title: Detect changes @Input binding in angular
body: <p>I need to detect value changes in <code>@Input</code> binding angular and execute a function when the value is changed</p>
  
  <pre class="lang-js prettyprint-override"><code>@Component({
    selector: 'my-comp',
    ...
  })
  ...
  @Input() myValue
  
  //detect myValue changes
  
  </code></pre>
  
  <pre class="lang-html prettyprint-override"><code>&lt;my-comp [myValue]= "val"&gt;&lt;/my-comp&gt;
  </code></pre>
  
  <p>I need to execute some code component class when <code>val</code> changes. </p>