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kotlinlang

I see <https://youtrack.jetbrains.com/issue/KT-79394> is implemented in Kotlin 2.2.20-Beta2.
Is there any examples how to use it?

I've just used it inside kotlinx.browser, you can take a look: <https://github.com/Kotlin/kotlinx-browser/tree/master/src/webMain/kotlin/org.w3c>

The idea was quite simple: you can just move your declarations from `wasmJsMain` to `webMain` and it could be compiled to both wasmJs and JS targets (the only limination, that for declarations under kotlin.js package you need manually to add imports)

<@U02BK8ABTQF> thanks for great work! But i have one more question, if i'm not using applyDefaultHierarchyTemplate(), how should i define webMain and webTest source sets?
Now i'm just creating them with such names and make depend on it from js and wasmJs targets souresets, but got compilation error for wasmJs target
```import kotlinx.browser.window
import org.w3c.dom.url.URLSearchParams

URLSearchParams(window.location.search) // Argument type mismatch: actual type is 'String', but 'JsAny?' was expected.```
wasmJs sourceSet have also org.jetbrains.kotlinx:kotlinx-browser dependency
js target compiles successfully

Solved! If i convert toJsString() it compiles ok for both targets
```URLSearchParams(window.location.search.toJsString())```


Yes, you can. And the most valuable thing there that for JS target all the convertions to JsSomething and back are zero-cost abstractions (it just re-use the value itself)

Or you can use Kotlin Wrappers, where such conversions <https://github.com/JetBrains/kotlin-wrappers/blob/b359a3699e754ac5ac582d100fc8be89e5e3372c/kotlin-web/src/commonMain/generated/web/url/URLSearchParams.kt#L22|aren't required>. :wink:

Thanks, <@U33H6SB2B>! But i prefer kotlinx-browser cause it just externals for browser api.

&gt; cause it just externals for browser api
It's what <https://github.com/JetBrains/kotlin-wrappers/tree/master/kotlin-browser|kotlin-browser> is :wink:
With 100% of stable API support.

Now i'm confused! Why there are two official JetBrains libraries then?

<https://kotlinlang.slack.com/archives/C0B8L3U69/p1752350124488019?thread_ts=1752333105.914149&amp;cid=C0B8L3U69|Answer>

Thanks! But i still can't understand what breaking changes could be for kotlin-browser if it is just externals for stable browser api? By stable browser api i mean w3c standarts. If they will be changing then both libs should follow.

Short example:
```// non-strict 
external A(
   p: Any // String | Double | Boolean 
)

// strict 
external A(
   p: String 
) {
   constructor(p: Double)
   constructor(p: Boolean)
}```
Let's deprecate constructor with `Boolean` parameter :wink:

```// non-strict 
// No breaking change
external A(
   p: Any // String | Double
)

// strict 
external A(
   p: String 
) {
   constructor(p: Double)
   // BREAKING CHANGE 
   // constructor(p: Boolean)
}```


More strictness -> more breaking changes :disappointed:

And common `kotlin-browser` is already available. :wink:
You can use it with Kotlin `2.2.0`

<@U33H6SB2B> what about performance and code size comparison?