Angular 2 - Does subscribing to FormControl's valueChanges need an unsubscribe? : <p>Below is a simple example of what I am asking about:</p>

<pre><code>class AppComponent {

  someInput: FormControl = new FormControl('');
  private subscription: Subscription;

  constructor(){

    this.subscription = this.someInput.valueChanges
        .subscribe(() =&gt; console.log("testing"));
  }
}
</code></pre>

<p>I have 2 questions:</p>

<p>1) Do I have to eventually unsubscribe from this?
2) Most importantly, whatever the answer is to #1, WHY is that the answer?</p>

<p>Any insight would be appreciated!</p>

<p>Thanks!</p>
