title: Reactive Extensions Subscribe calling await
body: <p>I want to perform an async call based for each <em>event</em> raised by a Reactive Extensions Observable. I'm also trying to keep everything synchronized as I want the async call to finish before the next event is handled.</p>
  
  <p>How would one go about doing something similar to the following? I say similar as the code below does not compile.</p>
  
  <pre><code>settingsChangedInMemory
      .Subscribe(async _ =&gt; {
          var settings = Extract();
          await SaveSettings(settings);
      });
  </code></pre>
  
  <p>I'm not sure if it changes anything, but I would need to Subscribe to multiple Observables. For example another subscription like this.</p>
  
  <pre><code>settingsChangedOnDisk
      .Subscribe(async _ =&gt; {
          var settings = await ReadSettings(settings);
          Apply(settings);
      });
  </code></pre>
  
  <p>How would you use Reactive Extensions to do this?</p>