blob: 76f387d636c553beef9d311c474dee83e2f5ed5e (
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
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
|
{-# LANGUAGE MultiParamTypeClasses #-}
{-# LANGUAGE TypeSynonymInstances #-}
{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE TypeOperators #-}
{-# LANGUAGE DefaultSignatures #-}
{-# LANGUAGE IncoherentInstances #-} -- necessary, unfortunately
module GUniplate where
import GHC.Generics
--------------------------------------------------------------------------------
-- Generic Uniplate
--------------------------------------------------------------------------------
class Uniplate' f b where
children' :: f a -> [b]
instance Uniplate' U1 a where
children' U1 = []
instance Uniplate' (K1 i a) a where
children' (K1 a) = [a]
instance Uniplate' (K1 i a) b where
children' (K1 _) = []
instance (Uniplate' f b) => Uniplate' (M1 i c f) b where
children' (M1 a) = children' a
instance (Uniplate' f b, Uniplate' g b) => Uniplate' (f :+: g) b where
children' (L1 a) = children' a
children' (R1 a) = children' a
instance (Uniplate' f b, Uniplate' g b) => Uniplate' (f :*: g) b where
children' (a :*: b) = children' a ++ children' b
class Uniplate a where
children :: a -> [a]
default children :: (Generic a, Uniplate' (Rep a) a) => a -> [a]
children = children' . from
-- Base types instances
instance Uniplate Char where children _ = []
instance Uniplate Int where children _ = []
instance Uniplate Float where children _ = []
instance Uniplate [a] where
children [] = []
children (_:t) = [t]
|
