title: Is there a way to find actual SwiftUI API Documentation (and not just the developer documentation)?
body: <p>I’m currently watching the SwiftUI Essentials video from WWDC 2019 and the presenter pulled up the actual API for a VStack, which (incredibly, at least to me) details how this particular struct actually works. </p>
  
  <p>Is there a place for developers to find this sort of detailed, in-depth documentation about particular features provided by Apple?</p>
  
  <p>Matt Stevens has an awesome APIdiff (<a href="http://codeworkshop.net/objc-diff/sdkdiffs/" rel="noreferrer">http://codeworkshop.net/objc-diff/sdkdiffs/</a>) site that he provides, but it all links back to Apple’s standard developer documentation pages. </p>
  
  <p>Sample code provided by the presenter:</p>
  
  <pre><code>public struct VStack&lt;Content : View&gt; : View {
       public init(
            alignment: HorizontalAlignment = .center,
            spacing: Length? = nil,
            @ViewBuilder content: () -&gt; Content
       )
  }
  </code></pre>
  
  <p>Actual provided documentation code:</p>
  
  <pre><code>struct VStack&lt;Content&gt; where Content : View
  </code></pre>
  
  <p>The specifics above regarding the alignment defaults, and the spacing length alone, while super simple, are already being asked as separate SO questions across the site in regards to what and why default behaviors are what they are.</p>
  
  <p>I guess what I’m asking, is for current, more well-established classes in UIKit for example, is there a way to see the actual implementation details of the class themselves such as displayed in this WWDC for a SwiftUI VStack? I’m not sure if this is information that Apple just never gives out and is something that people have learned over time (this acts in a certain way “just because” and we know that from experience) or if this is just the fact that SwiftUI is new and hasn’t had time for Apple solidify SwiftUI and the documentation yet.</p>
  
  <p>Sorry if this has been asked, or if it’s a super obvious question, I’m still pretty new to software development overall. </p>
  
  <p>Thanks!</p>