typescript extend imported namespace
// We can import a namespace in a non-declaration .ts, and export it again as a extended type:
// custom-fc.ts : enhances declaration of FC namespace
import * as origFC from "fullcalendar";
declare namespace Complimentary {
class TimeGrid {
prepareHits(): void;
}
let views: any;
}
// apply additional types to origFc and export again
export const FC: (typeof Complimentary & typeof origFC) = origFC as any;