Pattern for Union of Value Types

class T private constructor(private val value: Value) {
    sealed class Value {
        data class IntValue(val int: Int) : Value()
        data class BoolValue(val bool: Boolean) : Value()
    }

    companion object {
        fun fromInt(int: Int): T = T(Value.IntValue(int))
        fun fromBoolean(bool: Boolean): T = T(Value.BoolValue(bool))
    }

    override fun toString(): String = when (value) {
        is Value.IntValue -> value.int.toString()
        is Value.BoolValue -> value.bool.toString()
    }
}