is there some way to get the result of a function call into a const val ? some sort of pure function annotation that allows it to be executed at compiletime ?

Kotlin doesn't have a concept of a "pure function", or a way to execute functions at compile time. How can you execute it before compiling it?

compile-time function execution is a pretty common thing

According to the roadmap given by Andrey in the keynote at kotlinconf, there'll be an API for compiler plugins sometime in the future...

Oh, I didn’t even know Scala had macros lol

If there's a programming language feature, it's a pretty safe default to assume Scala has it... :troll:

well could potentially shim it by making a gradle plugin that uses kotlinpoet and creates a new sourceset

Yes, many languages do it with some sort of macro system, but that's arguably a separate "pre-compilation" step and not at compile-time. Technically the JVM has it to some degree with annotations and code generation.

well i'd reall like to have that to inline some string concat or other and have them be

const

for other usecases (and i know string interpolation works but apparently not if done in a method to avoid copypasta

There's a feature request about that: https://youtrack.jetbrains.com/issue/KT-14652