     - parameter operation: the `Operation` which has started.
     */
     public func operationDidStart(operation: Operation) {
-        log("\(operationName(operation)): did start.")
+        log("\(operation.operationName): did start.")
     }
 
     /**

    */
    public func operationDidFinish(operation: Operation, errors: [ErrorType]) {
        let detail = errors.count > 0 ? "error(s): \(errors)" : "no errors"
        log("\(operationName(operation)): finished with \(detail).")
    }

    private func operationName(operation: Operation) -> String {
        if let name = operation.name {
            return "\(name)"
        }
        return "\(operation)"
    }

    private func log(message: String) {

     - parameter operation: the `Operation` which has started.
     */
    public func operationDidCancel(operation: Operation) {
        log("\(operation.operationName): did cancel.")
    }

    /**
