@bjonnh I can’t tell the full context from what you posted (is this just the Boolean implementation? Or is the presence of

Boolean

in your code because the function must always deal with Boolean no matter which type of Term?) Assuming the pastebin contains the Output that only deals with Boolean, then why not

class Output<U: Term<V>, V>(val name: String) {
   private val callbacks: MutableList<suspend (U) -> V> = mutableListOf()
   // ...
}

and then have

class Term

be

class Term<V>

instead? I’m a relative neophyte with generics, though, so could be wrong. Plus I don’t have all your code, so maybe my suggestion doesn’t work anyway.

V can be Int, Double, Pair, and any custom thing I make

OK so what’s wrong with what you pasted in Pastebin?

I had issues with the type inference, sorry I should have killed my question.