title: Cocoapods does not recognise static constants in a struct in Swift
body: <p>I am uploading my lib to Cocoapods. After all is written, I ran <code>pod spec lint DWActionsMenu.podspec</code> and ran into a weird error.</p>
  
  <p>Here is the key line of my podspec:</p>
  
  <pre><code>s.source_files  = 'DWActionsMenu/*'
  </code></pre>
  
  <p>But when <code>pod spec lint DWActionsMenu.podspec</code> is run, the following error occurs:</p>
  
  <pre><code>-&gt; DWActionsMenu (1.0.1)
  - ERROR | [iOS] [xcodebuild]  DWActionsMenu/DWActionsMenu/DWActionButton.swift
  :44:51: error: use of unresolved identifier 'Constants'
  </code></pre>
  
  <p>The situation is, my code runs <strong>correctly</strong> on my phone. <code>Constants</code> is a struct defined in <code>ActionsMenuConstants.swift</code> file.</p>
  
  <p>This is what <code>ActionsMenuConstants.swift</code> looks like:</p>
  
  <pre><code>struct Constants{
      static let kBUTTONSIZE : CGFloat = 44.0
      //......
      static let kMENUHEIGHT : CGFloat = 44.0
  }
  </code></pre>
  
  <p>That's all it has.</p>
  
  <p>So <code>pod spec lint</code> just simply ignored my <code>Constants</code> struct in a separate file????? </p>
  
  <p>How to solve it?</p>