Functions and Methods

Local Functions

Define a helper inside another method.

local-functions A local function belongs to the block where it is defined. It keeps a helper close to the code that uses it.

Local Functions

base
LocalFunctions.scala
Replay: real traced execution (multi-file project)
object Main {
  def main(args: Array[String]): Unit = {
    val base = 3

    def addOne(value: Int): Int = {
      value + 1
    }

    val result = addOne(base)

    println("base=" + base)
    println("result=" + result)
  }
}

object Main {
  def main(args: Array[String]): Unit = {
    val base = 5

    def addOne(value: Int): Int = {
      value + 1
    }

    val result = addOne(base)

    println("base=" + base)
    println("result=" + result)
  }
}

  1. base ← 3

    1object Main {2  def main(args: Array[String]): Unit = {3    val base→ 3 = 3 //@base=545    def addOne(value: Int): Int = {6      value + 17    }89    val result = addOne(base3)1011    println("base=" + base)

  2. def addOne(value: Int): Int =

    5def addOne(value3: Int): Int = {6  value3 + 17}

  3. result ← 4

    9    val result→ 4 = addOne(base3)1011    println("base=" + base3)12    println("result=" + result4)13  }14}
    outputbase=3
result=4

  1. base ← 5

    1object Main {2  def main(args: Array[String]): Unit = {3    val base→ 5 = 545    def addOne(value: Int): Int = {6      value + 17    }89    val result = addOne(base5)1011    println("base=" + base)

  2. def addOne(value: Int): Int =

    5def addOne(value5: Int): Int = {6  value5 + 17}

  3. result ← 6

    9    val result→ 6 = addOne(base5)1011    println("base=" + base5)12    println("result=" + result6)13  }14}
    outputbase=5
result=6