Safe Haskell	Safe
Language	Haskell2010

Servant.Types.SourceT

Synopsis

newtype SourceT m a = SourceT {
- unSourceT :: forall b. (StepT m a -> m b) -> m b
}
mapStepT :: (StepT m a -> StepT m b) -> SourceT m a -> SourceT m b
data StepT m a
- = Stop
- | Error String
- | Skip (StepT m a)
- | Yield a (StepT m a)
- | Effect (m (StepT m a))
fromStepT :: StepT m a -> SourceT m a
source :: [a] -> SourceT m a
runSourceT :: Monad m => SourceT m a -> ExceptT String m [a]
runStepT :: Monad m => StepT m a -> ExceptT String m [a]
mapMaybe :: Functor m => (a -> Maybe b) -> SourceT m a -> SourceT m b
mapMaybeStep :: Functor m => (a -> Maybe b) -> StepT m a -> StepT m b
foreach :: Monad m => (String -> m ()) -> (a -> m ()) -> SourceT m a -> m ()
foreachStep :: Monad m => (String -> m ()) -> (a -> m ()) -> StepT m a -> m ()
fromAction :: Functor m => (a -> Bool) -> m a -> SourceT m a
fromActionStep :: Functor m => (a -> Bool) -> m a -> StepT m a
readFile :: FilePath -> SourceT IO ByteString
transformWithAtto :: Monad m => Parser a -> SourceT m ByteString -> SourceT m a
transformStepWithAtto :: forall a m. Monad m => Parser a -> StepT m ByteString -> StepT m a

Documentation

>>> :set -XOverloadedStrings
>>> import Control.Monad.Except (runExcept)
>>> import Data.Foldable (toList)
>>> import qualified Data.Attoparsec.ByteString.Char8 as A8

newtype SourceT m a Source #

This is CPSised ListT.

Since: 0.15

Constructors

SourceT
Fields unSourceT :: forall b. (StepT m a -> m b) -> m b

Instances

MonadIO m => FromSourceIO a (SourceT m a) Source #
Instance details Defined in Servant.API.Stream Methods fromSourceIO :: SourceIO a -> SourceT m a Source #
SourceToSourceIO m => ToSourceIO chunk (SourceT m chunk) Source #	Relax to use auxiliary class, have m
Instance details Defined in Servant.API.Stream Methods toSourceIO :: SourceT m chunk -> SourceIO chunk Source #
Functor m => Functor (SourceT m) Source #
Instance details Defined in Servant.Types.SourceT Methods fmap :: (a -> b) -> SourceT m a -> SourceT m b # (<$) :: a -> SourceT m b -> SourceT m a #
Identity ~ m => Foldable (SourceT m) Source #	`>>>` `toList (source [1..10])`[1,2,3,4,5,6,7,8,9,10]
Instance details Defined in Servant.Types.SourceT Methods fold :: Monoid m0 => SourceT m m0 -> m0 # foldMap :: Monoid m0 => (a -> m0) -> SourceT m a -> m0 # foldr :: (a -> b -> b) -> b -> SourceT m a -> b # foldr' :: (a -> b -> b) -> b -> SourceT m a -> b # foldl :: (b -> a -> b) -> b -> SourceT m a -> b # foldl' :: (b -> a -> b) -> b -> SourceT m a -> b # foldr1 :: (a -> a -> a) -> SourceT m a -> a # foldl1 :: (a -> a -> a) -> SourceT m a -> a # toList :: SourceT m a -> [a] # null :: SourceT m a -> Bool # length :: SourceT m a -> Int # elem :: Eq a => a -> SourceT m a -> Bool # maximum :: Ord a => SourceT m a -> a # minimum :: Ord a => SourceT m a -> a # sum :: Num a => SourceT m a -> a # product :: Num a => SourceT m a -> a #
(Applicative m, Show1 m) => Show1 (SourceT m) Source #
Instance details Defined in Servant.Types.SourceT Methods liftShowsPrec :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> Int -> SourceT m a -> ShowS # liftShowList :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> [SourceT m a] -> ShowS #
MFunctor SourceT Source #	`>>>` `hoist (Just . runIdentity) (source [1..3]) :: SourceT Maybe Int`fromStepT (Effect (Just (Yield 1 (Yield 2 (Yield 3 Stop)))))
Instance details Defined in Servant.Types.SourceT Methods hoist :: Monad m => (forall a. m a -> n a) -> SourceT m b -> SourceT n b #
(Applicative m, Show1 m, Show a) => Show (SourceT m a) Source #
Instance details Defined in Servant.Types.SourceT Methods showsPrec :: Int -> SourceT m a -> ShowS # show :: SourceT m a -> String # showList :: [SourceT m a] -> ShowS #
Functor m => Semigroup (SourceT m a) Source #	`>>>` `source "xy" <> source "z" :: SourceT Identity Char`fromStepT (Effect (Identity (Yield 'x' (Yield 'y' (Yield 'z' Stop)))))
Instance details Defined in Servant.Types.SourceT Methods (<>) :: SourceT m a -> SourceT m a -> SourceT m a # sconcat :: NonEmpty (SourceT m a) -> SourceT m a # stimes :: Integral b => b -> SourceT m a -> SourceT m a #
Functor m => Monoid (SourceT m a) Source #	`>>>` `mempty :: SourceT Maybe Int`fromStepT (Effect (Just Stop))
Instance details Defined in Servant.Types.SourceT Methods mempty :: SourceT m a # mappend :: SourceT m a -> SourceT m a -> SourceT m a # mconcat :: [SourceT m a] -> SourceT m a #
(Arbitrary a, Monad m) => Arbitrary (SourceT m a) Source #	Doesn't generate `Error` constructors. `SourceT` doesn't shrink.
Instance details Defined in Servant.Types.SourceT Methods arbitrary :: Gen (SourceT m a) # shrink :: SourceT m a -> [SourceT m a] #

mapStepT :: (StepT m a -> StepT m b) -> SourceT m a -> SourceT m b Source #

data StepT m a Source #

ListT with additional constructors.

Since: 0.15

Constructors

Stop
Error String
Skip (StepT m a)
Yield a (StepT m a)
Effect (m (StepT m a))

Instances

MonadTrans StepT Source #	`>>>` `lift [1,2,3] :: StepT [] Int`Effect [Yield 1 Stop,Yield 2 Stop,Yield 3 Stop]
Instance details Defined in Servant.Types.SourceT Methods lift :: Monad m => m a -> StepT m a #
Functor m => Functor (StepT m) Source #
Instance details Defined in Servant.Types.SourceT Methods fmap :: (a -> b) -> StepT m a -> StepT m b # (<$) :: a -> StepT m b -> StepT m a #
Identity ~ m => Foldable (StepT m) Source #
Instance details Defined in Servant.Types.SourceT Methods fold :: Monoid m0 => StepT m m0 -> m0 # foldMap :: Monoid m0 => (a -> m0) -> StepT m a -> m0 # foldr :: (a -> b -> b) -> b -> StepT m a -> b # foldr' :: (a -> b -> b) -> b -> StepT m a -> b # foldl :: (b -> a -> b) -> b -> StepT m a -> b # foldl' :: (b -> a -> b) -> b -> StepT m a -> b # foldr1 :: (a -> a -> a) -> StepT m a -> a # foldl1 :: (a -> a -> a) -> StepT m a -> a # toList :: StepT m a -> [a] # null :: StepT m a -> Bool # length :: StepT m a -> Int # elem :: Eq a => a -> StepT m a -> Bool # maximum :: Ord a => StepT m a -> a # minimum :: Ord a => StepT m a -> a # sum :: Num a => StepT m a -> a # product :: Num a => StepT m a -> a #
(Applicative m, Show1 m) => Show1 (StepT m) Source #
Instance details Defined in Servant.Types.SourceT Methods liftShowsPrec :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> Int -> StepT m a -> ShowS # liftShowList :: (Int -> a -> ShowS) -> ([a] -> ShowS) -> [StepT m a] -> ShowS #
MFunctor StepT Source #
Instance details Defined in Servant.Types.SourceT Methods hoist :: Monad m => (forall a. m a -> n a) -> StepT m b -> StepT n b #
(Applicative m, Show1 m, Show a) => Show (StepT m a) Source #
Instance details Defined in Servant.Types.SourceT Methods showsPrec :: Int -> StepT m a -> ShowS # show :: StepT m a -> String # showList :: [StepT m a] -> ShowS #
Functor m => Semigroup (StepT m a) Source #
Instance details Defined in Servant.Types.SourceT Methods (<>) :: StepT m a -> StepT m a -> StepT m a # sconcat :: NonEmpty (StepT m a) -> StepT m a # stimes :: Integral b => b -> StepT m a -> StepT m a #
Functor m => Monoid (StepT m a) Source #	`>>>` `mempty :: StepT [] Int`Stop `>>>` `mempty :: StepT Identity Int`Stop
Instance details Defined in Servant.Types.SourceT Methods mempty :: StepT m a # mappend :: StepT m a -> StepT m a -> StepT m a # mconcat :: [StepT m a] -> StepT m a #
(Arbitrary a, Monad m) => Arbitrary (StepT m a) Source #	Doesn't generate `Error` constructors.
Instance details Defined in Servant.Types.SourceT Methods arbitrary :: Gen (StepT m a) # shrink :: StepT m a -> [StepT m a] #

fromStepT :: StepT m a -> SourceT m a Source #

Create SourceT from Step.

Note: often enough you want to use SourceT directly.

source :: [a] -> SourceT m a Source #

Create pure SourceT.

>>> source "foo" :: SourceT Identity Char
fromStepT (Effect (Identity (Yield 'f' (Yield 'o' (Yield 'o' Stop)))))

runSourceT :: Monad m => SourceT m a -> ExceptT String m [a] Source #

Get the answers.

>>> runSourceT (source "foo" :: SourceT Identity Char)
ExceptT (Identity (Right "foo"))

>>> runSourceT (source "foo" :: SourceT [] Char)
ExceptT [Right "foo"]

runStepT :: Monad m => StepT m a -> ExceptT String m [a] Source #

mapMaybe :: Functor m => (a -> Maybe b) -> SourceT m a -> SourceT m b Source #

Filter values.

>>> toList $ mapMaybe (\x -> if odd x then Just x else Nothing) (source [0..10]) :: [Int]
[1,3,5,7,9]

>>> mapMaybe (\x -> if odd x then Just x else Nothing) (source [0..2]) :: SourceT Identity Int
fromStepT (Effect (Identity (Skip (Yield 1 (Skip Stop)))))

Illustrates why we need Skip.

mapMaybeStep :: Functor m => (a -> Maybe b) -> StepT m a -> StepT m b Source #

foreach Source #

Arguments

:: Monad m
=> (String -> m ())	error handler
-> (a -> m ())
-> SourceT m a
-> m ()

Run action for each value in the SourceT.

>>> foreach fail print (source "abc")
'a'
'b'
'c'

foreachStep Source #

Arguments

:: Monad m
=> (String -> m ())	error handler
-> (a -> m ())
-> StepT m a
-> m ()

See foreach.

fromAction :: Functor m => (a -> Bool) -> m a -> SourceT m a Source #

fromActionStep :: Functor m => (a -> Bool) -> m a -> StepT m a Source #

readFile :: FilePath -> SourceT IO ByteString Source #

Read file.

>>> foreach fail BS.putStr (readFile "servant.cabal")
cabal-version:       >=1.10
name:                servant
...

transformWithAtto :: Monad m => Parser a -> SourceT m ByteString -> SourceT m a Source #

Transform using attoparsec parser.

Note: parser should not accept empty input!

>>> let parser = A.skipWhile A8.isSpace_w8 >> A.takeWhile1 A8.isDigit_w8

>>> runExcept $ runSourceT $ transformWithAtto parser (source ["1 2 3"])
Right ["1","2","3"]

>>> runExcept $ runSourceT $ transformWithAtto parser (source ["1", "2", "3"])
Right ["123"]

>>> runExcept $ runSourceT $ transformWithAtto parser (source ["1", "2 3", "4"])
Right ["12","34"]

>>> runExcept $ runSourceT $ transformWithAtto parser (source ["foobar"])
Left "Failed reading: takeWhile1"

transformStepWithAtto :: forall a m. Monad m => Parser a -> StepT m ByteString -> StepT m a Source #