It would seem that someone's done it already: https://github.com/DefinitelyTyped/DefinitelyTyped/blob/master/types/transducers-js/index.d.ts#L70 https://github.

It would seem that someone's done it already: https://github.com/DefinitelyTyped/DefinitelyTyped/blob/master/types/transducers-js/index.d.ts#L70 https://github.com/DefinitelyTyped/DefinitelyTyped/blob/mast...