ref: b4a7a0d4c04ad0fb96d0b279d35da2658d58a0e1
dir: /lib/Data/Functor/Classes.hs/
module Data.Functor.Classes (
-- * Liftings of Prelude classes
-- ** For unary constructors
Eq1(..), eq1,
Ord1(..), compare1,
Read1(..), readsPrec1, readPrec1,
liftReadListDefault, liftReadListPrecDefault,
Show1(..), showsPrec1,
-- ** For binary constructors
Eq2(..), eq2,
Ord2(..), compare2,
Read2(..), readsPrec2, readPrec2,
liftReadList2Default, liftReadListPrec2Default,
Show2(..), showsPrec2,
-- * Helper functions
readsData, readData,
readsUnaryWith, readUnaryWith,
readsBinaryWith, readBinaryWith,
showsUnaryWith,
showsBinaryWith,
) where
import Control.Applicative (Alternative((<|>)), Const(Const))
import Data.Functor.Identity (Identity(Identity))
import Data.Proxy (Proxy(Proxy))
import Data.List.NonEmpty (NonEmpty(..))
--import Data.Ord (Down(Down))
import Data.Complex (Complex((:+)))
import Data.Tuple (Solo (..))
import Text.Read
import Text.Read.Internal
import Text.Show (showListWith)
class Eq1 f where
liftEq :: (a -> b -> Bool) -> f a -> f b -> Bool
eq1 :: (Eq1 f, Eq a) => f a -> f a -> Bool
eq1 = liftEq (==)
class (Eq1 f) => Ord1 f where
liftCompare :: (a -> b -> Ordering) -> f a -> f b -> Ordering
compare1 :: (Ord1 f, Ord a) => f a -> f a -> Ordering
compare1 = liftCompare compare
class Read1 f where
liftReadsPrec :: (Int -> ReadS a) -> ReadS [a] -> Int -> ReadS (f a)
liftReadsPrec rp rl = readPrec_to_S $
liftReadPrec (readS_to_Prec rp) (readS_to_Prec (const rl))
liftReadList :: (Int -> ReadS a) -> ReadS [a] -> ReadS [f a]
liftReadList rp rl = readPrec_to_S
(list $ liftReadPrec (readS_to_Prec rp) (readS_to_Prec (const rl))) 0
liftReadPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec (f a)
liftReadPrec rp rl = readS_to_Prec $
liftReadsPrec (readPrec_to_S rp) (readPrec_to_S rl 0)
liftReadListPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec [f a]
liftReadListPrec rp rl = readS_to_Prec $ \_ ->
liftReadList (readPrec_to_S rp) (readPrec_to_S rl 0)
readsPrec1 :: (Read1 f, Read a) => Int -> ReadS (f a)
readsPrec1 = liftReadsPrec readsPrec readList
readPrec1 :: (Read1 f, Read a) => ReadPrec (f a)
readPrec1 = liftReadPrec readPrec readListPrec
liftReadListDefault :: Read1 f => (Int -> ReadS a) -> ReadS [a] -> ReadS [f a]
liftReadListDefault rp rl = readPrec_to_S
(liftReadListPrec (readS_to_Prec rp) (readS_to_Prec (const rl))) 0
liftReadListPrecDefault :: Read1 f => ReadPrec a -> ReadPrec [a]
-> ReadPrec [f a]
liftReadListPrecDefault rp rl = list (liftReadPrec rp rl)
class Show1 f where
liftShowsPrec :: (Int -> a -> ShowS) -> ([a] -> ShowS) ->
Int -> f a -> ShowS
liftShowList :: (Int -> a -> ShowS) -> ([a] -> ShowS) ->
[f a] -> ShowS
liftShowList sp sl = showListWith (liftShowsPrec sp sl 0)
showsPrec1 :: (Show1 f, Show a) => Int -> f a -> ShowS
showsPrec1 = liftShowsPrec showsPrec showList
class Eq2 f where
liftEq2 :: (a -> b -> Bool) -> (c -> d -> Bool) -> f a c -> f b d -> Bool
eq2 :: (Eq2 f, Eq a, Eq b) => f a b -> f a b -> Bool
eq2 = liftEq2 (==) (==)
class (Eq2 f) => Ord2 f where
liftCompare2 :: (a -> b -> Ordering) -> (c -> d -> Ordering) ->
f a c -> f b d -> Ordering
compare2 :: (Ord2 f, Ord a, Ord b) => f a b -> f a b -> Ordering
compare2 = liftCompare2 compare compare
class Read2 f where
liftReadsPrec2 :: (Int -> ReadS a) -> ReadS [a] ->
(Int -> ReadS b) -> ReadS [b] -> Int -> ReadS (f a b)
liftReadsPrec2 rp1 rl1 rp2 rl2 = readPrec_to_S $
liftReadPrec2 (readS_to_Prec rp1) (readS_to_Prec (const rl1))
(readS_to_Prec rp2) (readS_to_Prec (const rl2))
liftReadList2 :: (Int -> ReadS a) -> ReadS [a] ->
(Int -> ReadS b) -> ReadS [b] -> ReadS [f a b]
liftReadList2 rp1 rl1 rp2 rl2 = readPrec_to_S
(list $ liftReadPrec2 (readS_to_Prec rp1) (readS_to_Prec (const rl1))
(readS_to_Prec rp2) (readS_to_Prec (const rl2))) 0
liftReadPrec2 :: ReadPrec a -> ReadPrec [a] ->
ReadPrec b -> ReadPrec [b] -> ReadPrec (f a b)
liftReadPrec2 rp1 rl1 rp2 rl2 = readS_to_Prec $
liftReadsPrec2 (readPrec_to_S rp1) (readPrec_to_S rl1 0)
(readPrec_to_S rp2) (readPrec_to_S rl2 0)
liftReadListPrec2 :: ReadPrec a -> ReadPrec [a] ->
ReadPrec b -> ReadPrec [b] -> ReadPrec [f a b]
liftReadListPrec2 rp1 rl1 rp2 rl2 = readS_to_Prec $ \_ ->
liftReadList2 (readPrec_to_S rp1) (readPrec_to_S rl1 0)
(readPrec_to_S rp2) (readPrec_to_S rl2 0)
readsPrec2 :: (Read2 f, Read a, Read b) => Int -> ReadS (f a b)
readsPrec2 = liftReadsPrec2 readsPrec readList readsPrec readList
readPrec2 :: (Read2 f, Read a, Read b) => ReadPrec (f a b)
readPrec2 = liftReadPrec2 readPrec readListPrec readPrec readListPrec
liftReadList2Default :: Read2 f => (Int -> ReadS a) -> ReadS [a] ->
(Int -> ReadS b) -> ReadS [b] ->ReadS [f a b]
liftReadList2Default rp1 rl1 rp2 rl2 = readPrec_to_S
(liftReadListPrec2 (readS_to_Prec rp1) (readS_to_Prec (const rl1))
(readS_to_Prec rp2) (readS_to_Prec (const rl2))) 0
liftReadListPrec2Default :: Read2 f => ReadPrec a -> ReadPrec [a] ->
ReadPrec b -> ReadPrec [b] -> ReadPrec [f a b]
liftReadListPrec2Default rp1 rl1 rp2 rl2 = list (liftReadPrec2 rp1 rl1 rp2 rl2)
class Show2 f where
liftShowsPrec2 :: (Int -> a -> ShowS) -> ([a] -> ShowS) ->
(Int -> b -> ShowS) -> ([b] -> ShowS) -> Int -> f a b -> ShowS
liftShowList2 :: (Int -> a -> ShowS) -> ([a] -> ShowS) ->
(Int -> b -> ShowS) -> ([b] -> ShowS) -> [f a b] -> ShowS
liftShowList2 sp1 sl1 sp2 sl2 =
showListWith (liftShowsPrec2 sp1 sl1 sp2 sl2 0)
showsPrec2 :: (Show2 f, Show a, Show b) => Int -> f a b -> ShowS
showsPrec2 = liftShowsPrec2 showsPrec showList showsPrec showList
instance Eq1 Maybe where
liftEq _ Nothing Nothing = True
liftEq _ Nothing (Just _) = False
liftEq _ (Just _) Nothing = False
liftEq eq (Just x) (Just y) = eq x y
instance Ord1 Maybe where
liftCompare _ Nothing Nothing = EQ
liftCompare _ Nothing (Just _) = LT
liftCompare _ (Just _) Nothing = GT
liftCompare comp (Just x) (Just y) = comp x y
instance Read1 Maybe where
liftReadPrec rp _ =
parens (expectP (Ident "Nothing") *> pure Nothing)
<|>
readData (readUnaryWith rp "Just" Just)
liftReadListPrec = liftReadListPrecDefault
liftReadList = liftReadListDefault
instance Show1 Maybe where
liftShowsPrec _ _ _ Nothing = showString "Nothing"
liftShowsPrec sp _ d (Just x) = showsUnaryWith sp "Just" d x
instance Eq1 [] where
liftEq _ [] [] = True
liftEq _ [] (_:_) = False
liftEq _ (_:_) [] = False
liftEq eq (x:xs) (y:ys) = eq x y && liftEq eq xs ys
instance Ord1 [] where
liftCompare _ [] [] = EQ
liftCompare _ [] (_:_) = LT
liftCompare _ (_:_) [] = GT
liftCompare comp (x:xs) (y:ys) = comp x y `mappend` liftCompare comp xs ys
instance Read1 [] where
liftReadPrec _ rl = rl
liftReadListPrec = liftReadListPrecDefault
liftReadList = liftReadListDefault
instance Show1 [] where
liftShowsPrec _ sl _ = sl
instance Eq1 NonEmpty where
liftEq eq (a :| as) (b :| bs) = eq a b && liftEq eq as bs
instance Ord1 NonEmpty where
liftCompare cmp (a :| as) (b :| bs) = cmp a b `mappend` liftCompare cmp as bs
instance Read1 NonEmpty where
liftReadsPrec rdP rdL p s = readParen (p > 5) (\s' -> do
(a, s'') <- rdP 6 s'
(":|", s''') <- lex s''
(as, s'''') <- rdL s'''
return (a :| as, s'''')) s
instance Show1 NonEmpty where
liftShowsPrec shwP shwL p (a :| as) = showParen (p > 5) $
shwP 6 a . showString " :| " . shwL as
instance Eq2 (,) where
liftEq2 e1 e2 (x1, y1) (x2, y2) = e1 x1 x2 && e2 y1 y2
instance Ord2 (,) where
liftCompare2 comp1 comp2 (x1, y1) (x2, y2) =
comp1 x1 x2 `mappend` comp2 y1 y2
instance Read2 (,) where
liftReadPrec2 rp1 _ rp2 _ = parens $ paren $ do
x <- rp1
expectP (Punc ",")
y <- rp2
return (x,y)
liftReadListPrec2 = liftReadListPrec2Default
liftReadList2 = liftReadList2Default
instance Show2 (,) where
liftShowsPrec2 sp1 _ sp2 _ _ (x, y) =
showChar '(' . sp1 0 x . showChar ',' . sp2 0 y . showChar ')'
instance Eq1 Solo where
liftEq eq (MkSolo a) (MkSolo b) = a `eq` b
instance (Eq a) => Eq1 ((,) a) where
liftEq = liftEq2 (==)
instance Ord1 Solo where
liftCompare cmp (MkSolo a) (MkSolo b) = cmp a b
instance (Ord a) => Ord1 ((,) a) where
liftCompare = liftCompare2 compare
instance Read1 Solo where
liftReadPrec rp _ = readData (readUnaryWith rp "Solo" MkSolo)
liftReadListPrec = liftReadListPrecDefault
liftReadList = liftReadListDefault
instance (Read a) => Read1 ((,) a) where
liftReadPrec = liftReadPrec2 readPrec readListPrec
liftReadListPrec = liftReadListPrecDefault
liftReadList = liftReadListDefault
instance Show1 Solo where
liftShowsPrec sp _ d (MkSolo x) = showsUnaryWith sp "MkSolo" d x
instance (Show a) => Show1 ((,) a) where
liftShowsPrec = liftShowsPrec2 showsPrec showList
instance Eq a => Eq2 ((,,) a) where
liftEq2 e1 e2 (u1, x1, y1) (v1, x2, y2) =
u1 == v1 &&
e1 x1 x2 && e2 y1 y2
instance Ord a => Ord2 ((,,) a) where
liftCompare2 comp1 comp2 (u1, x1, y1) (v1, x2, y2) =
compare u1 v1 `mappend`
comp1 x1 x2 `mappend` comp2 y1 y2
instance Read a => Read2 ((,,) a) where
liftReadPrec2 rp1 _ rp2 _ = parens $ paren $ do
x1 <- readPrec
expectP (Punc ",")
y1 <- rp1
expectP (Punc ",")
y2 <- rp2
return (x1,y1,y2)
liftReadListPrec2 = liftReadListPrec2Default
liftReadList2 = liftReadList2Default
instance Show a => Show2 ((,,) a) where
liftShowsPrec2 sp1 _ sp2 _ _ (x1,y1,y2)
= showChar '(' . showsPrec 0 x1
. showChar ',' . sp1 0 y1
. showChar ',' . sp2 0 y2
. showChar ')'
instance (Eq a, Eq b) => Eq1 ((,,) a b) where
liftEq = liftEq2 (==)
instance (Ord a, Ord b) => Ord1 ((,,) a b) where
liftCompare = liftCompare2 compare
instance (Read a, Read b) => Read1 ((,,) a b) where
liftReadPrec = liftReadPrec2 readPrec readListPrec
liftReadListPrec = liftReadListPrecDefault
liftReadList = liftReadListDefault
instance (Show a, Show b) => Show1 ((,,) a b) where
liftShowsPrec = liftShowsPrec2 showsPrec showList
instance (Eq a, Eq b) => Eq2 ((,,,) a b) where
liftEq2 e1 e2 (u1, u2, x1, y1) (v1, v2, x2, y2) =
u1 == v1 &&
u2 == v2 &&
e1 x1 x2 && e2 y1 y2
instance (Ord a, Ord b) => Ord2 ((,,,) a b) where
liftCompare2 comp1 comp2 (u1, u2, x1, y1) (v1, v2, x2, y2) =
compare u1 v1 `mappend`
compare u2 v2 `mappend`
comp1 x1 x2 `mappend` comp2 y1 y2
instance (Read a, Read b) => Read2 ((,,,) a b) where
liftReadPrec2 rp1 _ rp2 _ = parens $ paren $ do
x1 <- readPrec
expectP (Punc ",")
x2 <- readPrec
expectP (Punc ",")
y1 <- rp1
expectP (Punc ",")
y2 <- rp2
return (x1,x2,y1,y2)
liftReadListPrec2 = liftReadListPrec2Default
liftReadList2 = liftReadList2Default
instance (Show a, Show b) => Show2 ((,,,) a b) where
liftShowsPrec2 sp1 _ sp2 _ _ (x1,x2,y1,y2)
= showChar '(' . showsPrec 0 x1
. showChar ',' . showsPrec 0 x2
. showChar ',' . sp1 0 y1
. showChar ',' . sp2 0 y2
. showChar ')'
instance (Eq a, Eq b, Eq c) => Eq1 ((,,,) a b c) where
liftEq = liftEq2 (==)
instance (Ord a, Ord b, Ord c) => Ord1 ((,,,) a b c) where
liftCompare = liftCompare2 compare
instance (Read a, Read b, Read c) => Read1 ((,,,) a b c) where
liftReadPrec = liftReadPrec2 readPrec readListPrec
liftReadListPrec = liftReadListPrecDefault
liftReadList = liftReadListDefault
instance (Show a, Show b, Show c) => Show1 ((,,,) a b c) where
liftShowsPrec = liftShowsPrec2 showsPrec showList
{-
instance (Generic1 f, Eq1 (Rep1 f)) => Eq1 (Generically1 f) where
liftEq :: (a1 -> a2 -> Bool) -> (Generically1 f a1 -> Generically1 f a2 -> Bool)
liftEq (===) (Generically1 as1) (Generically1 as2) = liftEq (===) (from1 as1) (from1 as2)
instance (Generic1 f, Ord1 (Rep1 f)) => Ord1 (Generically1 f) where
liftCompare :: (a1 -> a2 -> Ordering) -> (Generically1 f a1 -> Generically1 f a2 -> Ordering)
liftCompare cmp (Generically1 as1) (Generically1 as2) = liftCompare cmp (from1 as1) (from1 as2)
-}
instance Eq2 Either where
liftEq2 e1 _ (Left x) (Left y) = e1 x y
liftEq2 _ _ (Left _) (Right _) = False
liftEq2 _ _ (Right _) (Left _) = False
liftEq2 _ e2 (Right x) (Right y) = e2 x y
instance Ord2 Either where
liftCompare2 comp1 _ (Left x) (Left y) = comp1 x y
liftCompare2 _ _ (Left _) (Right _) = LT
liftCompare2 _ _ (Right _) (Left _) = GT
liftCompare2 _ comp2 (Right x) (Right y) = comp2 x y
instance Read2 Either where
liftReadPrec2 rp1 _ rp2 _ = readData $
readUnaryWith rp1 "Left" Left <|>
readUnaryWith rp2 "Right" Right
liftReadListPrec2 = liftReadListPrec2Default
liftReadList2 = liftReadList2Default
instance Show2 Either where
liftShowsPrec2 sp1 _ _ _ d (Left x) = showsUnaryWith sp1 "Left" d x
liftShowsPrec2 _ _ sp2 _ d (Right x) = showsUnaryWith sp2 "Right" d x
instance (Eq a) => Eq1 (Either a) where
liftEq = liftEq2 (==)
instance (Ord a) => Ord1 (Either a) where
liftCompare = liftCompare2 compare
instance (Read a) => Read1 (Either a) where
liftReadPrec = liftReadPrec2 readPrec readListPrec
liftReadListPrec = liftReadListPrecDefault
liftReadList = liftReadListDefault
instance (Show a) => Show1 (Either a) where
liftShowsPrec = liftShowsPrec2 showsPrec showList
instance Eq1 Identity where
liftEq eq (Identity x) (Identity y) = eq x y
instance Ord1 Identity where
liftCompare comp (Identity x) (Identity y) = comp x y
{-
instance Read1 Identity where
liftReadPrec rp _ = readData $
readUnaryWith rp "Identity" Identity
liftReadListPrec = liftReadListPrecDefault
liftReadList = liftReadListDefault
-}
instance Show1 Identity where
liftShowsPrec sp _ d (Identity x) = showsUnaryWith sp "Identity" d x
instance Eq2 Const where
liftEq2 eq _ (Const x) (Const y) = eq x y
instance Ord2 Const where
liftCompare2 comp _ (Const x) (Const y) = comp x y
{-
instance Read2 Const where
liftReadPrec2 rp _ _ _ = readData $
readUnaryWith rp "Const" Const
liftReadListPrec2 = liftReadListPrec2Default
liftReadList2 = liftReadList2Default
-}
instance Show2 Const where
liftShowsPrec2 sp _ _ _ d (Const x) = showsUnaryWith sp "Const" d x
instance (Eq a) => Eq1 (Const a) where
liftEq = liftEq2 (==)
instance (Ord a) => Ord1 (Const a) where
liftCompare = liftCompare2 compare
{-
instance (Read a) => Read1 (Const a) where
liftReadPrec = liftReadPrec2 readPrec readListPrec
liftReadListPrec = liftReadListPrecDefault
liftReadList = liftReadListDefault
-}
instance (Show a) => Show1 (Const a) where
liftShowsPrec = liftShowsPrec2 showsPrec showList
instance Eq1 Proxy where
liftEq _ _ _ = True
instance Ord1 Proxy where
liftCompare _ _ _ = EQ
instance Show1 Proxy where
liftShowsPrec _ _ _ _ = showString "Proxy"
{-
instance Read1 Proxy where
liftReadPrec _ _ = parens (expectP (Ident "Proxy") *> pure Proxy)
liftReadListPrec = liftReadListPrecDefault
liftReadList = liftReadListDefault
-}
{-
instance Eq1 Down where
liftEq eq (Down x) (Down y) = eq x y
instance Ord1 Down where
liftCompare comp (Down x) (Down y) = case comp x y of
LT -> GT
EQ -> EQ
GT -> LT
{-
instance Read1 Down where
liftReadsPrec rp _ = readsData $
readsUnaryWith rp "Down" Down
-}
instance Show1 Down where
liftShowsPrec sp _ d (Down x) = showsUnaryWith sp "Down" d x
-}
instance Eq1 Complex where
liftEq eq (x :+ y) (u :+ v) = eq x u && eq y v
{-
instance Read1 Complex where
liftReadPrec rp _ = parens $ prec complexPrec $ do
x <- step rp
expectP (Symbol ":+")
y <- step rp
return (x :+ y)
where
complexPrec = 6
liftReadListPrec = liftReadListPrecDefault
liftReadList = liftReadListDefault
-}
instance Show1 Complex where
liftShowsPrec sp _ d (x :+ y) = showParen (d > complexPrec) $
sp (complexPrec+1) x . showString " :+ " . sp (complexPrec+1) y
where
complexPrec = 6
readsData :: (String -> ReadS a) -> Int -> ReadS a
readsData reader d =
readParen (d > 10) $ \ r -> [res | (kw,s) <- lex r, res <- reader kw s]
readData :: ReadPrec a -> ReadPrec a
readData reader = parens $ prec 10 reader
readsUnaryWith :: (Int -> ReadS a) -> String -> (a -> t) -> String -> ReadS t
readsUnaryWith rp name cons kw s =
[(cons x,t) | kw == name, (x,t) <- rp 11 s]
readUnaryWith :: ReadPrec a -> String -> (a -> t) -> ReadPrec t
readUnaryWith rp name cons = do
expectP $ Ident name
x <- step rp
return $ cons x
readsBinaryWith :: (Int -> ReadS a) -> (Int -> ReadS b) ->
String -> (a -> b -> t) -> String -> ReadS t
readsBinaryWith rp1 rp2 name cons kw s =
[(cons x y,u) | kw == name, (x,t) <- rp1 11 s, (y,u) <- rp2 11 t]
readBinaryWith :: ReadPrec a -> ReadPrec b ->
String -> (a -> b -> t) -> ReadPrec t
readBinaryWith rp1 rp2 name cons = do
expectP $ Ident name
x <- step rp1
y <- step rp2
return $ cons x y
showsUnaryWith :: (Int -> a -> ShowS) -> String -> Int -> a -> ShowS
showsUnaryWith sp name d x = showParen (d > 10) $
showString name . showChar ' ' . sp 11 x
showsBinaryWith :: (Int -> a -> ShowS) -> (Int -> b -> ShowS) ->
String -> Int -> a -> b -> ShowS
showsBinaryWith sp1 sp2 name d x y = showParen (d > 10) $
showString name . showChar ' ' . sp1 11 x . showChar ' ' . sp2 11 y