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kotlinlang

Screenshot 2022-09-26 at 19.54.16.png

Because your `on` function is not inline, that lambda is considered as a closure, and because closure is self-contained, it must "capture" stuff in the outer scope, and now that it's not possible to directly modify a local variable in a closure, that local is wrapped into an object with a var member for the closure to "modify".

either `inline` your on function or rather just ignore it

```inline fun &lt;reified T : Event&gt; EvenTester.on(
    crossinline consumer: suspend Event.(T) -&gt; Unit
): EventListener {
    return object : EventListener {
            override suspend fun onEvent(event: Event) {
                if (event is T) {
                    event.consumer(event)
                }
            }
        }
        .also { this.addEvent(it) }
}```

Sorry for the delay. Because `consumer` is crossinline, anything inside it should be captured to be used in this `EventListener` object, so `consumer` is effectively closure. You need to ignore that "Captured..." info then. To be honest this is not a big deal.