Fix bug when deriving instances of Bounded type class

CHANGELOG.md

@@ -11,6 +11,7 @@ Version 1.0.4
 =============
 
   * Fixed bug in type checking of instances
+  * Fixed bugs in deriving of `Bounded` instances.
 
 Version 1.0.3
 =============

src/Checks/InstanceCheck.hs

@@ -196,7 +196,7 @@ bindDerivedInstance clsEnv p tc pty tys cls = do
                                     , (fromEnumId, 1), (enumFromId, 1)
                                     , (enumFromThenId, 2)
                                     ]
-              | cls == qBoundedId = [(maxBoundId, 1), (minBoundId, 1)]
+              | cls == qBoundedId = [(maxBoundId, 0), (minBoundId, 0)]
               | cls == qReadId    = [(readsPrecId, 2)]
               | cls == qShowId    = [(showsPrecId, 2)]
               | otherwise         =

src/Transformations/Derive.hs

@@ -274,8 +274,8 @@ enumFromThenExpr v1 v2 c1 c2 =
 
 deriveBoundedMethods :: Type -> [ConstrInfo] -> PredSet -> DVM [Decl PredType]
 deriveBoundedMethods ty cis ps = sequence
-  [ deriveMaxOrMinBound qMaxBoundId ty (head cis) ps
-  , deriveMaxOrMinBound qMinBoundId ty (last cis) ps
+  [ deriveMaxOrMinBound qMinBoundId ty (head cis) ps
+  , deriveMaxOrMinBound qMaxBoundId ty (last cis) ps
   ]
 
 deriveMaxOrMinBound :: QualIdent -> Type -> ConstrInfo -> PredSet