Can't use constructors with JS interop

[qgcarver]

If I try to pass in a function that takes in a constructor as a parameter, the closure I send in doesn't treat it that way.

lua.global.set("DOM",{
    new: (T=>{
        let Constructor = T;
        return (...a) => {
            let constructed = new Constructor(...a);
            return constructed;
        };
    }),
    window: window
    log: console.log
    exampleElement: document.getElementById("mycanvas")
}),

lua.doString(`
function f()
  local ImageConstructor = DOM.new(DOM.window.Image)
  DOM.log(ImageConstructor())
end
DOM.exampleElement.onclick = f
`)

I get an error saying n is not a constructor
I tried currying and saving a local as seen above to try to work around this, but it seems like there's some kind of wrapping going on that's preventing that from working.
It seems like a way to support constructors in the interop system itself would be good, (if it doesn't already exist and I just missed it.)