title: Trying to print object description in Xcode produces an Error
body: <p>I have an objective-C object that we can call ObjCObj
  I implemented a simple description method that usually works perfectly fine if I instanciate the class in a local variable.</p>
  
  <p>The problem:
  I iterate through an array of ObjCObj objects and put them into a Swift Array </p>
  
  <pre><code>let cacheArray = [ObjCObj]()
  </code></pre>
  
  <p>After my array is filled, I try set a breakpoint, try to print the value of an Item and I get the following error:</p>
  
  <pre><code>expression produced error: 
  
  /var/folders/w9/3rvg1bk95379dgvcr11n16_h0000gp/T/lldb/3499/expr878.swift:1:46: error: use of undeclared type '__ObjC'
  $__lldb__DumpForDebugger(Swift.UnsafePointer&lt;__ObjC.ObjCObj&gt;(bitPattern: 0x67fd9b0).memory)
  </code></pre>
  
  <p>If I try to print an Expression like:</p>
  
  <pre><code>cacheArray[2]
  </code></pre>
  
  <p>It works. But If I open the array in the debugger inspector and choose one line of the array and ask for printing the description, it fails.</p>