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kotlinlang

Is there any way to get kotlin property's default value?

i mean
```
data class Test(val x:String="I'm default")
```

How do I get "I'm default" from KProperty1&lt;Test,String&gt; ?

Ah, this is reflection territory. I'm not sure how but you can get it via reflection.

Ah! `x` property does not have a default value!

But `x` constructor parameter has a default value.

I need it in JS to handle undefined states...

Reflection is JS is not possible generally

The problem is that default values are actually full pieces of code, for example:
```
fun foo(x: List&lt;Int&gt; = listOf(1, 2, 3)) {}
```
You can't really get a default value from that, it's an expression that needs to be evaluated every time.

Even worse, you can have this:
```fun foo(x: Int, y: Int = x+1)```

That's good to know actually, and yes that's a lot worse!