Data.Option

Documentation

data Option a

Constructors

None

Some !a

Instances

Monad Option

Methods

(>>=) :: Option a -> (a -> Option b) -> Option b

(>>) :: Option a -> Option b -> Option b

return :: a -> Option a

fail :: String -> Option a

Functor Option

Methods

fmap :: (a -> b) -> Option a -> Option b

(<$) :: a -> Option b -> Option a

MonadFail Option

Methods

fail :: String -> Option a

Applicative Option

Methods

pure :: a -> Option a

(<*>) :: Option (a -> b) -> Option a -> Option b

(*>) :: Option a -> Option b -> Option b

(<*) :: Option a -> Option b -> Option a

Foldable Option

Methods

fold :: Monoid m => Option m -> m

foldMap :: Monoid m => (a -> m) -> Option a -> m

foldr :: (a -> b -> b) -> b -> Option a -> b

foldr' :: (a -> b -> b) -> b -> Option a -> b

foldl :: (b -> a -> b) -> b -> Option a -> b

foldl' :: (b -> a -> b) -> b -> Option a -> b

foldr1 :: (a -> a -> a) -> Option a -> a

foldl1 :: (a -> a -> a) -> Option a -> a

toList :: Option a -> [a]

null :: Option a -> Bool

length :: Option a -> Int

elem :: Eq a => a -> Option a -> Bool

maximum :: Ord a => Option a -> a

minimum :: Ord a => Option a -> a

sum :: Num a => Option a -> a

product :: Num a => Option a -> a

Traversable Option

Methods

traverse :: Applicative f => (a -> f b) -> Option a -> f (Option b)

sequenceA :: Applicative f => Option (f a) -> f (Option a)

mapM :: Monad m => (a -> m b) -> Option a -> m (Option b)

sequence :: Monad m => Option (m a) -> m (Option a)

Alternative Option

Methods

empty :: Option a

(<|>) :: Option a -> Option a -> Option a

some :: Option a -> Option [a]

many :: Option a -> Option [a]

MonadPlus Option

Methods

mzero :: Option a

mplus :: Option a -> Option a -> Option a

ToOptionT Option

Methods

optionT :: Monad m => m (Option a) -> OptionT m a

Eq a => Eq (Option a)

Methods

(==) :: Option a -> Option a -> Bool

(/=) :: Option a -> Option a -> Bool

Data a => Data (Option a)

Methods

gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Option a -> c (Option a)

gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Option a)

toConstr :: Option a -> Constr

dataTypeOf :: Option a -> DataType

dataCast1 :: Typeable (* -> *) t => (forall d. Data d => c (t d)) -> Maybe (c (Option a))

dataCast2 :: Typeable (* -> * -> *) t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Option a))

gmapT :: (forall b. Data b => b -> b) -> Option a -> Option a

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Option a -> r

gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Option a -> r

gmapQ :: (forall d. Data d => d -> u) -> Option a -> [u]

gmapQi :: Int -> (forall d. Data d => d -> u) -> Option a -> u

gmapM :: Monad m => (forall d. Data d => d -> m d) -> Option a -> m (Option a)

gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Option a -> m (Option a)

gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Option a -> m (Option a)

Ord a => Ord (Option a)

Methods

compare :: Option a -> Option a -> Ordering

(<) :: Option a -> Option a -> Bool

(<=) :: Option a -> Option a -> Bool

(>) :: Option a -> Option a -> Bool

(>=) :: Option a -> Option a -> Bool

max :: Option a -> Option a -> Option a

min :: Option a -> Option a -> Option a

Read a => Read (Option a)

Methods

readsPrec :: Int -> ReadS (Option a)

readList :: ReadS [Option a]

readPrec :: ReadPrec (Option a)

readListPrec :: ReadPrec [Option a]

Show a => Show (Option a)

Methods

showsPrec :: Int -> Option a -> ShowS

show :: Option a -> String

showList :: [Option a] -> ShowS

Generic (Option a)

Associated Types

type Rep (Option a) :: * -> *

Methods

from :: Option a -> Rep (Option a) x

to :: Rep (Option a) x -> Option a

Monoid a => Monoid (Option a)

Methods

mempty :: Option a

mappend :: Option a -> Option a -> Option a

mconcat :: [Option a] -> Option a

Arbitrary a => Arbitrary (Option a)

Methods

arbitrary :: Gen (Option a)

shrink :: Option a -> [Option a]

Hashable a => Hashable (Option a)

Methods

hashWithSalt :: Int -> Option a -> Int

hash :: Option a -> Int

ToJSON a => ToJSON (Option a)

Methods

toJSON :: Option a -> Value

toEncoding :: Option a -> Encoding

toJSONList :: [Option a] -> Value

toEncodingList :: [Option a] -> Encoding

FromJSON a => FromJSON (Option a)

Methods

parseJSON :: Value -> Parser (Option a)

parseJSONList :: Value -> Parser [Option a]

NFData a => NFData (Option a)

Methods

rnf :: Option a -> ()

type Rep (Option a)

type Rep (Option a) = D1 (MetaData "Option" "Data.Option" "strict-data-0.2.0.2-FGPF9cVJpblGQAsBKh3DLB" False) ((:+:) (C1 (MetaCons "None" PrefixI False) U1) (C1 (MetaCons "Some" PrefixI False) (S1 (MetaSel (Nothing Symbol) NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 a))))

newtype OptionT m a

Constructors

OptionT

Fields

• runOptionT :: m (Option a)

Instances

MonadTrans OptionT

Methods

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

Monad m => Monad (OptionT m)

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

fail :: String -> OptionT m a

Functor m => Functor (OptionT m)

Methods

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

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

Monad m => MonadFail (OptionT m)

Methods

fail :: String -> OptionT m a

(Functor m, Monad m) => Applicative (OptionT m)

Methods

pure :: a -> OptionT m a

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

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

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

MonadIO m => MonadIO (OptionT m)

Methods

liftIO :: IO a -> OptionT m a

runOptionTDef :: Functor m => a -> OptionT m a -> m a

class ToOptionT t where

Minimal complete definition

optionT

Methods

optionT :: Monad m => m (t a) -> OptionT m a

Instances

ToOptionT Maybe

Methods

optionT :: Monad m => m (Maybe a) -> OptionT m a

ToOptionT Option

Methods

optionT :: Monad m => m (Option a) -> OptionT m a

noneIf :: (a -> Bool) -> a -> Option a

fromOption :: a -> Option a -> a

isSome :: Option a -> Bool

isNone :: Option a -> Bool

optionToMaybe :: Option a -> Maybe a

maybeToOption :: Maybe a -> Option a

maybeToOption (optionToMaybe x) == x

optionToList :: Option a -> [a]

optionToSL :: Option a -> StrictList a

listToOption :: [a] -> Option a

getSomeNote :: Monad m => String -> Option a -> m a

option :: b -> (a -> b) -> Option a -> b

catOptions :: [Option a] -> [a]

mapOption :: (a -> Option b) -> [a] -> [b]

forOptionM :: Monad m => [a] -> (a -> OptionT m b) -> m [b]

mapOptionM :: Monad m => (a -> OptionT m b) -> [a] -> m [b]

safeFromSome :: Option a -> a

failToOption :: Fail a -> Option a

optionToFail :: String -> Option a -> Fail a

optionToFailT :: Monad m => String -> Option a -> FailT m a