THE ORIGINAL FEATURE REQUEST by @Damian Wieczorek: This can be extremely useful when dealing with third-party libraries or frameworks which require extending their own classes. Currently, the common thing to do is implement them within an interface that must be implemented in each class. For example (in Android), to create an extension function "Float.dp()" to use within a "View": fun (View, Float).dp() = this * resources.displayMetrics.density // explicitly: fun (View, Float).dp() = this@Float * this@View.resources.displayMetrics.density class SomeView : View { val someDimension = 4f.dp() } UPDATE by @Roman Elizarov: The problem that this issue describes is important, even though this particular proposed syntax is quite alien with respect to Kotlin traditions. We are prototyping different syntactic approaches to make it work so that you could define this kind of multiple-receiver extensions. Basics The primary model and inspiration for this feature is Kotlin's member extension functions that have two receivers:…