       if let message: Int = selection.getData() { i++ }
     }
 
-    //    syncprint("\(i) messages received")
     syncprintwait()
     
-    XCTAssert(i == iterations, "incorrect number of messages received")
+    XCTAssert(i == iterations, "Received \(i) messages; expected \(iterations)")
   }
 
   func testPerformanceSelectBufferedReceiver()

    let selectableCount = 10
    let iterations = sleepInterval < 0 ? 10_000 : 100

    let channels  = map(0..<selectableCount) { _ in Chan<Int>.Make(buffered ? 1 : 0) }
//    let channels  = [Chan<Int>](count: selectableCount, repeatedValue: Chan<Int>.Make(buffered ? 1 : 0))
    let senders   = channels.map { Sender($0) }
    let receivers = channels.map { Receiver($0) }


        let index = Int(arc4random_uniform(UInt32(senders.count)))
        senders[index] <- i
      }
      NSThread.sleepForTimeInterval(sleepInterval > 0 ? sleepInterval : 1e-6)
      for sender in senders { sender.close() }
    }

