✨

a2/a2-handout/src/APL/Check.hs

@@ -27,9 +27,9 @@ instance Monad CheckM where
         let CheckM y = f x'
          in y vars
 
-elem' :: VName -> [VName] -> Bool
-elem' _ [] = False
-elem' x (y : ys) = if x == y then True else elem' x ys
+inList :: VName -> [VName] -> Bool
+inList _ [] = False
+inList x (y : ys) = if x == y then True else inList x ys
 
 askVars :: CheckM Vars
 askVars = CheckM $ \vars -> Right vars
@@ -68,7 +68,7 @@ check (KvGet e1) = check e1
 check (KvPut e1 e2) = checkBinOp e1 e2
 check (Var v) = do
   vars <- askVars
-  if elem' v vars
+  if inList v vars
     then pure ()
     else CheckM $ \_vars -> Left $ "Variable not in scope: "++v
 check (Let var e1 e2) = do