title: Using react native async storage getItem
body: <pre class="lang-rut prettyprint-override"><code>  React.useEffect(_ =&gt; {
      ReactNativeAsyncStorage.getItem("jwt")
      |&gt; Js.Promise.then_(jwt =&gt; {Js.log(jwt)});
      None;
    });
  </code></pre>
  
  <p>Error:</p>
  
  <pre><code>This expression has type unit but an expression was expected of type
           Js.Promise.t('a) = Js.Promise.t('a)
  </code></pre>
  
  <p>I am using <a href="https://github.com/reason-react-native/async-storage" rel="nofollow noreferrer">https://github.com/reason-react-native/async-storage</a> with <a href="https://github.com/react-native-community/async-storage" rel="nofollow noreferrer">https://github.com/react-native-community/async-storage</a></p>