<@U2SG23BPU> <@UKPEELJCW> or others that may know,...

# arrow-meta

[raulraja]

@dsavvinov @dmitriy.novozhilov or others that may know, I’m implementing the KEEP-87 as a compiler plugin to see if its possible in arrow meta.
I’m attempting currently to get a hold of the resolver of the function injected with @with to enhance the scope resolution of that function so it takes in account the Semigroup<A> type to resolve combine without the need to wrap the body in with (S) { a.combine(b) }.
What part of the compiler do I need to look into to avoid the unresolved reference: combine?
In the actual Keep impl this happens in the BodyResolver but not sure how to get to that point in a compiler plugin. Any help or pointers in the right direction is appreciated.

[dmitriy.novozhilov]

To provide functionality that you want you need to change context.scope before entering to resolution and inference to new scope with new ownerDescriptor that should be some descriptor with receiver that you want (see CallResolver.java:564)

[dmitriy.novozhilov]

object Contained {
    fun <A> add(S: Semigroup<A>, a: A, b: A): A {
        a.combine(b)  // 1
        with(S) {
            a.combine(b)  // 2
        }
    }
}

For that code for call 1 scope owner is fun add, for call 2 -- fun Semigroup<A>.<anonymous>(). So, for call PsiCallResolver creates ScopeTower (PSICallResolver.kt:91) that looks for functions in appropriate member scopes.

[dmitriy.novozhilov]

But at this moment there is no extension points that can somehow affect resolution and inference algorithm, and I can't help you with that

[raulraja]

thanks so much for the info, I’ll look into it.