WIP: Nightly version of Effekt

[jiribenes]

Goal: Add a nightly version of Effekt compiled straight from the effekt-lang/effekt repository.

Current state: Fails with an Scala 3 compiler crash:

 unhandled exception while running genBCode on /build/effekt-with-kiama/effekt/shared/src/main/scala/effekt/util/Control.scala

  An unhandled exception was thrown in the compiler.
        during phase: <no phase>
                mode: Mode(ImplicitsEnabled,ReadPositions)
     library version: version 2.13.10
    compiler version: version 3.3.1
            settings: [ ... ]
                tree: EmptyTree
       tree position: :<unknown>
           tree type: <notype>
              symbol: val <none>
           call site: package <root> in module class <root>
  == Source file context for tree position ==

Error:  ## Exception when compiling 111 sources to /build/effekt-with-kiama/effekt/jvm/target/scala-3.3.1/classes
Error:  java.nio.file.InvalidPathException: Malformed input or input contains unmappable characters: package$?.class

I spent a lot of time debugging this in #2, but I'm lost -- if you know how to fix this / how to progress with this, please let me know!

[jiribenes]

👀 TODO: Take a look at the way lexa packages "latest" Effekt: https://github.com/lexa-lang/lexa/blob/main/nix/effekt_latest.nix

[jiribenes]

Still crashes with more-or-less the same error message.
Could we perhaps try to monkeypatch the Scala version to a higher one? 🤔

[jiribenes]

All versions work for me locally.
This old version https://github.com/jiribenes/effekt-nix/blob/0d249145a6be8be6e4997d571cf676028f87d69d/effekt-nightly.nix also used to work, maybe there's something important there that I overlooked?

[jiribenes]

Interesting! The last commit seems to have reverted to the package$? issue, but the one before it seems to have worked a bit more (getting stuck on missing Scala 3.3.3 compiler)