title: Using @babel/plugin-proposal-nullish-coalescing-operator with "babel-preset-expo"
body: <p>The project was created with create-react-native-app.</p>
  
  <p>When I use code like <code>const a = 2 ?? 3</code>, there will be an error complaining <strong>"Cannot read property 'loose' of undefined"</strong>.</p>
  
  <p>I tried adding the <a href="https://github.com/babel/babel/tree/master/packages/babel-plugin-proposal-nullish-coalescing-operator" rel="nofollow noreferrer">@babel/plugin-proposal-nullish-coalescing-operator</a> plugin, but there's a build error.</p>
  
  <h2>.babelrc</h2>
  
  <pre><code>{
    "presets": ["babel-preset-expo"],
    "env": {
      "development": {
        "plugins": ["transform-react-jsx-source"]
      }
    },
    "plugins": ["@babel/plugin-proposal-nullish-coalescing-operator"]
  }
  </code></pre>
  
  <p><a href="https://i.stack.imgur.com/qDmBt.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/qDmBt.png" alt="enter image description here"></a></p>