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kotlinlang

Can some help me in suggesting how to create a *frozen singleton* that takes in init parameters?

```actual open class SomeClass private constructor(
        private val someProperty: SomeProperty
) {

    actual companion object {
        private var someClass: SomeClass? = null

        fun initialize(someProperty: SomeProperty){
            someClass = SomeClass(someProperty)
        }

        actual fun getInstance(): SomeClass {
            if (someClass == null) {
                throw UninitializedPropertyAccessException("SomeClass is not initialised yet")
            }
            return someClass as SomeClass
        }
    }
}```


This won't work because companion object is immutable and we cant change someClass property in there. Is there any way to get a Frozen Singleton with params?

<https://stackoverflow.com/questions/59484818/kotlin-native-can-some-help-me-in-suggesting-how-to-create-a-frozen-singleton-t>

problem is at which moment you want it to be called, and when make it available. But if you'll change
```someClassAtomicRef.value = someClass.freeze()```
to
```someClassAtomicRef.compareAndSet(null, someClass.freeze())```
then init will happen only once.

ok. got it. the next time, it wont compare to null and hence wont set the variable. thanks

another option is to have regular singleton with custom `init` block which fetches config proactively, like it's done in <https://github.com/JetBrains/kotlin-native/blob/552984758e4992129d791420a1f266b636b8c26e/samples/tetris/src/tetrisMain/kotlin/Config.kt#L19>