Guards, use them

1 files changed, 8 insertions, 12 deletions

diff --git a/src/Compiler.hs b/src/Compiler.hs
index ce31299..fdf6930 100644
--- a/src/Compiler.hs
+++ b/src/Compiler.hs
@@ -48,14 +48,11 @@ typecheckCall args params
       -- resolve all args types
       targs <- fmap rights $ traverse compile args
       case sequence targs of
-        Just t ->
-          if length t /= length params
-            then -- there was an error in one argument
-              return $ Nothing
-            else
-              if all (\(a, b) -> a == b) $ zip t params -- compare types
-                then return $ Nothing -- all good!
-                else return $ Just ("type mismatch in function call\n     found: " ++ A.showList t ++ "\n  expected: " ++ A.showList params)
+        Just t
+          | length t /= length params -> return $ Nothing
+          | all (\(a, b) -> a == b) $ zip t params -> -- compare types
+              return $ Nothing -- all good!
+          | 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
@@ -70,10 +67,9 @@ typecheckVal :: A.Expr -> Maybe A.Type -> State CompState (Maybe String)
 typecheckVal value typ = do
   r <- compile value
   case r of
-    Right r ->
-      if r == typ
-        then return $ Nothing
-        else return $ Just $ "type mismatch\n     found: " ++ showMaybet r ++ "\n  expected: " ++ showMaybet typ
+    Right r
+      | r == typ -> return $ Nothing
+      | otherwise -> return $ Just $ "type mismatch\n     found: " ++ showMaybet r ++ "\n  expected: " ++ showMaybet typ
     Left _ -> return $ Nothing -- error resolving value
 
 -- | @typecheckReturn value fret@ resolves @value@ and compares it with @fret@,