I recall reading that using operator (Spivak) style derivative notation, we can unify notation for derivative, partial derivative, Jacobian, and I believe more.
If $f: \mathbb R ^n \to \mathbb R ^m$ (and $n$ and $m$ can of course be $1$), we define $Df$ to be $Df: R ^n \to \mathbb R ^m$. This includes the single-variable derivative and the Jacobian as well.
There was more in the reference, but I can't remember it exactly. They used index and subscripts to pluck out the partial derivatives and other things, without introducing any new notation - it was the same usage of index and subscripts across the board, perhaps the same as used for matrices or vectors. The main idea was subscripts and indices were the same for any $n \to m$ function; derivatives were simply such a function, nothing more, nothing less.
I thought that this was from Spivak, and while I can find his notation starting in this direction, I can't find the whole idea.
So: Is there a reference showing unified notation for derivative operators with indexes and subscripts to unify $n \to m$ functions, derivatives, partial derivatives, and Jacobians, treating them all with the same notation?
A small list of references: