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

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