useScript.ts

import { useEffect, useState } from 'react';

let loadedScripts: Map<string, Promise<null>> = new Map();

export default function useScript(src: string) {
  let [isLoaded, setLoaded] = useState(false);
  useEffect(() => {
    let promise = loadedScripts.get(src) || loadScript(src);
    promise.then(() => {
      setLoaded(true);
    });
  }, []);
  return isLoaded;
}

function loadScript(src: string) {
  let promise: Promise<null> = new Promise((resolve, reject) => {
    let script = document.createElement('script');
    script.src = src;
    script.async = true;
    script.addEventListener('load', () => {
      resolve(null);
    });
    script.addEventListener('error', (event: Event) => {
      script.parentNode && script.parentNode.removeChild(script);
      reject(event);
    });
    document.head && document.head.appendChild(script);
  });
  loadedScripts.set(src, promise);
  return promise;
}