Negating brush selections

[nathan-uwlm]

I would like to create brush filter that updates bar plots by displaying datapoints within the selection and outside of the selection as separate bars. However, I cannot figure out how to create a bar plot from the negated selection. I am thinking the code would look something like this:

const result = new vg.Plot();
vg.rectY(
    vg.from("flights10m", { filterBy: brush }), // data set and filter selection
    { x: vg.bin(opts.column), y: vg.count(), fill: "steelblue", inset: 0.5 }
)(result);
vg.rectY(
    vg.from("flights10m", { filterBy: negate(brush) }),
    { x: vg.bin(opts.column), y: vg.count(), fill: "pink", inset: 0.5, mixBlendMode: "multiply" }
)(result);
vg.intervalX({ as: brush })(result);

However, there is no negate function I can find. Is there a way to implement this?