Scala example source code file (ArrowUsage.scala)

This example Scala source code file (ArrowUsage.scala) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Scala by Example" ^TM.

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Java - Scala tags/keywords

app, arrowusage, int, string

The ArrowUsage.scala Scala example source code

package scalaz.example

import scalaz._

object ArrowUsage extends App {

  import Scalaz._

  val plus1 = (_: Int) + 1
  val times2 = (_: Int) * 2
  val rev = (_: String) reverse

  // Function1 arrow

  // Applying first on the Function1 arrow.
  (plus1.first apply (7, "abc")) assert_=== (8, "abc")

  // Applying second on the Function1 arrow.
  (plus1.second apply ("def", 14)) assert_=== ("def", 15)

  // Combine plus1 and rev on the Function1 arrow to apply across both elements of a pair.
  (plus1 *** rev apply (7, "abc")) assert_=== (8, "cba")

  // Perform both plus1 and times2 on a value using the Function1 arrow
  (plus1 &&& times2 apply 7) assert_=== (8, 14)

  // Perform plus1 on a pair using the Function1 arrow
  (plus1.product apply (9, 99)) assert_=== (10, 100)

}