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Kotlin variable initialization for child class behaves weird for initializing va...

 4 years ago
source link: https://stackoverflow.com/questions/59822125/kotlin-variable-initialization-for-child-class-behaves-weird-for-initializing-va
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Kotlin variable initialization for child class behaves weird for initializing variable with value 0

I have created the following class hierarchy:

open class A {
    init {
        f()
    }

    open fun f() {
        println("In A f")
    }
}

class B : A() {
    var x: Int = 33

    init {
        println("x: " + x)
    }

    override fun f() {
        x = 1
        println("x in f: "+ x)
    }

    init {
        println("x2: " + x)
    }
}

fun main() {
    println("Hello World!!")
    val b = B()
    println("in main x : " + b.x)
}

The output of this code is

Hello World!!
x in f: 1
x: 33
x2: 33
in main x : 33

But if I change the initialization of x from

var x: Int = 33

var x: Int = 0

the output shows the invocation of the method in contrast to the output above:

Hello World!!
x in f: 1
x: 1
x2: 1
in main x : 1

Does anyone know why the initialization with 0 causes a different behaviour than the one with another value?


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