Regular Expressions 101

Non-Capturing Group(?:(?!.*(Swans).*))

Negative Lookahead(?!.*(Swans).*)

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

Group 1(Swans)

Swansthe literal text Swans (case sensitive)

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

Negative Lookahead(?!.*(Swans).*)

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

Group 2(Swans)

Swansthe literal text Swans (case sensitive)

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

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

Detailed match information will be displayed here automatically.

Search reference

Regular Expression

(?:(?!.*(Swans).*)).*(?!.*(Swans).*)

New

Seven Swans a Swimming
Six Geese a Laying
Five Golden Rings
Four Calling Birds
Three French Hens
Two Turtle Doves
and a Partridge in a Pear Tree