<p dir="auto">This is a duplicate of <a class="issue-link js-issue-link" data-error-text="Failed to load title" data-id="120770764" data-permission-text="Title is private" data-url="https://github.com/angular/angular/issues/5662" data-hovercard-type="issue" data-hovercard-url="/angular/angular/issues/5662/hovercard" href="https://github.com/angular/angular/issues/5662">#5662</a> but I'm still creating this issue as it happens with Angular 2.0 RC1.</p>
<p dir="auto">Here's the error</p>
<div class="snippet-clipboard-content notranslate position-relative overflow-auto" data-snippet-clipboard-copy-content="Chrome 51.0.2704 (Windows 7 0.0.0): Executed 0 of 3 SUCCESS (0 secs / 0 secs)
Chrome 51.0.2704 (Windows 7 0.0.0): Executed 2 of 3 SUCCESS (0 secs / 0.02 secs)
ERROR: 'Potentially unhandled rejection [2] Failed to load /app/app.component.html (WARNING: non-Error used)'"><pre class="notranslate"><code class="notranslate">Chrome 51.0.2704 (Windows 7 0.0.0): Executed 0 of 3 SUCCESS (0 secs / 0 secs)
Chrome 51.0.2704 (Windows 7 0.0.0): Executed 2 of 3 SUCCESS (0 secs / 0.02 secs)
ERROR: 'Potentially unhandled rejection [2] Failed to load /app/app.component.html (WARNING: non-Error used)'
</code></pre></div>
<p dir="auto">Suppose you have this class hierarchy<br>
A<br>
|<br>
B<br>
and A implements OnInit but B does not explicitly declare that it implements OnInit, only that it extends A.  Then angular will (incorrectly) not call ngOnInit when it creates an instance of B.</p>