Extension functions on annotated types

Is it possible to define a Kotlin extension function on a annotated type like this?

@ColorInt
fun @ColorInt Int.darken(): Int {
return ColorUtils.blendARGB(this, Color.BLACK, 0.2f)
}

Alternative form:

@ColorInt
fun (@ColorInt Int).darken(): Int {
return ColorUtils.blendARGB(this, Color.BLACK, 0.2f)
}


That would correspond to the following static funtion:

@ColorInt
fun darken(@ColorInt color: Int): Int {
return ColorUtils.blendARGB(color, Color.BLACK, 0.2f)
}

I don't think that's possible yet using Kotlin, but would it be possible to add that feature in later Kotlin versions?

On a side note:
The same question applies to `@IntDef`, `@StringDef`, `@[resource type]Res` as well.

Yes you can. Use the following syntax:

@ColorInt
fun @receiver:ColorInt Int.darken(): Int {
return ColorUtils.blendARGB(this, Color.BLACK, 0.2f)
}

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