CheolhoJeon

package chap5.CompanionObjects

import atomictest.eq

class WithObjectProperty {
  companion object {
    private var n: Int = 0 // Only one
  }
  fun increment() = ++n
}

CheolhoJeon

package chap5.CompanionObjects

import atomictest.eq

class WithNamed {
  companion object Named {
    fun s() = "from Named"
  }
}

CheolhoJeon

package chap5.CompanionObjects

import atomictest.eq

class WithCompanion {
  companion object {
    val i = 3
    fun f() = i * 3
  }
  fun g() = i + f()

CheolhoJeon

package chap5.Object

import atomictest.eq

object Outer {
  object Nested {
    val a = "Outer.Nested.a"
  }
}

CheolhoJeon

package chap5.Object.objectshare2

import atomictest.eq
import chap5.Object.objectshare1.f
import chap5.Object.objectsharing.Shared

fun g() {
  Shared.i += 7
}

CheolhoJeon

package chap5.Object.objectshare1

import chap5.Object.objectsharing.Shared

fun f() {
  Shared.i += 5
}

CheolhoJeon

package chap5.Object.objectsharing

object Shared {
  var i: Int = 0
}

CheolhoJeon

package chap5.Object.objectsharing

object Shared {
  var i: Int = 0
}

CheolhoJeon

package chap5.Object

import atomictest.eq

open class Paint(val color: String) {
  open fun apply() = "Applying $color"
}

object Acrylic: Paint("Blue") {
  override fun apply() = "Acrylic, ${super.apply()}"

CheolhoJeon

package chap5.Object

import atomictest.eq

object JustOne {
  val n = 2
  fun f() = n * 10
  fun g() = this.n * 20   // [1]
}