title: Getting error "Property used before its initialization". I am trying to get user id from firebase so I can add it to a message object
body: <p>Here is my code</p>
  <pre><code>  user: firebase.default.User;
    constructor(public afAuth: AngularFireAuth, private db: AngularFirestore) {
      afAuth.user.subscribe(data =&gt; {
        this.user = data;
      })
    }
  
    post = {
      message: 'hello world',
      uid: this.user.uid, //getting the error right here **Property 'user' used before its initialization
    }
  </code></pre>
  <p>This isn't making sense to me since I am initializing the user variable in the constructor. Please go easy on me I am new to angular and also somewhat new to firebase.</p>