From f42c55de0a214bcd6e604be55a8be1e84dd877cb Mon Sep 17 00:00:00 2001
From: Daniel Firth <dan.firth@homotopic.tech>
Date: Fri, 13 Oct 2023 11:44:46 +0000
Subject: [PATCH] polysemy-plugin: compatibility with ghc 9.8

---
 polysemy-plugin/src/Polysemy/Plugin/Fundep.hs | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/polysemy-plugin/src/Polysemy/Plugin/Fundep.hs b/polysemy-plugin/src/Polysemy/Plugin/Fundep.hs
index 691fcda6..06d48860 100644
--- a/polysemy-plugin/src/Polysemy/Plugin/Fundep.hs
+++ b/polysemy-plugin/src/Polysemy/Plugin/Fundep.hs
@@ -143,7 +143,11 @@ instance Outputable FindConstraint where
 -- | Given a list of constraints, filter out the 'FindConstraint's.
 getFindConstraints :: PolysemyStuff 'Things -> [Ct] -> [FindConstraint]
 getFindConstraints (findClass -> cls) cts = do
+#if MIN_VERSION_GLASGOW_HASKELL(9,8,0,0)
+  cd@(CDictCan(DictCt{di_cls = cls', di_tys = [eff, r]})) <- cts
+#else
   cd@CDictCan{cc_class = cls', cc_tyargs = [eff, r]} <- cts
+#endif
   guard $ cls == cls'
   pure $ FindConstraint
     { fcLoc = ctLoc cd
@@ -157,7 +161,11 @@ getFindConstraints (findClass -> cls) cts = do
 -- | Get evidence in scope that aren't the 'FindConstraint's.
 getExtraEvidence :: PolysemyStuff 'Things -> [Ct] -> [PredType]
 getExtraEvidence things cts = do
+#if MIN_VERSION_GLASGOW_HASKELL(9,8,0,0)
+  CDictCan(DictCt{di_cls = cls, di_tys = as}) <- cts
+#else
   CDictCan{cc_class = cls, cc_tyargs = as} <- cts
+#endif
   guard $ cls /= findClass things
   pure $ mkAppTys (mkTyConTy $ classTyCon cls) as