title: Should I use null for the value of a number - Angular
body: <p>I want an input to initially be set to empty so I set the input's ngModel to null.</p>
  
  <pre><code>&lt;input [(ngModel)]="expenses" (keyup)="onKey($event)"&gt;
  </code></pre>
  
  <p>The model is used like this:</p>
  
  <pre><code>expenses: number = null;
  
  ...
  
  if (this.expenses.toString() === '') {
    this.inputHelperTextVisible = false;
  }
  </code></pre>
  
  <p>Should I use null on a number?</p>