hi, new to kotlin and playing with inline classes ...

# announcements

[Peter]

hi, new to kotlin and playing with inline classes as a replacement for value classes

inline class TypesafeId<T>(val id: Int)

typealias PersonId = TypesafeId<Person>
data class Person(val id: PersonId)

typealias AnimalId = TypesafeId<Animal>
data class Animal(val id: AnimalId)

fun main(args: Array<String>) {
  println(Animal(AnimalId(1)))
  // println(Person(AnimalId(1))) typecheck fails at compile time 
  println(Person(TypesafeId(1)))
}

wondering why the last println compiles successfully?

[Zach Klippenstein (he/him) [MOD]]

The third line in your main function works because the compiler is inferring the T of TypesafeId to be Person.

[Peter]

ahhh ok thanks

[David Eriksson]

#getting-started