title: angular4 ngValue does not show selected value
body: <p>angular4</p>
  
  <p>having trouble with select [ngValue] showing selected value from model</p>
  
  <pre><code>&lt;select [(ngModel)]="model.o"&gt;
  &lt;option *ngFor="let o of objs" [ngValue]="o"&gt;&lt;/option&gt;
  &lt;/select&gt;
  </code></pre>
  
  <p>works fine but does not show selected object from model. but if i change <code>[ngValue]</code> to <code>[value]</code> it shows selected but then pass value as a string.</p>
  
  <p>can some one help pls.</p>