Just a little convenient when you want to dynamically loading some scripts(and css).

(For example, within the tag of riot.js)

var rcLoader = function(files, then) {
  var p = [];
  function _load(type, url) {
    return new Promise(function(resolve) {
      var el;
      var parent = 'body';
      if (type == 'js') {
        el = document.createElement('script');
        el.async = true;
        el.src = url;
      }
      else if (type == 'css') {
        el = document.createElement('link');
        el.type = 'text/css';
        el.rel = 'stylesheet';
        el.href = url;
        parent = 'head';
      }
      el.onload = function() { resolve(url); };
      document[parent].appendChild(el);
    });
  }
  function _loader(file) {
    if (file.match(/^js: (.+)/)) {
      p.push(_load('js', RegExp.$1));
    }
    else if (file.match(/^css: (.+)/)) {
      p.push(_load('css', RegExp.$1));
    }
  }
  if (typeof files == 'string') { _loader(files); }
  else {
    files.forEach(function(v) { _loader(v); });
  }
  Promise.all(p).then(then);
};

How to use

rcLoader([
  'js: //ajax.googleapis.com/ajax/libs/jquery/3.1.1/jquery.min.js',
  'css: //cdnjs.cloudflare.com/ajax/libs/materialize/0.98.2/css/materialize.min.css',
  'js: //cdnjs.cloudflare.com/ajax/libs/materialize/0.98.2/js/materialize.min.js',
], function() {
  hljs.initHighlightingOnLoad();
  $(function() {
    $('#common').html('common');
  });
});

The first argument may be a character string.

When you use IE or other old browser, use it.