Kotlin primary and secondary constructors during inheritance

Question

I am learning Kotlin and I'm kind of stuck with the constructors. I've written a program to help me understand the concept. The program is as follows:

open class Animal(){
    var name :String = "noname";
    constructor(name:String):this(){
        this.name = name
    }
    open fun eat(){
        println("$name the animal is eating")
    }
}
class Dog: Animal{
    constructor():super()
    constructor(name : String):super(name)
    override fun eat(){
        println("$name the dog is eating")
    }
}
fun main (args:Array<String>){
    var a1 = Animal("foo")
    var a2 = Animal()
    var d1 = Dog("bar")
    var d2 = Dog()
    a1.eat()
    a2.eat()
    d1.eat()
    d2.eat()
}

Is it possible to modify the program so that the child class calls the parent's primary constructor without using another secondary constructor.
What I'm trying to achieve here is to not force the user to pass a parameter while creating objects using primary and secondary constructors.

Please forgive me if my question is dumb. I am novice here.

Answer 1

In Kotlin, you can set the default value in the constructor itself:

open class Animal(var name: String = "noname"){
    open fun eat(){
        println("$name the animal is eating")
    }
}
class Dog(name: String = "noname"): Animal(name){
    override fun eat(){
        println("$name the dog is eating")
    }
}

This way, "noname" is assigned if no string is provided when invoking the constructor. Also, when you create a Dog object, it will always call the parent constructor.