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        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - Arrow Function before super() causes TDZ, should it?"
   href="https://bugs.webkit.org/show_bug.cgi?id=149338">149338</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>Arrow Function before super() causes TDZ, should it?
          </td>
        </tr>

        <tr>
          <th>Classification</th>
          <td>Unclassified
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>WebKit
          </td>
        </tr>

        <tr>
          <th>Version</th>
          <td>WebKit Nightly Build
          </td>
        </tr>

        <tr>
          <th>Hardware</th>
          <td>Unspecified
          </td>
        </tr>

        <tr>
          <th>OS</th>
          <td>Unspecified
          </td>
        </tr>

        <tr>
          <th>Status</th>
          <td>NEW
          </td>
        </tr>

        <tr>
          <th>Severity</th>
          <td>Normal
          </td>
        </tr>

        <tr>
          <th>Priority</th>
          <td>P2
          </td>
        </tr>

        <tr>
          <th>Component</th>
          <td>JavaScriptCore
          </td>
        </tr>

        <tr>
          <th>Assignee</th>
          <td>webkit-unassigned&#64;lists.webkit.org
          </td>
        </tr>

        <tr>
          <th>Reporter</th>
          <td>joepeck&#64;webkit.org
          </td>
        </tr>

        <tr>
          <th>CC</th>
          <td>bburg&#64;apple.com, gskachkov&#64;gmail.com, sbarati&#64;apple.com, utatane.tea&#64;gmail.com
          </td>
        </tr></table>
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        <div>
        <pre>* SUMMARY
Arrow Function before super() causes TDZ, should it?

You get a non-obvious TDZ runtime ReferenceError when you create an arrow function before calling super() in a subclass.

* TEST
&lt;script&gt;
class Parent { }
class Subclass extends Parent {
    constructor() {
        let x = () =&gt; {}; // TDZ because of capturing &quot;this&quot;
        super();
    }
}
console.log(new Subclass);
&lt;/script&gt;

* PRODUCES
[Error] ReferenceError: Cannot access uninitialized variable.
    Subclass
    (anonymous function)</pre>
        </div>
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