Regular Expressions 101

Pro

^start of line

Non-Capturing Group(?:Jack\b|(?=\w+(?: +(?!name\b)\w+)* +Jack\b))

1st AlternativeJack\b

Jackthe literal text Jack (case sensitive)

\ba Unicode word boundary

2nd Alternative(?=\w+(?: +(?!name\b)\w+)* +Jack\b)

Positive Lookahead(?=\w+(?: +(?!name\b)\w+)* +Jack\b)

\w+a Unicode word character, repeated at least once

Non-Capturing Group(?: +(?!name\b)\w+)*

*repeats the group contents below any number of times:

+the literal (32₁₀ / 40₈ / 20₁₆) , repeated at least once

Negative Lookahead(?!name\b)

namethe literal text name (case sensitive)

\ba Unicode word boundary

\w+a Unicode word character, repeated at least once

+the literal (32₁₀ / 40₈ / 20₁₆) , repeated at least once

Jackthe literal text Jack (case sensitive)

\ba Unicode word boundary

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

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

No unit tests · Add a test to get started

25 tokens

^(?:Jack\b|(?=\w+(?: +(?!name\b)\w+)* +Jack\b)).*

There are no unit tests, click to add some.