Provide props to styled elements in Typescript

themed.ts

import * as React from "react";
import { ThemedStyledFunction } from "styled-components";

const themed = <IComponentProps, U extends HTMLElement = HTMLElement>(
  styled: ThemedStyledFunction<any, any>,
): ThemedStyledFunction<IComponentProps & React.HTMLProps<U>, any> => styled;

export default themed;

// eg.
// import styled, { StyledComponentClass } from "styled-components";
// import themed from "../themed";

// const Foo = themed<IFooProps>(styled.div)`
//   width: 100%;
// `;