trpc - Calling a route inside itself

const caller = route.createCaller({})

import { z } from "zod";

import { router, publicProcedure } from "../trpc";

export const appRouter = router({
  example: exampleRouter,
});

export const exampleRouter = router({
  hello: publicProcedure.query(() => "Hello"),
  world: publicProcedure.query(() => "World"),
  greet: publicProcedure.query(function () {
    const caller = this.createCaller({});
    // const caller = appRouter.createCaller({}) ????
    return caller.hello() + caller.world();
  }),
});