http://blog.csdn.net/shenlanzifa/article/details/42679577
http://alvinalexander.com/java/jwarehouse/scala-2.11/library/scala/annotation/implicitNotFound.scala.shtml
http://blog.csdn.net/shenlanzifa/article/details/42679577
http://alvinalexander.com/java/jwarehouse/scala-2.11/library/scala/annotation/implicitNotFound.scala.shtml