Kotlin : Why unresolved reference for a constructor parameter of a subclass of a sealed class

Question

sealed class Person () {
    data class Man (val name: String): Person()
    data class Woman (val name: String): Person() 

    fun stringOf(): String {
    return when (this) {
        is Person.Man -> "Mr "+this.name
        is Person.Woman -> "Mrs "+this.name
    }
    } // works fine

    fun nameOf() : String {
        return this.name // error: unresolved reference: name
    }
}

fun main(args: Array<String>) {
    val man = Person.Man("John Smith")
    println (man.stringOf()) 
}

Why the code above gives error: unresolved reference: name for the function nameOf and works correctly for function stringOf which looks very similar.

Because it is not smart-casted to an actual type that actually has `name`. Why not move it to `Person`? — EpicPandaForce, Feb 29 '20 at 16:14
@EpicPandaForce I want to get *name* constructor of the data classes, the sealed class has no constructor. — Emile Achadde, Feb 29 '20 at 16:21

score 2 · Accepted Answer · answered Feb 29 '20 at 19:00

2

Because no name property is defined in Person class. All names you have are in subclasses, so nameOf function in the parent class cannot access it.

answered Feb 29 '20 at 19:00

madhead

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Kotlin : Why *unresolved reference* for a constructor parameter of a subclass of a sealed class

1 Answers1

Kotlin : Why unresolved reference for a constructor parameter of a subclass of a sealed class