Look at the following code:

abstract class A {

    init {
        f()
    }

    abstract fun f()
}

class B(val p: () -> Unit) : A() {

    override fun f() {
        try {
            p()
        } catch (c: Throwable) {
            println(c)
        }
    }
}

val b = B {
    println("p() called")
}

Expecting p() called will be printed, actual result is NPE:

java.lang.NullPointerException: Cannot invoke "kotlin.jvm.functions.Function0.invoke()" because "this.p" is null

Could you please explain, why can’t I access child constructor parameter from parent’s constructor? And how can I deal with this?