,yyy

 
xx
yyyy
xxx,
xxxyyy
xxx,,yyy
,xxx,yyy