negative lookahead (@!) together with very magic \v

Question

I am struggling combining a negative lookahead assertion @! with the very magic specifier \v

I have a buffer with this content

<div class='vvv'>abc</div>
<div class='ttt'>abc</div>

and I want to search for all classes except vvv. I can do this like so

/class=.\(vvv\)\@!

This finds the second line (class='ttt'), as expected. Yet, when I try to search with the very magic modifier:

/\vclass=.(vvv)@!

the search finds both classes. I had wrongly assumed these searches to be equivalent. Why are they different?

Answer 1

The code you wrote is perfect but in \v mode = needs protection.

\vclass\='(ttt)@!

In normal mode \= means optional (the same as \?). In \v mode, = means optional: class= ends up meaning class|clas (I would prefer = were just a normal char).

So, to mark the classes different form ttt we can:

:%s/\vclass\='(ttt)@!.{-}'/MARKED&/

When we have more complex "different-from" patterns it may be easier the long way:

:%s/\vclass\='(tt1|...)'/classAUX=\1/          rename exceptions
:%s/\vclass\='.{-}'/MARKED&/                   treat normal cases
:%s/\vclassAUX/class/                          unrename

\thanks{Peter Lewerin}