Initiation of val in data class

[meriah]

I have a class that takes one variable and treats it a little for further storage. I'd like to have a variable. value int all functions data class (whispers) equals and hashCode should only be new. value)

data class GF(var value: Int = 0) {
init {
    value = value % 10
}

}

I tried to do this:

data class GF {

val value: Int

constructor(data: Int = 0) {
    value = data % 10
}

}

However, I get: Data class must have at least one primary constructor parameter

[Raziyah00]

Make a field in the designer private and add another field. value In your class:

data class GF(private var data: Int) {
    val value: Int
init {
    data %= 10
    value = data
}

}

Thus, equals and hashCode will use the updated value. C copy There's no problem either.