Promise is undefined in IE11 using babel-polyfill

Question

As the title says, even I\'d like to use babel-polyfill to allow me to use promises in my code, but I get that undefined error in IE11.

I\'ve been trying to make this wo

Answer 1

You need to import Babel polyfilly before any other non-polyfill code in your JS entry point:

import 'babel-polyfill';

or if you have already switched to Babel 7:

import '@babel/polyfill';

Also note that you should switch your presets to preset-env. I'd recommend you upgrade to Babel 7 and use @babel/preset-env.

Assuming you have done the switch to Babel 7, this is what your .babelrc should look like:

{
  "presets": [
    [ "@babel/preset-env", {
      "targets": {
        "browsers": [ "last 1 version", "ie >= 11" ]
      }
    }]
  ]
}

Answer 2

From Babel 7.4.0 you need to install and import these libraries:

import "core-js/stable";
import "regenerator-runtime/runtime";

like they said here: https://babeljs.io/docs/en/babel-polyfill