Hi Is there a way to make data classes with default parameter values work properly in Swift? Example...

# multiplatform

[Artur Matsehor]

Hi
Is there a way to make data classes with default parameter values work properly in Swift?
Example:

data class State @JvmOverloads constructor(
    val loading: Boolean = false,
    val data: ResponseBody? = null,
    val error: ApiError? = null
)

In Swift, it is resolved to
init(loading: Bool, data: ResponseBody?, error: ApiError?)
Neither with overloads or default values

[dazza5000]

Are you creating a framework?

[Madhan]

@Artur Matsehor I'm also facing same problem.
In Xcode it throws error as "init is unavailable".

let me know if you found solution for this.
Thanks in advance

[Artur Matsehor]

@dazza5000 yes

[Artur Matsehor]

Basically, I'm making a project with business-logic written in Kotlin, leaving only UI and VMs on a platform side. Pretty usual case for KMP, as I understand.

[Artur Matsehor]

@Madhan now I kinda solve it by creating functions like
*func* State(loading: Bool = *false*, data: ResponseBody? = *nil*, error: ApiError? = *nil*) -> State {
  .init(loading: loading, data: data, error: error)
}

Which is against Swift conventions and is a boilerplate, but still better than nothing

[Madhan]

Okay @Artur Matsehor , But Here is my suggestions

class State {
    var loading: Boolean = false,
    var data: ResponseBody? = null,
    var error: ApiError? = null

    constructor()

    constructor(loading: Boolean = false,
                 data: ResponseBody? = null,
                 error: ApiError? = null) {
        this.loading = loading
        this.data = data
        this.error = error
    }
}

Look into it and let me know your thoughts

[Artur Matsehor]

Legit, but still a part of a solution
Say, I need a let state = State(data: responseData) - it is still impossible(
Also, here we're losing all the data class sweeties, like toString(), hashCode(), componentN(), etc

[Artur Matsehor]

I'm really thinking of making a Gradle plugin that generates all the constructor overloads before converting a class into a Swift framework

[Artur Matsehor]

@Madhan you can watch this issue on Youtrack also
https://youtrack.jetbrains.com/issue/KT-38685

[Madhan]

sure @Artur Matsehor ,thanks for sharing