`import` is the keyword in IE even it's a property

  function SystemJS () {
    this[REGISTRY] = {};
  }

  var systemJSPrototype = SystemJS.prototype;

  systemJSPrototype.import = function (id, parentUrl) {
    var loader = this;
    return Promise.resolve(loader.prepareImport())
    .then(function() {
      return loader.resolve(id, parentUrl);
    })
    .then(function (id) {
      var load = getOrCreateLoad(loader, id);
      return load.C || topLevelLoad(loader, load);
    });
  };

systemJSPrototype.import is work in the modern browser, but it doesn’t work in IE

even

const obj = {
  import: () => {} // throw in IE
}

function Module () {}

Module.import = function () {} // throw in IE

System.import('/xxx.js'); // throw in IE

This makes system.js not work in IE(including IE11) at all.

[guybedford]

@axetroy as mentioned above there are other concerns here regarding IE<11 support. The only version of IE that is supported is IE11 (within which import is supported without quotes).

[axetroy]

@joeldenning This is not a polyfill problem.

Is this my description is not clear enough?

I mean import is a keyword in IE(7,8,9,10,11).

Even if it’s a property like object.import = function () {}

This will cause the exception to be unusable in IE.

This is not a problem that polyfills can solve.