Is it (`?:`) typescript ternary operator : <p>I'm new to angular 2 and typescript.
I am seeing </p>

<pre><code> export interface EjectTaskOptions extends BuildOptions {
  force?: boolean;
  app?: string;
}
</code></pre>

<p>in some typescript examples. What is it (<code>?:</code>) mean ?
Is it a ternary operator (with only false condition)or some other ?</p>

<p>Thanks in advance.</p>
