Regular Expressions 101

Pro

Non-Capturing Group(?:\G(?!^)|string1)

1st Alternative\G(?!^)

\Gstart of current search

Negative Lookahead(?!^)

^start of line

2nd Alternativestring1

string1the literal text string1 (case sensitive)

Non-Capturing Group(?:(?!string1|string2).)*?

*?repeats the group contents below any number of times:

Negative Lookahead(?!string1|string2)

1st Alternativestring1

string1the literal text string1 (case sensitive)

2nd Alternativestring2

string2the literal text string2 (case sensitive)

.any character (except for line terminators)

\Kresets the starting point of the reported match. Any previously consumed characters are no longer included in the final match

\hany horizontal whitespace character

Positive Lookahead(?=.*string2)

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

string2the literal text string2 (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

(?:\G(?!^)|string1)(?:(?!string1|string2).)*?\K\h(?=.*string2)

New

string1 this is a first example string2
string1 this is a second example string2

_

string1 this is a first example string2
string1 this is a second example string2