Added a helper function like functionOperator, but that only gives back a Just result if the operator is a non-overridden version

checks/Check.hs

@@ -175,14 +175,13 @@ addBK mp mp2 g nid n
                  rhs' <- g rhs >>* deAnd
                  return $ And $ map (\(x,y) -> x `mappend` y) $ product2 (lhs', rhs')
           | otherwise
-             = do mOp <- functionOperator fn
-                  ts <- mapM astTypeOf [lhs, rhs]
+             = do mOp <- builtInOperator fn
                   case mOp of
                     Nothing -> return mempty
                     Just op ->
-                      if A.nameName fn == occamDefaultOperator op ts
-                        then let noAndOr :: PassM a -> PassM (And (Or a))
-                                 noAndOr = liftM (noAnd . noOr) in case op of
+                      let noAndOr :: PassM a -> PassM (And (Or a))
+                          noAndOr = liftM (noAnd . noOr)
+                      in case op of
                           "=" -> noAndOr $ return $ Equal lhs rhs
                           "<=" -> noAndOr $ return $ LessThanOrEqual lhs rhs
                           ">=" -> noAndOr $ return $ LessThanOrEqual rhs lhs
@@ -196,7 +195,6 @@ addBK mp mp2 g nid n
                              return $ Or [LessThanOrEqual lhs_p1 rhs
                                          ,LessThanOrEqual rhs_p1 lhs]
                           _ -> return mempty
-                        else return mempty
           where
             bop n = A.Name emptyMeta $ occamDefaultOperator n [A.Bool, A.Bool]
         g (A.FunctionCall _ fn [rhs])

common/Types.hs

@@ -22,7 +22,7 @@ module Types
     specTypeOfName, typeOfSpec, typeOfSpec', abbrevModeOfName, underlyingType, underlyingTypeOf, stripArrayType, abbrevModeOfVariable, abbrevModeOfSpec
     , isRealType, isIntegerType, isNumericType, isCaseableType, isScalarType, isDataType, isCommunicableType, isSequenceType, isMobileType
     , resolveUserType, isSafeConversion, isPreciseConversion, isImplicitConversionRain
-    , isOperator, functionOperator, occamDefaultOperator, occamBuiltInOperatorFunctions, occamOperatorTranslateDefault
+    , isOperator, functionOperator, builtInOperator, occamDefaultOperator, occamBuiltInOperatorFunctions, occamOperatorTranslateDefault
     , returnTypesOfFunction
     , BytesInResult(..), bytesInType, countReplicator, countStructured, computeStructured
 
@@ -45,6 +45,7 @@ import qualified Data.Map as Map
 import Data.Maybe
 import Data.List
 import Data.Ord
+import qualified Data.Set as Set
 
 import qualified AST as A
 import CompState hiding (CSM) -- all these functions are read-only!
@@ -698,6 +699,18 @@ functionOperator n
       >>* A.ndOrigName
       >>* (\op -> if isOperator op then Just op else Nothing)
 
+-- Only gives back a Just result if it's a non-overridden operator
+builtInOperator :: (CSMR m, Die m) => A.Name -> m (Maybe String)
+builtInOperator n
+  = do mOp <- functionOperator n
+       return $ case mOp of
+         Nothing -> Nothing
+         Just op
+           | A.nameName n `Set.member` occamBuiltInOperatorFunctionsSet
+             -> Just op
+           | otherwise
+             -> Nothing
+
 isOperator :: String -> Bool
 isOperator op = any (== op) operatorNames
 
@@ -792,6 +805,9 @@ occamBuiltInOperatorFunctions
   = [occamDefaultOperator n ts
     | (n, _, ts) <- occamIntrinsicOperators]
 
+occamBuiltInOperatorFunctionsSet :: Set.Set String
+occamBuiltInOperatorFunctionsSet = Set.fromList occamBuiltInOperatorFunctions
+
 -- | Add one to an expression.
 addOne :: (CSMR m, Die m) => A.Expression -> m A.Expression
 addOne e = addExprs (makeConstant m 1) e

transformations/SimplifyExprs.hs

@@ -115,7 +115,7 @@ removeAfter = pass "Convert AFTER to MINUS"
     doFunctionCall :: (Meta -> A.Name -> [A.Expression] -> a)
       -> Meta -> A.Name -> [A.Expression] -> PassM a
     doFunctionCall f m n args
-        =  do mOp <- functionOperator n
+        =  do mOp <- builtInOperator n
               ts <- mapM astTypeOf args
               let op s = A.Name (A.nameMeta n) $ occamDefaultOperator s ts
               case mOp of
@@ -128,7 +128,7 @@ removeAfter = pass "Convert AFTER to MINUS"
                                  [A.FunctionCall m (op "MINUS") args
                                  , one]
                                ,oneTwoSeven]
-                  | n == op "AFTER" -- It hasn't been over-ridden
+                  | otherwise
                    -> let zero = A.Literal m (head ts) $ A.IntLiteral m "0"
                       in return $ f m (op ">") [A.FunctionCall m (op "MINUS") args, zero]
                 _ -> return $ f m n args