blob: 44f554ee47f82ff661a323a74d24735681243a2e (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
|
-- Test purpose:
-- Ensure that -Wno-compat disables a previously set -Wcompat
{-# OPTIONS_GHC -Wcompat #-}
{-# OPTIONS_GHC -Wno-compat #-}
module WCompatWarningsOnOff where
import qualified Data.Semigroup as Semi
monadFail :: Monad m => m a
monadFail = do
Just _ <- undefined
undefined
(<>) = undefined -- Semigroup warnings
-- -fwarn-noncanonical-monoid-instances
newtype S = S Int
instance Semi.Semigroup S where
(<>) = mappend
instance Semi.Monoid S where
S a `mappend` S b = S (a+b)
mempty = S 0
|
