Use pure for pure values

1 files changed, 7 insertions, 7 deletions

diff --git a/src/Compiler.hs b/src/Compiler.hs
index fdf6930..0511644 100644
--- a/src/Compiler.hs
+++ b/src/Compiler.hs
@@ -36,14 +36,14 @@ addError :: Error -> State CompState CompResult
 addError e = do
   (ev, errs) <- get
   put (ev, e : errs)
-  return $ Right Nothing
+  pure $ Right Nothing
 
 -- | @typecheckCall args params@ resolves @args@ and compares it with @params@,
 -- returning a string describing an error or Nothing in case of type match.
 typecheckCall :: [A.Expr] -> [A.Type] -> State CompState (Maybe String)
 typecheckCall args params
   | length args /= length params = return $ Just "invalid number of arguments in function call"
-  | length params == 0 = return $ Nothing
+  | length params == 0 = pure Nothing
   | otherwise = do
       -- resolve all args types
       targs <- fmap rights $ traverse compile args
@@ -55,7 +55,7 @@ typecheckCall args params
           | otherwise -> return $ Just ("type mismatch in function call\n     found: " ++ A.showList t ++ "\n  expected: " ++ A.showList params)
         Nothing ->
           -- there was an error in on argument
-          return $ Nothing
+          pure Nothing
 
 showMaybet :: Maybe A.Type -> String
 showMaybet Nothing = "()"
@@ -68,9 +68,9 @@ typecheckVal value typ = do
   r <- compile value
   case r of
     Right r
-      | r == typ -> return $ Nothing
+      | r == typ -> pure Nothing
       | otherwise -> return $ Just $ "type mismatch\n     found: " ++ showMaybet r ++ "\n  expected: " ++ showMaybet typ
-    Left _ -> return $ Nothing -- error resolving value
+    Left _ -> pure Nothing -- error resolving value
 
 -- | @typecheckReturn value fret@ resolves @value@ and compares it with @fret@,
 -- returning a string decribing an error or Nothing in case of a type match.
@@ -145,7 +145,7 @@ compile x = do
             Just err -> addError $ Error TypeError err pos
             Nothing -> return $ Right rtyp
         Right _ -> addError $ Error NonCallable "non callable value in function call" pos
-        _ -> return $ Right Nothing
+        _ -> pure $ Right Nothing
     (A.Var ident typ val priv pos) -> do
       (ev, errs) <- get
       (ev, errs) <- return $ foldlEither addSymUniq (ev, errs) [(ident, typ, priv, pos)]
@@ -181,5 +181,5 @@ compileAll (x : xs) = do
 compileAll [] = do
   (_, errs) <- get
   case errs of
-    [] -> return $ Right Nothing
+    [] -> pure $ Right Nothing
     _ -> return $ Left errs