Regular Expressions 101

Explanation
Pro

^start of line

Positive Lookahead(?=.*dog)

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

dogthe literal text dog (case sensitive)

Negative Lookahead(?!.*park)

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

parkthe literal text park (case sensitive)

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

$end of line

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

^(?=.*dog)(?!.*park).*$

New

The dog and the man play in the park.
Man I love that dog!
I'm dog tired.
The dog park is no place for man.
park next to this dog's man.