f3d1bb0 · rowtype-yoga/purescript-native

examples/passing/TypeClasses.purs+5

compare with golang

unifiedsplit

@@ -40,3 +40,8 @@ test4 = ret 1

40

41test5 = Just 1 >>= \n -> ret (n + 1)

42

43+module TypeClasses2 where

44+

45+instance (TypeClasses.Show a) => TypeClasses.Show [a] where

46+ show [] = "[]"

47+ show (x:xs) = TypeClasses.show x ++ ", " ++ TypeClasses.show xs

src/Language/PureScript/Sugar/TypeClasses.hs+1−1

@@ -93,7 +93,7 @@ typeInstanceDictionaryDeclaration mn deps name ty decls = do

93typeInstanceDictionaryEntryDeclaration :: ModuleName -> [(Qualified ProperName, Type)] -> Qualified ProperName -> Type -> Declaration -> Desugar Declaration

94typeInstanceDictionaryEntryDeclaration mn deps name ty (ValueDeclaration ident [] _ val) = do

95 m <- get

96− let valTy = fromMaybe (error "Type class instance dictionary member is missing in typeInstanceDictionaryEntryDeclaration") $

96+ valTy <- lift $ maybe (Left $ "Type class " ++ show name ++ " is undefined. Type class names must be qualified.") Right $

97 do (arg, members) <- M.lookup (qualify mn name) m

98 ty' <- lookup (identToJs ident) members

99 return $ replaceTypeVars arg ty ty'

src/Language/PureScript/TypeChecker/Types.hs+3−2

@@ -192,7 +192,7 @@ entails :: ModuleName -> [TypeClassDictionaryInScope] -> (Qualified ProperName,

192entails moduleName context goal@(className, ty) = do

193 env <- getEnv

194 case go env goal of

195− [] -> throwError $ "No " ++ show className ++ " instance found for " ++ prettyPrintType ty

195+ [] -> throwError $ "No " ++ show className ++ " instance found for " ++ show context

196 (dict : _) -> return dict

197 where

198 go env (className', ty') =

@@ -213,7 +213,8 @@ typeHeadsAreEqual _ _ String String = Just []

213typeHeadsAreEqual _ _ Number Number = Just []

214typeHeadsAreEqual _ _ Boolean Boolean = Just []

215typeHeadsAreEqual _ _ (Skolem s1) (Skolem s2) | s1 == s2 = Just []

216−typeHeadsAreEqual m e (Array ty1) (Array ty2) = typeHeadsAreEqual m e ty1 ty2

216+typeHeadsAreEqual m e (Array (TypeVar v)) (Array ty) = Just [(v, ty)]

217+typeHeadsAreEqual m e (Array ty) (Array (TypeVar v)) = Just [(v, ty)]

217typeHeadsAreEqual m e (TypeConstructor c1) (TypeConstructor c2) | typeConstructorsAreEqual e m c1 c2 = Just []

218typeHeadsAreEqual m e (TypeConstructor c1) (TypeConstructor c2) | typeConstructorsAreEqual e m c1 c2 = Just []

218typeHeadsAreEqual m e (TypeApp h1 (TypeVar v)) (TypeApp h2 arg) = (:) (v, arg) <$> typeHeadsAreEqual m e h1 h2

219typeHeadsAreEqual m e (TypeApp h1 (TypeVar v)) (TypeApp h2 arg) = (:) (v, arg) <$> typeHeadsAreEqual m e h1 h2

219typeHeadsAreEqual m e t1@(TypeApp _ _) t2@(TypeApp _ (TypeVar _)) = typeHeadsAreEqual m e t2 t1

220typeHeadsAreEqual m e t1@(TypeApp _ _) t2@(TypeApp _ (TypeVar _)) = typeHeadsAreEqual m e t2 t1