title: IE 11 react 'promise' is undefined
body: <p>I am trying to load a page which is built using react. when the page loads there is a table which is rendered using react. this table doesn't load currently on IE and throws error promise is not defined. the exact same code with promise works on other browsers. below is the code.</p>
  
  <pre><code>fetchData(url) {
      // Return a new promise.
      return new Promise(function (resolve, reject) {
          $.ajax(
              {
                  url: url,
                  cache: false,
                  context: this,
                  dataType: 'json',   // we're expecting JSON as a response
                  data: {},
                  method: "GET",
                  contentType: "application/json; charset=utf-8",
                  success: function (data, status, xhr) {
                      resolve(JSON.parse(data));
                  },
                  error: function (xhr, status, httpErrorText) {
                      reject(httpErrorText);
                  }
              });
      });
  }
  </code></pre>
  
  <p>any ideas why this is happening and how to fix this.</p>