Feldspar.Data.Option

Optional values

Documentation

data OptionT m a

Transformer version of Option

Instances

MonadTrans OptionT

Defined in Feldspar.Data.Option

Methods

lift :: Monad m => m a -> OptionT m a

Monad m => Monad (OptionT m)

Defined in Feldspar.Data.Option

Methods

(>>=) :: OptionT m a -> (a -> OptionT m b) -> OptionT m b

(>>) :: OptionT m a -> OptionT m b -> OptionT m b

return :: a -> OptionT m a

Monad m => Functor (OptionT m)

Defined in Feldspar.Data.Option

Methods

fmap :: (a -> b) -> OptionT m a -> OptionT m b

(<$) :: a -> OptionT m b -> OptionT m a

Monad m => Applicative (OptionT m)

Defined in Feldspar.Data.Option

Methods

pure :: a -> OptionT m a

(<*>) :: OptionT m (a -> b) -> OptionT m a -> OptionT m b

liftA2 :: (a -> b -> c) -> OptionT m a -> OptionT m b -> OptionT m c

(*>) :: OptionT m a -> OptionT m b -> OptionT m b

(<*) :: OptionT m a -> OptionT m b -> OptionT m a

Syntax a => Syntactic (Option a)

Defined in Feldspar.Data.Option

Associated Types

type Domain (Option a) :: Type -> Type

type Internal (Option a)

Methods

desugar :: Option a -> ASTF (Domain (Option a)) (Internal (Option a))

sugar :: ASTF (Domain (Option a)) (Internal (Option a)) -> Option a

MonadComp m => MonadComp (OptionT m)

Defined in Feldspar.Data.Option

Methods

liftComp :: Comp a -> OptionT m a

iff :: Data Bool -> OptionT m () -> OptionT m () -> OptionT m ()

for :: (Integral n, PrimType n) => IxRange (Data n) -> (Data n -> OptionT m ()) -> OptionT m ()

while :: OptionT m (Data Bool) -> OptionT m () -> OptionT m ()

(Storable a, Syntax a, StoreSize a ~ ()) => Storable (Option a)

Defined in Feldspar.Data.Storable

Associated Types

type StoreRep (Option a)

type StoreSize (Option a)

Methods

newStoreRep :: MonadComp m => proxy (Option a) -> StoreSize (Option a) -> m (StoreRep (Option a))

initStoreRep :: MonadComp m => Option a -> m (StoreRep (Option a))

readStoreRep :: MonadComp m => StoreRep (Option a) -> m (Option a)

unsafeFreezeStoreRep :: MonadComp m => StoreRep (Option a) -> m (Option a)

writeStoreRep :: MonadComp m => StoreRep (Option a) -> Option a -> m ()

Syntax a => Forcible (Option a)

Defined in Feldspar.Data.Storable

Associated Types

type ValueRep (Option a)

Methods

toValue :: MonadComp m => Option a -> m (ValueRep (Option a))

fromValue :: ValueRep (Option a) -> Option a

type Internal (Option a)

Defined in Feldspar.Data.Option

type Internal (Option a) = (Bool, Internal a)

type Domain (Option a)

Defined in Feldspar.Data.Option

type Domain (Option a) = FeldDomain

type StoreRep (Option a)

Defined in Feldspar.Data.Storable

type StoreRep (Option a) = (DRef Bool, StoreRep a)

type StoreSize (Option a)

Defined in Feldspar.Data.Storable

type StoreSize (Option a) = ()

type ValueRep (Option a)

Defined in Feldspar.Data.Storable

type ValueRep (Option a) = (Data Bool, a)

type Option = OptionT Identity

Optional value, analogous to Either String a in normal Haskell

none :: String -> OptionT m a

Construct a missing Option value (analogous to Left in normal Haskell)

some :: Monad m => a -> OptionT m a

Construct a present Option value (analogous to Right in normal Haskell)

guardO :: String -> Data Bool -> OptionT m ()

Construct an Option that is either none or some () depending on the Boolean guard

In the expression guardO c >> rest, the action rest will not be executed unless c is true.

guarded :: Monad m => String -> Data Bool -> a -> OptionT m a

Construct an Option from a guard and a value. The value will not be evaluated if the guard is false.

rebuildOption :: Monad m => Option a -> OptionT m a

option

Arguments

:: Syntax b

=> (String -> b)

none case

-> (a -> b)

some case

-> Option a

-> b

Deconstruct an Option value (analogous to either in normal Haskell)

caseOption

Arguments

:: Syntax b

=> Option a

-> (String -> b)

none case

-> (a -> b)

some case

-> b

Deconstruct an Option value

fromSome :: Syntax a => Option a -> a

Extract the value of an Option that is assumed to be present

optionM

Arguments

:: MonadComp m

=> (String -> m ())

none case

-> (a -> m ())

some case

-> Option a

-> m ()

Deconstruct an Option value (analogous to maybe in normal Haskell)

caseOptionM

Arguments

:: MonadComp m

=> Option a

-> (String -> m ())

none case

-> (a -> m ())

some case

-> m ()

Deconstruct an Option value

fromSomeM :: (Syntax a, MonadComp m) => Option a -> m a

Extract the value of an Option that is assumed to be present

optionT

Arguments

:: MonadComp m

=> (String -> m ())

none case

-> (a -> m ())

some case

-> OptionT m a

-> m ()

Deconstruct an OptionT value

caseOptionT

Arguments

:: MonadComp m

=> OptionT m a

-> (String -> m ())

none case

-> (a -> m ())

some case

-> m ()

Deconstruct an OptionT value

fromSomeT :: (Syntax a, MonadComp m) => OptionT m a -> m a

Extract the value of an OptionT that is assumed to be present