title: Angular 2 Property Does not exist on type
body: <p>I have a Class Like</p>
  
  <pre><code>export class R {
  constructor(
      public id: Number,
      public dte: Date,
      ) { }
  </code></pre>
  
  <p>}</p>
  
  <p>a service That return R[] the code is like :`</p>
  
  <pre><code>return this.http.get(this.serverLocal).map(this.formatDate);
  
    formatDate(res: Response) {
      const data = res.json() as R[];
          data.forEach(D =&gt; {
          D.dte = new Date(D.dte);
      })
      return data;
  }
  </code></pre>
  
  <p>I get the 2 errors: property 'dte' does not exist on type 'R'.
  I changed a lot of code for no avail. It's working if I do some change with ID, but not with dte date. What am I doing wrong?</p>