I have a question regarding a Kotlin JS snippet. I...

# javascript

[julien lengrand-lambert]

I have a question regarding a Kotlin JS snippet. It look like my nullable variables become undefined when being used inside my component

data class FirebaseUser(
    val email: String,
    val uid: String,
    val accessToken: String,
)

@JsModule("@jlengrand/firebase-ports")
@JsNonModule
external object FirebasePorts{
    fun logIn() : Promise<FirebaseUser>
}                

var user : FirebaseUser? by mutableStateOf(null)

Button(attrs = {
                    onClick {
                        console.log(JSON.stringify(user))                        
                        console.log(user)
                        console.log(user!!.uid)
                    }
                }) {

When doing this, ths results are as following :

{"accessToken":"exampleToken","email":"<mailto:[e-mail]|[e-mail]>","uid":"example"}
{accessToken:exampleToken,email:[e-mail],uid:example}
undefined

Is that expected, and how do I fix this? I mean, the value is there clearly

[turansky]

external interface FirebaseUser {
    val email: String
    val uid: String
    val accessToken: String
}

[julien lengrand-lambert]

Annnnd bingo

[julien lengrand-lambert]

Ok, ty ^^. Lots of bad habits from Backend kotlin to erase I see. Cheers!

[Big Chungus]

FYI, JSON.stringify should not be used with any non-external kotlin type

[Big Chungus]

The behaviour of doing so is very unpredictable

[turansky]

With ES6 and private properties (in perfect future Kotlin/JS) it must be very predictable and transparent 🙂

cc @Sergei Grishchenko