I'm missing a fundamental bit of Kotlin knowledge ...

# tornadofx

[kastork]

I'm missing a fundamental bit of Kotlin knowledge heres. This will not compile - the message is "Type checking has run into a recursive problem. The easiest workaround is to specify the types of your declarations explicitly."

Two questions:
1. What's the second easiest workaround?
2. What would I apply types to? (explicitly stating the type of child doesn't fix it.)

Recursive_type_inference_question.kt