fix compilation with older GHC versions

2022-11-10 19:19:19 +01:00
parent 5ca00ded84
commit 9214f2a074
2 changed files with 9 additions and 1 deletions
--- a/src/compiler/GF/Compile/Compute/Concrete.hs
+++ b/src/compiler/GF/Compile/Compute/Concrete.hs
@@ -584,11 +584,19 @@ instance Functor ConstValue where
 instance Applicative ConstValue where
  pure = Const

+  (Const f) <*> (Const x) = Const (f x)
+  NonExist  <*> _         = NonExist
+  _         <*> NonExist  = NonExist
+  RunTime   <*>  _        = RunTime
+  _         <*>  RunTime  = RunTime
+
+#if MIN_VERSION_base(4,10,0)
  liftA2 f (Const a) (Const b) = Const (f a b)
  liftA2 f NonExist  _         = NonExist
  liftA2 f _         NonExist  = NonExist
  liftA2 f RunTime   _         = RunTime
  liftA2 f _         RunTime   = RunTime
+#endif

 value2string v = fmap (unwords.snd) (value2string v False [])
  where