easy_rule with Jacobian operator

I am wondering if it would be possible to extend `@easy_rule` so that forming a Jacobian would not be needed.

For concreteness, consider a `f(x::AbstractVector)::AbstractVector` function, with Jacobian `J`. My understanding is that for forward and reverse mode, `Jv` and `vJ` are sufficient, and one would not need to actually instantiate `J`, just a matrix-like object that can form said products.

(Apologies if this is already supported and I missed it)