Is Kotlin's singleton thread-safe?

# getting-started

[tateisu]

Is Kotlin's singleton thread-safe?

[Dominaezzz]

Someone correct me if I'm wrong. On the Native and JS backend it doesn't matter. On the JVM backend, it is the same as Java.

[tateisu]

Java does not provide singleton on language level. what do you saying ?

[tateisu]

also, Kotlin/Native has worker model, but it uses thread in behind. "it doesn't matter" is not correct.

[Alexander Levin]

According documentation, it is.
https://kotlinlang.org/docs/reference/object-declarations.html#object-declarations

For JVM (according decompiled version of simple object), it is initialized in static block and static class init is guaranteed to be thread-safe AFAIK

[Dominaezzz]

By "it doesn't matter", I meant you can't have shared mutable state. So you do not need to think about Thread-safety.

[karelpeeters]

object MyState { var foo = 4 }