anchor.diff:  }
   const resources = ["/resource/A", "/resource/B"];
   // リソースを取得して出力する
  -fetchResources(resources).then((results) => {
  +fetchResources(resources).then(function(results){
       // resultsは空になってしまう
       console.log(results); // => []
   });
  
positive.code: [source,javascript]
  ----
  function dummyFetch(path) {
      return new Promise((resolve, reject) => {
          setTimeout(() => {
              if (path.startsWith("/resource")) {
                  resolve({ body: `Response body of ${path}` });
              } else {
  
negative.code:         dummyFetch("/resource/A"),
          dummyFetch("/resource/B")
      ]);
      return responses.map(function(response){
          return response.body;
      });
  }
  // リソースを取得して出力する
  fetchResources().then(function(results){
      console.log(results); // => ["Response body of /resource/A", "Response body of /resource/B"]
  });
  ----
  