I couldn’t find anything but is there a way to assign to itself in the constructor of a class ? For...

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[Antoine Gagnon]

I couldn’t find anything but is there a way to assign to itself in the constructor of a class ?

For the sake of simplification let’s say I have

class Dog{
    val name:String
    val age:Int

    init { this = fetchDogFromSomewhere() }
}

fun fetchDogFromSomewhere():Dog{ 
   // Things
}

Is there some way to achieve this? Right now I’m using a companion method that calls fetchDogFromSomwhere

[Shawn]

🚨 I’m getting some big X-Y problem vibes from this question

[Shawn]

what are you trying to achieve by reassigning the value of this

[Shawn]

sounds almost like you have a singleton? like you only want one instance of Dog and you’d like for folks to receive the same instance if they try to instantiate one?

[Casey Brooks]

If it actually gets instantiated in the constructor, how would the first instance ever be able to be created? It’s a chicken-and-egg problem.

[Casey Brooks]

You could give the appearance of invoking a constructor with operator fun invoke() in the companion object, which is about as good as you could get https://pl.kotl.in/EV4wuPggt

[Shawn]

true, if you just want a factory method to be responsible for instantiation, make the constructor private and implement the method in the companion object - whether you implement invoke or give it a more descriptive name is up to you

[Jakub Pi]

You'll need to be clearer about your objectives. Is there only one instance of Dog for the whole of your program? That's a singleton. Are you trying to potentially return a subclass of Dog? That's an abstract factory. Is there a network request that is serializing your object? You may need to dig down into things like readResolve.. Not sure if that one is applicable to Kotlin though.