Firebase and ObjC: use of undeclared identifier 'user'
<p>My project uses both swift 3 and objective C so my appDelegate is in Swift.</p>

<p>I'm importing Firebase.h into the objective C code and I can access and add data to Firebase.   But when I try to use the child:user.uid to apply it to the logged in user I get the undeclared error on the user object:</p>

<pre><code>[[[[[FIRDatabase database] reference] child:@"user"] child:user.uid] setValue:@{@"fname":@"bob"}];
</code></pre>

<p><a href="https://i.stack.imgur.com/d6MY6.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/d6MY6.png" alt="Image of error message"></a></p>