Scala入门05

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作为笔记记录下：

package com.lijie.scalaimport MyImpilicit.person2Comp//视图界定 需要隐式转换 这里传入的T必须隐式转换成Ordered的类型class MyComparctorOrdered[T <% Ordered[T]] {  def comp(t1: T, t2: T): T = {    if (t1 > t2) t1 else t2  }}object MyComparctorOrdered {  def main(args: Array[String]): Unit = {    val c = new MyComparctorOrdered[Person]    val p1 = new Person("lijie01", 24)    val p2 = new Person("lijie02", 25)    println(c.comp(p1, p2).name)  }}

package com.lijie.scalaimport MyImpilicit._//上下文界定class MyComparctorOrdering[T: Ordering] {  def comp(t1: T, t2: T): T = {    val p = implicitly[Ordering[T]]    if (p.gt(t1, t2)) t1 else t2  }}object MyComparctorOrdering {  def main(args: Array[String]): Unit = {    val c = new MyComparctorOrdering[Person]    val p1 = new Person("lijie01", 24)    val p2 = new Person("lijie02", 25)    println(c.comp(p1, p2).name)  }}

package com.lijie.scalaobject MyImpilicit {  implicit def person2Comp(p: Person) = new Ordered[Person] {    override def compare(that: Person) = {      p.age - that.age    }  }  implicit val person2Comp = new Ordering[Person] {    override def compare(a: Person, b: Person) = {      a.age - b.age    }  }}

package com.lijie.scalaclass Person(val name: String, var age: Int)

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