title: cannot print a variable in swift
body: <p>I wrote the code that is shown below. How can I print A4 variable?
  When I try like that I get an error?</p>
  
  <p>Error: __lldb_expr_1.Paper</p>
  
  <pre><code>// Paper Factory
  // All sizes are mm type
  import UIKit
  
  
  class Paper {
      var weight: Double = 0.0
      var sizeHeight: Double = 0.0
      var sizeWidth:  Double = 0.0
  
      init(weight: Double, sizeHeight: Double, sizeWidth: Double){
          self.sizeHeight = sizeHeight
          self.sizeWidth = sizeWidth
          self.weight = weight
      }
  
      func paperPrice(weight: Double, sizeHeight:Double, sizeWidth:Double){
          var price = (sizeHeight * sizeWidth) * weight / 1000
      }
  }
  
  var A4 = Paper(weight: 3, sizeHeight: 210, sizeWidth: 297)
  
  println(A4)
  </code></pre>