Regular Expressions 101

Pro

(?s)applies the following effective flags to the remainder of the pattern: gms

s modifier: single line. Allows a dot to match line terminators

Negative Lookahead(?!.*?start)

.*?any Unicode character, repeated any number of times

startthe literal text start (case sensitive)

^start of line

Group 1(\w+)

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

\sa Unicode whitespace character

Group 2(\w+)

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

\sa Unicode whitespace character

Group 3(\w+)

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

Positive Lookahead(?=.*?end)

.*?any Unicode character, repeated any number of times

endthe literal text end (case sensitive)

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

(?s)(?!.*?start)^(\w+)\s(\w+)\s(\w+)(?=.*?end)

New

abcd 123 123
start
abcd 123 123
abcd 123 123
abcd 123 123
end
abcd 123 123