Discussion on: Creating a typed "compose" function in TypeScript

export function compose<R, F extends (a: R, ...b: any) => R>(
  fn1: F,
  ...fns: Array<(a: R) => R>
) {
  return fns.reduce(
    (prevFn, nextFn) => value => prevFn(nextFn(value)),
    fn1
  ) as F;
}

const a = (v: string, q: number, s: boolean) => v + q;
const b = (v: string) => v;

const c = compose(a, b, b, b, b, b, b);