How to solve: "Conditional branch result is implicitly cast to Any" in streamline-map

Well, I was only responding to the point you raised about contentList being changed to a List<Any> in your original example.

It’s beside the point anyway because what we’re concerned with is the type of List which the map function returns, not the type of List to which this function is applied.

Where we seem to differ is that I think it’s reasonable for the compiler to issue warnings when you’re not explicit about the return type being Any but you don’t?