Idea/Question: Logical combinations matching on single line

Is there a way to scope logical combination matching to the same line?

I want to match a pattern but only if another pattern doesn't match on the same line.
So I want a logical combination like (!A & B) where the expression is true if A and B are on separate lines or A doesn't appear at all, and false if A and B occur on the same line.

Thus far from my experimentation it seems logical combination just operates on the entire stream of content which means instead I have to write logic to capture the start lines of results for two patterns and compare them all to see how they line up.

Thanks!