Primitive properties initialization in Kotlin

Question

I have immutable Int property which value is caclulated in the constructor.Something like this:

class MyClass {
    val myProperty:Int
    init{
        //some calculations
        myProperty=calculatedValue
    }
}

But this code won't compile.Compiler says Property must be initialized or be abstract .I can't initialize it as it's value will be known only after class instantiation.Looks like kotlin forces me to have the property mutable.Is this the only way?
UPD:I just realized I was assigning property value inside for loop which leads to unable to reassign val property error.This topic is subject for deletion.Sorry.

Answer 1

Why not doing it while initialization?

class MyClass {
    val myProperty: Int = calcMyProperty() // use that if the calculation is complex
    val myOtherProperty: Int = 5 + 3 // use that if the calculation is simple

    private fun calcMyProperty(): Int {
        // some very complex calculation
        return 5 + 3
    }
}

Answer 2

You can use the run function. You val will be initialized with the value that is returned from the lambda (the last expression). Like this:

class MyClass {

    val myProperty: Int = run {
        //some calculations
        calculatedValue
    }

}

Answer 3

The acceptable answer is to use private setter:

class MyClass {
    var myProperty:Int=0
       private set
    init{
        //some calculations
        myProperty=calculatedValue
    }
}

However there is still chance to reassign wrong value inside the class