title: Exclude property from type
body: <p>I'd like to exclude a single property from the type. How can I do that?</p>
  <p>For example I have</p>
  <pre class="lang-ts prettyprint-override"><code>interface XYZ {
    x: number;
    y: number;
    z: number;
  }
  </code></pre>
  <p>And I want to exclude property <code>z</code> to get</p>
  <pre class="lang-ts prettyprint-override"><code>type XY = { x: number, y: number };
  </code></pre>