title: C# WinUI3 - I need help understanding the operator '=>' in the context of the statement: 'Then we exposed the implementation via the App instance'
body: <p>I am trying to navigate via code-behind in my WinUI3 desktop application. I have found this article that explains how to do it. <a href="https://xamlbrewer.wordpress.com/2021/07/06/navigating-in-a-winui-3-desktop-application/" rel="nofollow noreferrer">https://xamlbrewer.wordpress.com/2021/07/06/navigating-in-a-winui-3-desktop-application/</a></p>
  <p>The author of the article has this section:</p>
  <p>*Then we exposed the implementation via the App instance – it knows the Shell because it creates it on start-up:</p>
  <pre><code>private Shell shell;
   
  public INavigation Navigation =&gt; shell;
           
  protected override void OnLaunched(LaunchActivatedEventArgs args)
  {
      shell = new Shell();
      shell.Activate();
  }*
  </code></pre>
  <p>I mainly understand all of the setup that will be required to navigate via code-behind, but I did not understand that one line of code &quot;<strong>public INavigation Navigation =&gt; shell;</strong>&quot;</p>
  <p>My code, where I will insert similar code once I build the interface, etc., looks like this:</p>
  <pre><code>namespace MetricReporting
  {
      public partial class App : Application
      {
          public App()
          {
              this.InitializeComponent();
          }
  
          protected override void OnLaunched(Microsoft.UI.Xaml.LaunchActivatedEventArgs args)
          {
              m_window = new MainWindow();
              m_window.Activate();
          }
  
          private Window m_window;
      }
  }
  </code></pre>
  <p>That code line in question should be &quot;<strong>public INavigation Navigation =&gt; m_window;</strong>&quot; (This is my understanding) to work with my application.</p>
  <p>I appreciate anyone who can explain what this line is doing.
  Sincerely.</p>