转载：深入理解Scala的隐式转换系统

scala> def person(implicit name : String) = name   //name为隐式参数
person: (implicit name: String)String

scala> person
<console>:9: error: could not find implicit value for parameter name: String
              person
              ^

scala> implicit val p = "mobin"   //p被称为隐式值
p: String = mobin
scala> person
res1: String = mobin

scala> implicit val p1 = "mobin1"
p1: String = mobin1
scala> person
<console>:11: error: ambiguous implicit values:
 both value p of type => String
 and value p1 of type => String
 match expected type String
              person
              ^

scala> def foo(msg : String) = println(msg)
foo: (msg: String)Unit
 
scala> foo(10)
<console>:11: error: type mismatch;
found : Int(10)
required: String
foo(10)
^

scala> implicit def intToString(x : Int) = x.toString
intToString: (x: Int)String
 
scala> foo(10)
10

class SwingType{
  def  wantLearned(sw : String) = println("兔子已经学会了"+sw)
}
object swimming{
  implicit def learningType(s : AminalType) = new SwingType
}
class AminalType
object AminalType extends  App{
  import com.mobin.scala.Scalaimplicit.swimming._
  val rabbit = new AminalType
    rabbit.wantLearned("breaststroke")         //蛙泳
}

class SwingType{
  def  wantLearned(sw : String) = println("兔子已经学会了"+sw)
}

package swimmingPage{
object swimming{
  implicit def learningType(s : AminalType) = new SwingType  //将转换函数定义在包中
  }
}
class AminalType
object AminalType extends  App{
  import com.mobin.scala.Scalaimplicit.swimmingPage.swimming._  //使用时显示的导入
  val rabbit = new AminalType
    rabbit.wantLearned("breaststroke")         //蛙泳
}

object Stringutils {
  implicit class StringImprovement(val s : String){   //隐式类
      def increment = s.map(x => (x +1).toChar)
  }
}
object  Main extends  App{
  import com.mobin.scala.implicitPackage.Stringutils._
  println("mobin".increment)
}