blob: 68d0dd4714197960e24ac487c3c004675fcd31e3 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
|
{-# OPTIONS_GHC -fno-warn-redundant-constraints #-}
{-# LANGUAGE FunctionalDependencies, FlexibleContexts #-}
class C a where
class D a where
dop :: a -> a
instance C a => D [a] where
dop = undefined
class J a b | a -> b
where j :: a -> b -> ()
instance J Bool Int where
j = undefined
foo :: D [Int] => ()
foo = j True (head (dop [undefined]))
main = return ()
|