部分参数应用函数

scala> def m(a: Int, b: Int) = a + b
m: (a: Int, b: Int)Int

scala> m(1, _: Int)
res0: Int => Int = <function1>

scala> def partM = m(1, _: Int)
partM: Int => Int

scala> partM(13)
res1: Int = 14

scala> val partM = m(3, _:Int)
partM: Int => Int = <function1>

scala> partM(10)
res3: Int = 13

Idea中实现

package day02

import java.util.Date

object PartParamFunc extends App {
  //定义个输出的方法，参数为date，message
  def log(data: Date, message: String) = {
    println(s"$data, $message")
  }

  val date = new Date()
  val logBoundDate = log(date, _: String)

  log(date, "hello")
  logBoundDate("hello")

}