Understanding negative lookahead

Question

I\'m trying to understand how negative lookaheads work on simple examples. For instance, consider the following regex:

Answer 1

@Antario, I was confused about the negative look ahead/behind case in regex for a while and this site has a great explanation.

So with your example what you are saying is that you have a literal "a" and it is NOT followed by a literal "b" and it IS followed by a literal "c".

Here is a different regex debugger than you used which gives a more visual answer which personally I find helpful :)

a(?!b)c

Debuggex Demo