Support (in theory) GHC 9.6

[chrisdone]

@juhp I'm not sure why Control.Monad is needed -- I'd prefer to just add an explicit import. Let me know if there's a specific name that isn't available anymore.

I'll need more time than a 5 min fix to upgrade my CI from GHC 9.4.8 to 9.6, so in the interim I don't mind throwing a CPP on there for the newer versions.

[juhp]

Thanks

Anyway this is what I prepared before realising you already committed:

modified   src/Hell.hs
@@ -12,6 +12,7 @@
 {-# LANGUAGE GADTs, PolyKinds, TupleSections, StandaloneDeriving, Rank2Types, FlexibleContexts #-}
 {-# LANGUAGE ViewPatterns, LambdaCase, ScopedTypeVariables, PatternSynonyms, TemplateHaskell #-}
 {-# LANGUAGE OverloadedRecordDot, OverloadedStrings, MultiWayIf, DeriveFunctor, DeriveFoldable, DeriveTraversable, TypeOperators, UndecidableInstances, TypeFamilies, AllowAmbiguousTypes, MultiParamTypeClasses, FlexibleInstances, ExtendedDefaultRules #-}
+{-# LANGUAGE CPP #-}
 
 module Main (main) where
 
@@ -66,7 +67,9 @@ import qualified Options.Applicative as Options
 import Data.Traversable
 import Data.Bifunctor
 import System.Process.Typed as Process
-import Control.Monad
+#if MIN_VERSION_base(4,18,0)
+import Control.Monad (foldM, when)
+#endif
 import Control.Monad.State.Strict
 import Control.Monad.Reader
 import System.Environment
@@ -76,7 +79,10 @@ import Data.Vector (Vector)
 import Data.Aeson (Value)
 import Data.Text (Text)
 import Data.ByteString (ByteString)
-import GHC.Types hiding (List)
+import GHC.Types
+#if MIN_VERSION_ghc_prim(0,10,0)
+  hiding (List)
+#endif
 import GHC.TypeLits
 import Type.Reflection (SomeTypeRep(..), TypeRep, typeRepKind, typeRep, pattern TypeRep)

I think yours works - will try later, though conditioning on the library versions might be more precise.

It is fairly easy to test locally: stack --resolver lts-22 install