Regular Expressions 101

Pro

1st Alternative(?:^(?:(?!#summertime).)*$|^.*?#summertime)(*SKIP)(*F)

Non-Capturing Group(?:^(?:(?!#summertime).)*$|^.*?#summertime)

1st Alternative^(?:(?!#summertime).)*$

^start of line

Non-Capturing Group(?:(?!#summertime).)*

*repeats the group contents below any number of times:

Negative Lookahead(?!#summertime)

#summertimethe literal text #summertime (case sensitive)

.any character (except for line terminators)

$end of line

2nd Alternative^.*?#summertime

^start of line

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

#summertimethe literal text #summertime (case sensitive)

(*SKIP)acts like (*PRUNE), but the next unanchored match attempt starts where (*SKIP) was reached instead of at the next subject character

(*F)forces the current match attempt to fail at this position

2nd Alternative\w+

\w+any word character, repeated at least once

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

(?:^(?:(?!#summertime).)*$|^.*?#summertime)(*SKIP)(*F)|\w+

New

foo bar
#summertime swimming, running, tanning
swimming, running, tanning

foo bar
#summertime swimming, running, tanning
swimming, running, tanning