title: Use of undeclared identifier when I want use swift file in objective c project
body: <p>when I want use swift file in objective c project and I declare an object from swift class, I get "Use of undeclared identifier" error.
  the way that I pass:</p>
  
  <ol>
  <li><p>coping swift file in project and type <strong>@objc</strong> before declare swift class</p></li>
  <li><p>create header file in project manually</p></li>
  <li><p>set "<strong>Defines module</strong>" in target to <strong>Yes</strong></p></li>
  <li><p>set <strong>objective-C bridging header</strong> in <strong>target</strong> to <strong>$(SRCROOT)/$(PRODUCT_MODULE_NAME)-Bridging-Header.h</strong> </p></li>
  <li><p>declare <strong>#import "productModuleName-Bridging-Header.h"</strong> in objective-c file</p></li>
  <li><p>use <strong>name_of_swift_class *s = [[name_of_swift_class alloc] init];</strong></p></li>
  </ol>
  
  <p>when I want use swift file in step 6 I get "Use of undeclared identifier" error. why?!!! do I have the mistake?</p>
  
  <p>when I test this steps in new project I don't get error but in project that I want it return error.</p>
  
  <p>thank you for your help</p>