     }
 
     func printTopOfStackPrim() {
-        print("\(self.pop().description()) ")
+        print("\(self.pop()) ")
         self.next()
     }
 

    case Variable(address: Int)
    case Constant(value: Int)

    func description() -> String {
        switch self {
        case let .Thread(index):
            return "Thread(\(index))"


import Foundation

enum Cell: Printable {
    case Thread(index: Int)
    case Primitive(num: Int)
    case Literal(value: Int)
