Why cannot I pass a function reference to

Iterable<T>.sortedBy()

?

fun mySort(uiState: UiState): Int = // sort based on some criteria

val uiStates: List<UiState>

uiStates.sortedBy(mySort) // doesn't compile: Function invocation `mySort(...)` expected; No value passed for parameter `uiState`

ok... why a rubber duck emoji? I'm missing a cult reference here. or at least how it applies (I'm running through the James Veitch duck sketch and trying to figure out how that apply here)

It's a debugging technique, where you explain the problem to yourself loud (e.g. talking at a rubber duck) to find a solution: https://en.wikipedia.org/wiki/Rubber_duck_debugging