Copyright	[2018..2020] The Accelerate Team
License	BSD3
Maintainer	Trevor L. McDonell <trevor.mcdonell@gmail.com>
Stability	experimental
Portability	non-portable (GHC extensions)
Safe Haskell	Safe-Inferred
Language	Haskell2010

Data.Array.Accelerate.Data.Maybe

Contents

Orphan instances

Description

Since: 1.2.0.0

Synopsis

data Maybe a
- = Nothing
- | Just a
pattern Nothing_ :: forall a. (HasCallStack, Elt a) => Exp (Maybe a)
pattern Just_ :: forall a. (HasCallStack, Elt a) => Exp a -> Exp (Maybe a)
maybe :: (Elt a, Elt b) => Exp b -> (Exp a -> Exp b) -> Exp (Maybe a) -> Exp b
isJust :: Elt a => Exp (Maybe a) -> Exp Bool
isNothing :: Elt a => Exp (Maybe a) -> Exp Bool
fromMaybe :: Elt a => Exp a -> Exp (Maybe a) -> Exp a
fromJust :: Elt a => Exp (Maybe a) -> Exp a
justs :: (Shape sh, Slice sh, Elt a) => Acc (Array (sh :. Int) (Maybe a)) -> Acc (Vector a, Array sh Int)

Documentation

data Maybe a #

The Maybe type encapsulates an optional value. A value of type Maybe a either contains a value of type a (represented as Just a), or it is empty (represented as Nothing). Using Maybe is a good way to deal with errors or exceptional cases without resorting to drastic measures such as error.

The Maybe type is also a monad. It is a simple kind of error monad, where all errors are represented by Nothing. A richer error monad can be built using the Either type.

Constructors

Nothing
Just a

Instances

Instances details

Monad Maybe Source #
Instance details Defined in Data.Array.Accelerate.Data.Maybe Methods (>>=) :: (Elt a, Elt b, Elt (Maybe a), Elt (Maybe b)) => Exp (Maybe a) -> (Exp a -> Exp (Maybe b)) -> Exp (Maybe b) Source # return :: (Elt a, Elt (Maybe a)) => Exp a -> Exp (Maybe a) Source #
Functor Maybe Source #
Instance details Defined in Data.Array.Accelerate.Data.Maybe Methods fmap :: (Elt a, Elt b, Elt (Maybe a), Elt (Maybe b)) => (Exp a -> Exp b) -> Exp (Maybe a) -> Exp (Maybe b) Source # (<$) :: (Elt a, Elt b, Elt (Maybe a), Elt (Maybe b)) => Exp a -> Exp (Maybe b) -> Exp (Maybe a) Source #
MonadFail Maybe	Since: base-4.9.0.0
Instance details Defined in Control.Monad.Fail Methods fail :: String -> Maybe a #
MonadFix Maybe	Since: base-2.1
Instance details Defined in Control.Monad.Fix Methods mfix :: (a -> Maybe a) -> Maybe a #
Foldable Maybe	Since: base-2.1
Instance details Defined in Data.Foldable Methods fold :: Monoid m => Maybe m -> m # foldMap :: Monoid m => (a -> m) -> Maybe a -> m # foldMap' :: Monoid m => (a -> m) -> Maybe a -> m # foldr :: (a -> b -> b) -> b -> Maybe a -> b # foldr' :: (a -> b -> b) -> b -> Maybe a -> b # foldl :: (b -> a -> b) -> b -> Maybe a -> b # foldl' :: (b -> a -> b) -> b -> Maybe a -> b # foldr1 :: (a -> a -> a) -> Maybe a -> a # foldl1 :: (a -> a -> a) -> Maybe a -> a # toList :: Maybe a -> [a] # null :: Maybe a -> Bool # length :: Maybe a -> Int # elem :: Eq a => a -> Maybe a -> Bool # maximum :: Ord a => Maybe a -> a # minimum :: Ord a => Maybe a -> a # sum :: Num a => Maybe a -> a # product :: Num a => Maybe a -> a #
Eq1 Maybe	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Classes Methods liftEq :: (a -> b -> Bool) -> Maybe a -> Maybe b -> Bool #
Ord1 Maybe	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Classes Methods liftCompare :: (a -> b -> Ordering) -> Maybe a -> Maybe b -> Ordering #
Read1 Maybe	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Classes Methods liftReadsPrec :: (Int -> ReadS a) -> ReadS [a] -> Int -> ReadS (Maybe a) # liftReadList :: (Int -> ReadS a) -> ReadS [a] -> ReadS [Maybe a] # liftReadPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec (Maybe a) # liftReadListPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec [Maybe a] #
Show1 Maybe	Since: base-4.9.0.0
Instance details Defined in Data.Functor.Classes Methods liftShowsPrec :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> Int -> Maybe a -> ShowS # liftShowList :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> [Maybe a] -> ShowS #
Traversable Maybe	Since: base-2.1
Instance details Defined in Data.Traversable Methods traverse :: Applicative f => (a -> f b) -> Maybe a -> f (Maybe b) # sequenceA :: Applicative f => Maybe (f a) -> f (Maybe a) # mapM :: Monad m => (a -> m b) -> Maybe a -> m (Maybe b) # sequence :: Monad m => Maybe (m a) -> m (Maybe a) #
Alternative Maybe	Since: base-2.1
Instance details Defined in GHC.Base Methods empty :: Maybe a # (<\|>) :: Maybe a -> Maybe a -> Maybe a # some :: Maybe a -> Maybe [a] # many :: Maybe a -> Maybe [a] #
Applicative Maybe	Since: base-2.1
Instance details Defined in GHC.Base Methods pure :: a -> Maybe a # (<>) :: Maybe (a -> b) -> Maybe a -> Maybe b # liftA2 :: (a -> b -> c) -> Maybe a -> Maybe b -> Maybe c # (>) :: Maybe a -> Maybe b -> Maybe b # (<*) :: Maybe a -> Maybe b -> Maybe a #
Functor Maybe	Since: base-2.1
Instance details Defined in GHC.Base Methods fmap :: (a -> b) -> Maybe a -> Maybe b # (<$) :: a -> Maybe b -> Maybe a #
Monad Maybe	Since: base-2.1
Instance details Defined in GHC.Base Methods (>>=) :: Maybe a -> (a -> Maybe b) -> Maybe b # (>>) :: Maybe a -> Maybe b -> Maybe b # return :: a -> Maybe a #
MonadPlus Maybe	Since: base-2.1
Instance details Defined in GHC.Base Methods mzero :: Maybe a # mplus :: Maybe a -> Maybe a -> Maybe a #
NFData1 Maybe	Since: deepseq-1.4.3.0
Instance details Defined in Control.DeepSeq Methods liftRnf :: (a -> ()) -> Maybe a -> () #
MonadThrow Maybe
Instance details Defined in Control.Monad.Catch Methods throwM :: Exception e => e -> Maybe a #
Hashable1 Maybe
Instance details Defined in Data.Hashable.Class Methods liftHashWithSalt :: (Int -> a -> Int) -> Int -> Maybe a -> Int Source #
Generic1 Maybe
Instance details Defined in GHC.Generics Associated Types type Rep1 Maybe :: k -> Type # Methods from1 :: forall (a :: k). Maybe a -> Rep1 Maybe a # to1 :: forall (a :: k). Rep1 Maybe a -> Maybe a #
MonadBaseControl Maybe Maybe
Instance details Defined in Control.Monad.Trans.Control Associated Types type StM Maybe a Source # Methods liftBaseWith :: (RunInBase Maybe Maybe -> Maybe a) -> Maybe a Source # restoreM :: StM Maybe a -> Maybe a Source #
(Lift Exp a, Elt (Plain a)) => Lift Exp (Maybe a) Source #
Instance details Defined in Data.Array.Accelerate.Data.Maybe Associated Types type Plain (Maybe a) Source # Methods lift :: Maybe a -> Exp (Plain (Maybe a)) Source #
Lift a => Lift (Maybe a :: Type)
Instance details Defined in Language.Haskell.TH.Syntax Methods lift :: Quote m => Maybe a -> m Exp # liftTyped :: forall (m :: Type -> Type). Quote m => Maybe a -> Code m (Maybe a) #
Eq a => Eq (Maybe a) Source #
Instance details Defined in Data.Array.Accelerate.Data.Maybe Methods (==) :: Exp (Maybe a) -> Exp (Maybe a) -> Exp Bool Source # (/=) :: Exp (Maybe a) -> Exp (Maybe a) -> Exp Bool Source #
Ord a => Ord (Maybe a) Source #
Instance details Defined in Data.Array.Accelerate.Data.Maybe Methods (<) :: Exp (Maybe a) -> Exp (Maybe a) -> Exp Bool Source # (>) :: Exp (Maybe a) -> Exp (Maybe a) -> Exp Bool Source # (<=) :: Exp (Maybe a) -> Exp (Maybe a) -> Exp Bool Source # (>=) :: Exp (Maybe a) -> Exp (Maybe a) -> Exp Bool Source # min :: Exp (Maybe a) -> Exp (Maybe a) -> Exp (Maybe a) Source # max :: Exp (Maybe a) -> Exp (Maybe a) -> Exp (Maybe a) Source # compare :: Exp (Maybe a) -> Exp (Maybe a) -> Exp Ordering Source #
Elt a => Elt (Maybe a) Source #
Instance details Defined in Data.Array.Accelerate.Sugar.Elt Associated Types type EltR (Maybe a) Methods eltR :: TypeR (EltR (Maybe a)) tagsR :: [TagR (EltR (Maybe a))] fromElt :: Maybe a -> EltR (Maybe a) toElt :: EltR (Maybe a) -> Maybe a
Data a => Data (Maybe a)	Since: base-4.0.0.0
Instance details Defined in Data.Data Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Maybe a -> c (Maybe a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Maybe a) # toConstr :: Maybe a -> Constr # dataTypeOf :: Maybe a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Maybe a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Maybe a)) # gmapT :: (forall b. Data b => b -> b) -> Maybe a -> Maybe a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Maybe a -> r # gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Maybe a -> r # gmapQ :: (forall d. Data d => d -> u) -> Maybe a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Maybe a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Maybe a -> m (Maybe a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Maybe a -> m (Maybe a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Maybe a -> m (Maybe a) #
(Monoid (Exp a), Elt a) => Monoid (Exp (Maybe a)) Source #
Instance details Defined in Data.Array.Accelerate.Data.Maybe Methods mempty :: Exp (Maybe a) # mappend :: Exp (Maybe a) -> Exp (Maybe a) -> Exp (Maybe a) # mconcat :: [Exp (Maybe a)] -> Exp (Maybe a) #
Semigroup a => Monoid (Maybe a)	Lift a semigroup into `Maybe` forming a `Monoid` according to http://en.wikipedia.org/wiki/Monoid: "Any semigroup `S` may be turned into a monoid simply by adjoining an element `e` not in `S` and defining `ee = e` and `es = s = se` for all `s ∈ S`." Since 4.11.0: constraint on inner `a` value generalised from `Monoid` to `Semigroup`. Since: base-2.1*
Instance details Defined in GHC.Base Methods mempty :: Maybe a # mappend :: Maybe a -> Maybe a -> Maybe a # mconcat :: [Maybe a] -> Maybe a #
(Semigroup (Exp a), Elt a) => Semigroup (Exp (Maybe a)) Source #
Instance details Defined in Data.Array.Accelerate.Data.Maybe Methods (<>) :: Exp (Maybe a) -> Exp (Maybe a) -> Exp (Maybe a) # sconcat :: NonEmpty (Exp (Maybe a)) -> Exp (Maybe a) # stimes :: Integral b => b -> Exp (Maybe a) -> Exp (Maybe a) #
Semigroup a => Semigroup (Maybe a)	Since: base-4.9.0.0
Instance details Defined in GHC.Base Methods (<>) :: Maybe a -> Maybe a -> Maybe a # sconcat :: NonEmpty (Maybe a) -> Maybe a # stimes :: Integral b => b -> Maybe a -> Maybe a #
Generic (Maybe a)
Instance details Defined in GHC.Generics Associated Types type Rep (Maybe a) :: Type -> Type # Methods from :: Maybe a -> Rep (Maybe a) x # to :: Rep (Maybe a) x -> Maybe a #
SingKind a => SingKind (Maybe a)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Associated Types type DemoteRep (Maybe a) Methods fromSing :: forall (a0 :: Maybe a). Sing a0 -> DemoteRep (Maybe a)
Read a => Read (Maybe a)	Since: base-2.1
Instance details Defined in GHC.Read Methods readsPrec :: Int -> ReadS (Maybe a) # readList :: ReadS [Maybe a] # readPrec :: ReadPrec (Maybe a) # readListPrec :: ReadPrec [Maybe a] #
Show a => Show (Maybe a)	Since: base-2.1
Instance details Defined in GHC.Show Methods showsPrec :: Int -> Maybe a -> ShowS # show :: Maybe a -> String # showList :: [Maybe a] -> ShowS #
NFData a => NFData (Maybe a)
Instance details Defined in Control.DeepSeq Methods rnf :: Maybe a -> () #
Buildable a => Buildable (Maybe a)
Instance details Defined in Formatting.Buildable Methods build :: Maybe a -> Builder Source #
Eq a => Eq (Maybe a)	Since: base-2.1
Instance details Defined in GHC.Maybe Methods (==) :: Maybe a -> Maybe a -> Bool # (/=) :: Maybe a -> Maybe a -> Bool #
Ord a => Ord (Maybe a)	Since: base-2.1
Instance details Defined in GHC.Maybe Methods compare :: Maybe a -> Maybe a -> Ordering # (<) :: Maybe a -> Maybe a -> Bool # (<=) :: Maybe a -> Maybe a -> Bool # (>) :: Maybe a -> Maybe a -> Bool # (>=) :: Maybe a -> Maybe a -> Bool # max :: Maybe a -> Maybe a -> Maybe a # min :: Maybe a -> Maybe a -> Maybe a #
Hashable a => Hashable (Maybe a)
Instance details Defined in Data.Hashable.Class Methods hashWithSalt :: Int -> Maybe a -> Int Source # hash :: Maybe a -> Int Source #
Pretty a => Pretty (Maybe a)	Ignore `Nothing`s, print `Just` contents. `>>>` `pretty (Just True)`True `>>>` `braces (pretty (Nothing :: Maybe Bool))`{} `>>>` `pretty [Just 1, Nothing, Just 3, Nothing]`[1, 3]
Instance details Defined in Prettyprinter.Internal Methods pretty :: Maybe a -> Doc ann Source # prettyList :: [Maybe a] -> Doc ann Source #
Pretty a => Pretty (Maybe a)
Instance details Defined in Text.PrettyPrint.Annotated.WL Methods pretty :: Maybe a -> Doc b Source # prettyList :: [Maybe a] -> Doc b Source #
SingI ('Nothing :: Maybe a)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods sing :: Sing 'Nothing
Each (Maybe a) (Maybe b) a b
Instance details Defined in Lens.Micro.Internal Methods each :: Traversal (Maybe a) (Maybe b) a b Source #
SingI a2 => SingI ('Just a2 :: Maybe a1)	Since: base-4.9.0.0
Instance details Defined in GHC.Generics Methods sing :: Sing ('Just a2)
type Rep1 Maybe	Since: base-4.6.0.0
Instance details Defined in GHC.Generics type Rep1 Maybe = D1 ('MetaData "Maybe" "GHC.Maybe" "base" 'False) (C1 ('MetaCons "Nothing" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "Just" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) Par1))
type StM Maybe a
Instance details Defined in Control.Monad.Trans.Control type StM Maybe a = a
type Plain (Maybe a) Source #
Instance details Defined in Data.Array.Accelerate.Data.Maybe type Plain (Maybe a) = Maybe (Plain a)
type DemoteRep (Maybe a)
Instance details Defined in GHC.Generics type DemoteRep (Maybe a) = Maybe (DemoteRep a)
type Rep (Maybe a)	Since: base-4.6.0.0
Instance details Defined in GHC.Generics type Rep (Maybe a) = D1 ('MetaData "Maybe" "GHC.Maybe" "base" 'False) (C1 ('MetaCons "Nothing" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "Just" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 a)))
data Sing (b :: Maybe a)
Instance details Defined in GHC.Generics data Sing (b :: Maybe a) where SNothing :: forall {a}. Sing ('Nothing :: Maybe a) SJust :: forall {a} (a1 :: a). Sing a1 -> Sing ('Just a1)

pattern Nothing_ :: forall a. (HasCallStack, Elt a) => Exp (Maybe a) Source #

pattern Just_ :: forall a. (HasCallStack, Elt a) => Exp a -> Exp (Maybe a) Source #

maybe :: (Elt a, Elt b) => Exp b -> (Exp a -> Exp b) -> Exp (Maybe a) -> Exp b Source #

The maybe function takes a default value, a function, and a Maybe value. If the Maybe value is nothing, the default value is returned; otherwise, it applies the function to the value inside the Just and returns the result

isJust :: Elt a => Exp (Maybe a) -> Exp Bool Source #

Returns True if the argument is of the form Just _

isNothing :: Elt a => Exp (Maybe a) -> Exp Bool Source #

Returns True if the argument is Nothing

fromMaybe :: Elt a => Exp a -> Exp (Maybe a) -> Exp a Source #

The fromMaybe function takes a default value and a Maybe value. If the Maybe is Nothing, the default value is returned; otherwise, it returns the value contained in the Maybe.

fromJust :: Elt a => Exp (Maybe a) -> Exp a Source #

The fromJust function extracts the element out of the Just constructor. If the argument was actually Nothing, you will get an undefined value instead.

justs :: (Shape sh, Slice sh, Elt a) => Acc (Array (sh :. Int) (Maybe a)) -> Acc (Vector a, Array sh Int) Source #

Extract from an array all of the Just values, together with a segment descriptor indicating how many elements along each dimension were returned.

Orphan instances

Monad Maybe Source #
Instance details Methods (>>=) :: (Elt a, Elt b, Elt (Maybe a), Elt (Maybe b)) => Exp (Maybe a) -> (Exp a -> Exp (Maybe b)) -> Exp (Maybe b) Source # return :: (Elt a, Elt (Maybe a)) => Exp a -> Exp (Maybe a) Source #
Functor Maybe Source #
Instance details Methods fmap :: (Elt a, Elt b, Elt (Maybe a), Elt (Maybe b)) => (Exp a -> Exp b) -> Exp (Maybe a) -> Exp (Maybe b) Source # (<$) :: (Elt a, Elt b, Elt (Maybe a), Elt (Maybe b)) => Exp a -> Exp (Maybe b) -> Exp (Maybe a) Source #
(Lift Exp a, Elt (Plain a)) => Lift Exp (Maybe a) Source #
Instance details Associated Types type Plain (Maybe a) Source # Methods lift :: Maybe a -> Exp (Plain (Maybe a)) Source #
Eq a => Eq (Maybe a) Source #
Instance details Methods (==) :: Exp (Maybe a) -> Exp (Maybe a) -> Exp Bool Source # (/=) :: Exp (Maybe a) -> Exp (Maybe a) -> Exp Bool Source #
Ord a => Ord (Maybe a) Source #
Instance details Methods (<) :: Exp (Maybe a) -> Exp (Maybe a) -> Exp Bool Source # (>) :: Exp (Maybe a) -> Exp (Maybe a) -> Exp Bool Source # (<=) :: Exp (Maybe a) -> Exp (Maybe a) -> Exp Bool Source # (>=) :: Exp (Maybe a) -> Exp (Maybe a) -> Exp Bool Source # min :: Exp (Maybe a) -> Exp (Maybe a) -> Exp (Maybe a) Source # max :: Exp (Maybe a) -> Exp (Maybe a) -> Exp (Maybe a) Source # compare :: Exp (Maybe a) -> Exp (Maybe a) -> Exp Ordering Source #
(Monoid (Exp a), Elt a) => Monoid (Exp (Maybe a)) Source #
Instance details Methods mempty :: Exp (Maybe a) # mappend :: Exp (Maybe a) -> Exp (Maybe a) -> Exp (Maybe a) # mconcat :: [Exp (Maybe a)] -> Exp (Maybe a) #
(Semigroup (Exp a), Elt a) => Semigroup (Exp (Maybe a)) Source #
Instance details Methods (<>) :: Exp (Maybe a) -> Exp (Maybe a) -> Exp (Maybe a) # sconcat :: NonEmpty (Exp (Maybe a)) -> Exp (Maybe a) # stimes :: Integral b => b -> Exp (Maybe a) -> Exp (Maybe a) #