Async load external JS using JS

loadExternalJS.js

export default function loadJS(src: string, args: any) {
  if(!isScriptLoaded(src)) {
    const s: HTMLElement | null = document.createElement('script')
    s.setAttribute('src', src)
    if(args.id) s.setAttribute('id', args.id)
    if(args.cb)
      s.onload = args.cb()
    document.body.appendChild(s)
  }
}

function isScriptLoaded(src: string) {
  const scripts = document.getElementsByTagName('script')
  // is script available
  for (let i = scripts.length; i--;) {
      if (scripts[i].src == src) return true
  }

  return false
}