| Safe Haskell | None |
|---|---|
| Language | Haskell2010 |
Bio.Streaming
Contents
Synopsis
- class Monad m => MonadIO (m :: Type -> Type) where
- class MonadCatch m => MonadMask (m :: Type -> Type)
- data ByteStream m r
- streamFile :: (MonadIO m, MonadMask m) => FilePath -> (ByteStream m () -> m r) -> m r
- streamHandle :: MonadIO m => Handle -> ByteStream m ()
- streamInput :: (MonadIO m, MonadMask m) => FilePath -> (ByteStream m () -> m r) -> m r
- streamInputs :: MonadIO m => [FilePath] -> (Stream (ByteStream m) m () -> r) -> r
- withOutputFile :: (MonadIO m, MonadMask m) => FilePath -> (Handle -> m a) -> m a
- data UnwantedTerminal = UnwantedTerminal
- protectTerm :: (Functor f, MonadIO m) => Stream f m r -> Stream f m r
- psequence :: MonadIO m => Int -> Stream (Of (IO a)) m b -> Stream (Of a) m b
- progressGen :: MonadLog m => (Int -> a -> String) -> Int -> Stream (Of a) m r -> Stream (Of a) m r
- progressNum :: MonadLog m => String -> Int -> Stream (Of a) m r -> Stream (Of a) m r
- progressPos :: MonadLog m => (a -> (Refseq, Int)) -> String -> Refs -> Int -> Stream (Of a) m r -> Stream (Of a) m r
- mergeStreams :: (Monad m, Ord a) => Stream (Of a) m r -> Stream (Of a) m s -> Stream (Of a) m (r, s)
- mergeStreamsBy :: Monad m => (a -> a -> Ordering) -> Stream (Of a) m r -> Stream (Of a) m s -> Stream (Of a) m (r, s)
- mergeStreamsOn :: (Monad m, Ord b) => (a -> b) -> Stream (Of a) m r -> Stream (Of a) m s -> Stream (Of a) m (r, s)
- join :: Monad m => m (m a) -> m a
- liftA2 :: Applicative f => (a -> b -> c) -> f a -> f b -> f c
- class Applicative f => Alternative (f :: Type -> Type) where
- (<|>) :: f a -> f a -> f a
- newtype Compose (f :: k -> Type) (g :: k1 -> k) (a :: k1) = Compose {
- getCompose :: f (g a)
- data Sum (f :: k -> Type) (g :: k -> Type) (a :: k)
- class Bifunctor (p :: Type -> Type -> Type) where
- class Monad m => MonadIO (m :: Type -> Type) where
- newtype Identity a = Identity {
- runIdentity :: a
- void :: Functor f => f a -> f ()
- liftM2 :: Monad m => (a1 -> a2 -> r) -> m a1 -> m a2 -> m r
- liftM :: Monad m => (a1 -> r) -> m a1 -> m r
- liftA3 :: Applicative f => (a -> b -> c -> d) -> f a -> f b -> f c -> f d
- class MFunctor (t :: (Type -> Type) -> k -> Type) where
- class (MFunctor t, MonadTrans t) => MMonad (t :: (Type -> Type) -> Type -> Type) where
- class MonadTrans (t :: (Type -> Type) -> Type -> Type) where
- mappedPost :: (Monad m, Functor g) => (forall x. f x -> m (g x)) -> Stream f m r -> Stream g m r
- mapped :: (Monad m, Functor f) => (forall x. f x -> m (g x)) -> Stream f m r -> Stream g m r
- strictly :: (a, b) -> Of a b
- lazily :: Of a b -> (a, b)
- cutoff :: forall (m :: Type -> Type) (f :: Type -> Type) r. (Monad m, Functor f) => Int -> Stream f m r -> Stream f m (Maybe r)
- untilJust :: forall m (f :: Type -> Type) r. (Monad m, Applicative f) => m (Maybe r) -> Stream f m r
- delays :: forall (m :: Type -> Type) (f :: Type -> Type) r. (MonadIO m, Applicative f) => Double -> Stream f m r
- never :: forall (m :: Type -> Type) (f :: Type -> Type) r. (Monad m, Applicative f) => Stream f m r
- groups :: forall (m :: Type -> Type) (f :: Type -> Type) (g :: Type -> Type) r. (Monad m, Functor f, Functor g) => Stream (Sum f g) m r -> Stream (Sum (Stream f m) (Stream g m)) m r
- unzips :: forall (m :: Type -> Type) (f :: Type -> Type) (g :: Type -> Type) r. (Monad m, Functor f, Functor g) => Stream (Compose f g) m r -> Stream f (Stream g m) r
- expandPost :: forall (m :: Type -> Type) g f h r. (Monad m, Functor g) => (forall a b. (g a -> b) -> f a -> h b) -> Stream f m r -> Stream g (Stream h m) r
- expand :: forall (m :: Type -> Type) f g h r. (Monad m, Functor f) => (forall a b. (g a -> b) -> f a -> h b) -> Stream f m r -> Stream g (Stream h m) r
- unseparate :: forall (m :: Type -> Type) (f :: Type -> Type) (g :: Type -> Type) r. (Monad m, Functor f, Functor g) => Stream f (Stream g m) r -> Stream (Sum f g) m r
- separate :: forall (m :: Type -> Type) (f :: Type -> Type) (g :: Type -> Type) r. (Monad m, Functor f, Functor g) => Stream (Sum f g) m r -> Stream f (Stream g m) r
- interleaves :: forall (m :: Type -> Type) (h :: Type -> Type) r. (Monad m, Applicative h) => Stream h m r -> Stream h m r -> Stream h m r
- zips :: forall (m :: Type -> Type) (f :: Type -> Type) (g :: Type -> Type) r. (Monad m, Functor f, Functor g) => Stream f m r -> Stream g m r -> Stream (Compose f g) m r
- zipsWith' :: forall f g h (m :: Type -> Type) r. Monad m => (forall x y p. (x -> y -> p) -> f x -> g y -> h p) -> Stream f m r -> Stream g m r -> Stream h m r
- zipsWith :: forall f g h (m :: Type -> Type) r. (Monad m, Functor h) => (forall x y. f x -> g y -> h (x, y)) -> Stream f m r -> Stream g m r -> Stream h m r
- yields :: forall (m :: Type -> Type) f r. (Monad m, Functor f) => f r -> Stream f m r
- effect :: forall m (f :: Type -> Type) r. (Monad m, Functor f) => m (Stream f m r) -> Stream f m r
- wrap :: forall (m :: Type -> Type) f r. (Monad m, Functor f) => f (Stream f m r) -> Stream f m r
- hoistUnexposed :: forall m (f :: Type -> Type) n r. (Monad m, Functor f) => (forall a. m a -> n a) -> Stream f m r -> Stream f n r
- replicates :: forall (m :: Type -> Type) f. (Monad m, Functor f) => Int -> f () -> Stream f m ()
- repeatsM :: (Monad m, Functor f) => m (f ()) -> Stream f m r
- repeats :: forall (m :: Type -> Type) f r. (Monad m, Functor f) => f () -> Stream f m r
- distribute :: forall (m :: Type -> Type) (f :: Type -> Type) t r. (Monad m, Functor f, MonadTrans t, MFunctor t, Monad (t (Stream f m))) => Stream f (t m) r -> t (Stream f m) r
- chunksOf :: forall (m :: Type -> Type) (f :: Type -> Type) r. (Monad m, Functor f) => Int -> Stream f m r -> Stream (Stream f m) m r
- takes :: forall (m :: Type -> Type) (f :: Type -> Type) r. (Monad m, Functor f) => Int -> Stream f m r -> Stream f m ()
- splitsAt :: forall (m :: Type -> Type) (f :: Type -> Type) r. (Monad m, Functor f) => Int -> Stream f m r -> Stream f m (Stream f m r)
- concats :: forall (m :: Type -> Type) (f :: Type -> Type) r. (Monad m, Functor f) => Stream (Stream f m) m r -> Stream f m r
- iterT :: (Functor f, Monad m) => (f (m a) -> m a) -> Stream f m a -> m a
- iterTM :: forall f (m :: Type -> Type) t a. (Functor f, Monad m, MonadTrans t, Monad (t m)) => (f (t m a) -> t m a) -> Stream f m a -> t m a
- intercalates :: forall (m :: Type -> Type) t x r. (Monad m, Monad (t m), MonadTrans t) => t m x -> Stream (t m) m r -> t m r
- mapsM_ :: (Functor f, Monad m) => (forall x. f x -> m x) -> Stream f m r -> m r
- run :: Monad m => Stream m m r -> m r
- decompose :: forall (m :: Type -> Type) (f :: Type -> Type) r. (Monad m, Functor f) => Stream (Compose m f) m r -> Stream f m r
- mapsMPost :: forall m f g r. (Monad m, Functor g) => (forall x. f x -> m (g x)) -> Stream f m r -> Stream g m r
- mapsPost :: forall (m :: Type -> Type) f g r. (Monad m, Functor g) => (forall x. f x -> g x) -> Stream f m r -> Stream g m r
- mapsM :: (Monad m, Functor f) => (forall x. f x -> m (g x)) -> Stream f m r -> Stream g m r
- maps :: forall (m :: Type -> Type) f g r. (Monad m, Functor f) => (forall x. f x -> g x) -> Stream f m r -> Stream g m r
- unfold :: (Monad m, Functor f) => (s -> m (Either r (f s))) -> s -> Stream f m r
- inspect :: Monad m => Stream f m r -> m (Either r (f (Stream f m r)))
- streamBuild :: (forall b. (r -> b) -> (m b -> b) -> (f b -> b) -> b) -> Stream f m r
- streamFold :: (Functor f, Monad m) => (r -> b) -> (m b -> b) -> (f b -> b) -> Stream f m r -> b
- destroy :: (Functor f, Monad m) => Stream f m r -> (f b -> b) -> (m b -> b) -> (r -> b) -> b
- data Stream (f :: Type -> Type) (m :: Type -> Type) r
- data Of a b = !a :> b
- each :: forall (m :: Type -> Type) f a. (Monad m, Foldable f) => f a -> Stream (Of a) m ()
Documentation
class Monad m => MonadIO (m :: Type -> Type) where #
Monads in which IO computations may be embedded.
Any monad built by applying a sequence of monad transformers to the
IO monad will be an instance of this class.
Instances should satisfy the following laws, which state that liftIO
is a transformer of monads:
Instances
class MonadCatch m => MonadMask (m :: Type -> Type) #
A class for monads which provide for the ability to account for all possible exit points from a computation, and to mask asynchronous exceptions. Continuation-based monads are invalid instances of this class.
Instances should ensure that, in the following code:
fg = f `finally` g
The action g is called regardless of what occurs within f, including
async exceptions. Some monads allow f to abort the computation via other
effects than throwing an exception. For simplicity, we will consider aborting
and throwing an exception to be two forms of "throwing an error".
If f and g both throw an error, the error thrown by fg depends on which
errors we're talking about. In a monad transformer stack, the deeper layers
override the effects of the inner layers; for example, ExceptT e1 (Except
e2) a represents a value of type Either e2 (Either e1 a), so throwing both
an e1 and an e2 will result in Left e2. If f and g both throw an
error from the same layer, instances should ensure that the error from g
wins.
Effects other than throwing an error are also overriden by the deeper layers.
For example, StateT s Maybe a represents a value of type s -> Maybe (a,
s), so if an error thrown from f causes this function to return Nothing,
any changes to the state which f also performed will be erased. As a
result, g will see the state as it was before f. Once g completes,
f's error will be rethrown, so g' state changes will be erased as well.
This is the normal interaction between effects in a monad transformer stack.
By contrast, lifted-base's
version of finally always discards all of g's non-IO effects, and g
never sees any of f's non-IO effects, regardless of the layer ordering and
regardless of whether f throws an error. This is not the result of
interacting effects, but a consequence of MonadBaseControl's approach.
Minimal complete definition
Instances
| MonadMask IO | |
| e ~ SomeException => MonadMask (Either e) | Since: exceptions-0.8.3 |
Defined in Control.Monad.Catch | |
| MonadMask m => MonadMask (MaybeT m) | Since: exceptions-0.10.0 |
Defined in Control.Monad.Catch | |
| MonadMask m => MonadMask (Logged m) Source # | |
Defined in Control.Monad.Log | |
| MonadMask m => MonadMask (ExceptT e m) | Since: exceptions-0.9.0 |
Defined in Control.Monad.Catch Methods mask :: ((forall a. ExceptT e m a -> ExceptT e m a) -> ExceptT e m b) -> ExceptT e m b # uninterruptibleMask :: ((forall a. ExceptT e m a -> ExceptT e m a) -> ExceptT e m b) -> ExceptT e m b # generalBracket :: ExceptT e m a -> (a -> ExitCase b -> ExceptT e m c) -> (a -> ExceptT e m b) -> ExceptT e m (b, c) # | |
| (MonadMask m, Monoid w) => MonadMask (WriterT w m) | |
Defined in Control.Monad.Catch Methods mask :: ((forall a. WriterT w m a -> WriterT w m a) -> WriterT w m b) -> WriterT w m b # uninterruptibleMask :: ((forall a. WriterT w m a -> WriterT w m a) -> WriterT w m b) -> WriterT w m b # generalBracket :: WriterT w m a -> (a -> ExitCase b -> WriterT w m c) -> (a -> WriterT w m b) -> WriterT w m (b, c) # | |
| MonadMask m => MonadMask (StateT s m) | |
Defined in Control.Monad.Catch Methods mask :: ((forall a. StateT s m a -> StateT s m a) -> StateT s m b) -> StateT s m b # uninterruptibleMask :: ((forall a. StateT s m a -> StateT s m a) -> StateT s m b) -> StateT s m b # generalBracket :: StateT s m a -> (a -> ExitCase b -> StateT s m c) -> (a -> StateT s m b) -> StateT s m (b, c) # | |
| MonadMask m => MonadMask (ReaderT r m) | |
Defined in Control.Monad.Catch Methods mask :: ((forall a. ReaderT r m a -> ReaderT r m a) -> ReaderT r m b) -> ReaderT r m b # uninterruptibleMask :: ((forall a. ReaderT r m a -> ReaderT r m a) -> ReaderT r m b) -> ReaderT r m b # generalBracket :: ReaderT r m a -> (a -> ExitCase b -> ReaderT r m c) -> (a -> ReaderT r m b) -> ReaderT r m (b, c) # | |
| (Error e, MonadMask m) => MonadMask (ErrorT e m) | |
Defined in Control.Monad.Catch Methods mask :: ((forall a. ErrorT e m a -> ErrorT e m a) -> ErrorT e m b) -> ErrorT e m b # uninterruptibleMask :: ((forall a. ErrorT e m a -> ErrorT e m a) -> ErrorT e m b) -> ErrorT e m b # generalBracket :: ErrorT e m a -> (a -> ExitCase b -> ErrorT e m c) -> (a -> ErrorT e m b) -> ErrorT e m (b, c) # | |
| MonadMask m => MonadMask (IdentityT m) | |
Defined in Control.Monad.Catch Methods mask :: ((forall a. IdentityT m a -> IdentityT m a) -> IdentityT m b) -> IdentityT m b # uninterruptibleMask :: ((forall a. IdentityT m a -> IdentityT m a) -> IdentityT m b) -> IdentityT m b # generalBracket :: IdentityT m a -> (a -> ExitCase b -> IdentityT m c) -> (a -> IdentityT m b) -> IdentityT m (b, c) # | |
| MonadMask m => MonadMask (StateT s m) | |
Defined in Control.Monad.Catch Methods mask :: ((forall a. StateT s m a -> StateT s m a) -> StateT s m b) -> StateT s m b # uninterruptibleMask :: ((forall a. StateT s m a -> StateT s m a) -> StateT s m b) -> StateT s m b # generalBracket :: StateT s m a -> (a -> ExitCase b -> StateT s m c) -> (a -> StateT s m b) -> StateT s m (b, c) # | |
| (MonadMask m, Monoid w) => MonadMask (WriterT w m) | |
Defined in Control.Monad.Catch Methods mask :: ((forall a. WriterT w m a -> WriterT w m a) -> WriterT w m b) -> WriterT w m b # uninterruptibleMask :: ((forall a. WriterT w m a -> WriterT w m a) -> WriterT w m b) -> WriterT w m b # generalBracket :: WriterT w m a -> (a -> ExitCase b -> WriterT w m c) -> (a -> WriterT w m b) -> WriterT w m (b, c) # | |
| (MonadMask m, Monoid w) => MonadMask (RWST r w s m) | |
Defined in Control.Monad.Catch Methods mask :: ((forall a. RWST r w s m a -> RWST r w s m a) -> RWST r w s m b) -> RWST r w s m b # uninterruptibleMask :: ((forall a. RWST r w s m a -> RWST r w s m a) -> RWST r w s m b) -> RWST r w s m b # generalBracket :: RWST r w s m a -> (a -> ExitCase b -> RWST r w s m c) -> (a -> RWST r w s m b) -> RWST r w s m (b, c) # | |
| (MonadMask m, Monoid w) => MonadMask (RWST r w s m) | |
Defined in Control.Monad.Catch Methods mask :: ((forall a. RWST r w s m a -> RWST r w s m a) -> RWST r w s m b) -> RWST r w s m b # uninterruptibleMask :: ((forall a. RWST r w s m a -> RWST r w s m a) -> RWST r w s m b) -> RWST r w s m b # generalBracket :: RWST r w s m a -> (a -> ExitCase b -> RWST r w s m c) -> (a -> RWST r w s m b) -> RWST r w s m (b, c) # | |
data ByteStream m r Source #
A space-efficient representation of a succession of Word8 vectors, supporting many
efficient operations.
An effectful ByteStream contains 8-bit bytes, or by using certain
operations can be interpreted as containing 8-bit characters. It
also contains an offset, which will be needed to track the virtual
offsets in the BGZF decode.
Instances
streamFile :: (MonadIO m, MonadMask m) => FilePath -> (ByteStream m () -> m r) -> m r Source #
streamHandle :: MonadIO m => Handle -> ByteStream m () Source #
streamInput :: (MonadIO m, MonadMask m) => FilePath -> (ByteStream m () -> m r) -> m r Source #
Reads stdin if the filename is "-", else reads the named file.
streamInputs :: MonadIO m => [FilePath] -> (Stream (ByteStream m) m () -> r) -> r Source #
Reads multiple inputs in sequence.
Only one file is opened at a time, so they must also be consumed in sequence. The filename "-" refers to stdin, if no filenames are given, stdin is read.
data UnwantedTerminal Source #
Constructors
| UnwantedTerminal |
Instances
| Show UnwantedTerminal Source # | |
Defined in Bio.Streaming Methods showsPrec :: Int -> UnwantedTerminal -> ShowS # show :: UnwantedTerminal -> String # showList :: [UnwantedTerminal] -> ShowS # | |
| Exception UnwantedTerminal Source # | |
Defined in Bio.Streaming Methods toException :: UnwantedTerminal -> SomeException # | |
progressGen :: MonadLog m => (Int -> a -> String) -> Int -> Stream (Of a) m r -> Stream (Of a) m r Source #
A general progress indicator that logs some message after a set number of records have passed through.
progressNum :: MonadLog m => String -> Int -> Stream (Of a) m r -> Stream (Of a) m r Source #
A simple progress indicator that logs the number of records.
progressPos :: MonadLog m => (a -> (Refseq, Int)) -> String -> Refs -> Int -> Stream (Of a) m r -> Stream (Of a) m r Source #
A simple progress indicator that logs a position every set number of passed records.
mergeStreams :: (Monad m, Ord a) => Stream (Of a) m r -> Stream (Of a) m s -> Stream (Of a) m (r, s) Source #
mergeStreamsBy :: Monad m => (a -> a -> Ordering) -> Stream (Of a) m r -> Stream (Of a) m s -> Stream (Of a) m (r, s) Source #
mergeStreamsOn :: (Monad m, Ord b) => (a -> b) -> Stream (Of a) m r -> Stream (Of a) m s -> Stream (Of a) m (r, s) Source #
join :: Monad m => m (m a) -> m a #
The join function is the conventional monad join operator. It
is used to remove one level of monadic structure, projecting its
bound argument into the outer level.
Examples
A common use of join is to run an IO computation returned from
an STM transaction, since STM transactions
can't perform IO directly. Recall that
atomically :: STM a -> IO a
is used to run STM transactions atomically. So, by
specializing the types of atomically and join to
atomically:: STM (IO b) -> IO (IO b)join:: IO (IO b) -> IO b
we can compose them as
join.atomically:: STM (IO b) -> IO b
liftA2 :: Applicative f => (a -> b -> c) -> f a -> f b -> f c #
class Applicative f => Alternative (f :: Type -> Type) where #
A monoid on applicative functors.
If defined, some and many should be the least solutions
of the equations:
Instances
newtype Compose (f :: k -> Type) (g :: k1 -> k) (a :: k1) infixr 9 #
Right-to-left composition of functors. The composition of applicative functors is always applicative, but the composition of monads is not always a monad.
Constructors
| Compose infixr 9 | |
Fields
| |
Instances
| Functor f => Generic1 (Compose f g :: k -> Type) | Since: base-4.9.0.0 |
| Functor f => MFunctor (Compose f :: (Type -> Type) -> Type -> Type) | |
| (Functor f, Functor g) => Functor (Compose f g) | Since: base-4.9.0.0 |
| (Applicative f, Applicative g) => Applicative (Compose f g) | Since: base-4.9.0.0 |
Defined in Data.Functor.Compose | |
| (Foldable f, Foldable g) => Foldable (Compose f g) | Since: base-4.9.0.0 |
Defined in Data.Functor.Compose Methods fold :: Monoid m => Compose f g m -> m # foldMap :: Monoid m => (a -> m) -> Compose f g a -> m # foldMap' :: Monoid m => (a -> m) -> Compose f g a -> m # foldr :: (a -> b -> b) -> b -> Compose f g a -> b # foldr' :: (a -> b -> b) -> b -> Compose f g a -> b # foldl :: (b -> a -> b) -> b -> Compose f g a -> b # foldl' :: (b -> a -> b) -> b -> Compose f g a -> b # foldr1 :: (a -> a -> a) -> Compose f g a -> a # foldl1 :: (a -> a -> a) -> Compose f g a -> a # toList :: Compose f g a -> [a] # null :: Compose f g a -> Bool # length :: Compose f g a -> Int # elem :: Eq a => a -> Compose f g a -> Bool # maximum :: Ord a => Compose f g a -> a # minimum :: Ord a => Compose f g a -> a # | |
| (Traversable f, Traversable g) => Traversable (Compose f g) | Since: base-4.9.0.0 |
Defined in Data.Functor.Compose | |
| (Alternative f, Applicative g) => Alternative (Compose f g) | Since: base-4.9.0.0 |
| (Eq1 f, Eq1 g) => Eq1 (Compose f g) | Since: base-4.9.0.0 |
| (Ord1 f, Ord1 g) => Ord1 (Compose f g) | Since: base-4.9.0.0 |
Defined in Data.Functor.Compose | |
| (Read1 f, Read1 g) => Read1 (Compose f g) | Since: base-4.9.0.0 |
Defined in Data.Functor.Compose Methods liftReadsPrec :: (Int -> ReadS a) -> ReadS [a] -> Int -> ReadS (Compose f g a) # liftReadList :: (Int -> ReadS a) -> ReadS [a] -> ReadS [Compose f g a] # liftReadPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec (Compose f g a) # liftReadListPrec :: ReadPrec a -> ReadPrec [a] -> ReadPrec [Compose f g a] # | |
| (Show1 f, Show1 g) => Show1 (Compose f g) | Since: base-4.9.0.0 |
| (Hashable1 f, Hashable1 g) => Hashable1 (Compose f g) | |
Defined in Data.Hashable.Class | |
| (Eq1 f, Eq1 g, Eq a) => Eq (Compose f g a) | Since: base-4.9.0.0 |
| (Typeable a, Typeable f, Typeable g, Typeable k1, Typeable k2, Data (f (g a))) => Data (Compose f g a) | Since: base-4.9.0.0 |
Defined in Data.Functor.Compose Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g0. g0 -> c g0) -> Compose f g a -> c (Compose f g a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Compose f g a) # toConstr :: Compose f g a -> Constr # dataTypeOf :: Compose f g a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Compose f g a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Compose f g a)) # gmapT :: (forall b. Data b => b -> b) -> Compose f g a -> Compose f g a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Compose f g a -> r # gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Compose f g a -> r # gmapQ :: (forall d. Data d => d -> u) -> Compose f g a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Compose f g a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Compose f g a -> m (Compose f g a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Compose f g a -> m (Compose f g a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Compose f g a -> m (Compose f g a) # | |
| (Ord1 f, Ord1 g, Ord a) => Ord (Compose f g a) | Since: base-4.9.0.0 |
Defined in Data.Functor.Compose Methods compare :: Compose f g a -> Compose f g a -> Ordering # (<) :: Compose f g a -> Compose f g a -> Bool # (<=) :: Compose f g a -> Compose f g a -> Bool # (>) :: Compose f g a -> Compose f g a -> Bool # (>=) :: Compose f g a -> Compose f g a -> Bool # | |
| (Read1 f, Read1 g, Read a) => Read (Compose f g a) | Since: base-4.9.0.0 |
| (Show1 f, Show1 g, Show a) => Show (Compose f g a) | Since: base-4.9.0.0 |
| Generic (Compose f g a) | Since: base-4.9.0.0 |
| (Hashable1 f, Hashable1 g, Hashable a) => Hashable (Compose f g a) | In general, |
Defined in Data.Hashable.Class | |
| type Rep1 (Compose f g :: k -> Type) | |
Defined in Data.Functor.Compose | |
| type Rep (Compose f g a) | |
Defined in Data.Functor.Compose | |
data Sum (f :: k -> Type) (g :: k -> Type) (a :: k) #
Lifted sum of functors.
Instances
| Generic1 (Sum f g :: k -> Type) | Since: base-4.9.0.0 |
| (Functor f, Functor g) => Functor (Sum f g) | Since: base-4.9.0.0 |
| (Foldable f, Foldable g) => Foldable (Sum f g) | Since: base-4.9.0.0 |
Defined in Data.Functor.Sum Methods fold :: Monoid m => Sum f g m -> m # foldMap :: Monoid m => (a -> m) -> Sum f g a -> m # foldMap' :: Monoid m => (a -> m) -> Sum f g a -> m # foldr :: (a -> b -> b) -> b -> Sum f g a -> b # foldr' :: (a -> b -> b) -> b -> Sum f g a -> b # foldl :: (b -> a -> b) -> b -> Sum f g a -> b # foldl' :: (b -> a -> b) -> b -> Sum f g a -> b # foldr1 :: (a -> a -> a) -> Sum f g a -> a # foldl1 :: (a -> a -> a) -> Sum f g a -> a # elem :: Eq a => a -> Sum f g a -> Bool # maximum :: Ord a => Sum f g a -> a # minimum :: Ord a => Sum f g a -> a # | |
| (Traversable f, Traversable g) => Traversable (Sum f g) | Since: base-4.9.0.0 |
| (Eq1 f, Eq1 g) => Eq1 (Sum f g) | Since: base-4.9.0.0 |
| (Ord1 f, Ord1 g) => Ord1 (Sum f g) | Since: base-4.9.0.0 |
Defined in Data.Functor.Sum | |
| (Read1 f, Read1 g) => Read1 (Sum f g) | Since: base-4.9.0.0 |
Defined in Data.Functor.Sum | |
| (Show1 f, Show1 g) => Show1 (Sum f g) | Since: base-4.9.0.0 |
| (Hashable1 f, Hashable1 g) => Hashable1 (Sum f g) | |
Defined in Data.Hashable.Class | |
| (Eq1 f, Eq1 g, Eq a) => Eq (Sum f g a) | Since: base-4.9.0.0 |
| (Typeable a, Typeable f, Typeable g, Typeable k, Data (f a), Data (g a)) => Data (Sum f g a) | Since: base-4.9.0.0 |
Defined in Data.Functor.Sum Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g0. g0 -> c g0) -> Sum f g a -> c (Sum f g a) # gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Sum f g a) # toConstr :: Sum f g a -> Constr # dataTypeOf :: Sum f g a -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Sum f g a)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Sum f g a)) # gmapT :: (forall b. Data b => b -> b) -> Sum f g a -> Sum f g a # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Sum f g a -> r # gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Sum f g a -> r # gmapQ :: (forall d. Data d => d -> u) -> Sum f g a -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Sum f g a -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Sum f g a -> m (Sum f g a) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Sum f g a -> m (Sum f g a) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Sum f g a -> m (Sum f g a) # | |
| (Ord1 f, Ord1 g, Ord a) => Ord (Sum f g a) | Since: base-4.9.0.0 |
| (Read1 f, Read1 g, Read a) => Read (Sum f g a) | Since: base-4.9.0.0 |
| (Show1 f, Show1 g, Show a) => Show (Sum f g a) | Since: base-4.9.0.0 |
| Generic (Sum f g a) | Since: base-4.9.0.0 |
| (Hashable1 f, Hashable1 g, Hashable a) => Hashable (Sum f g a) | |
Defined in Data.Hashable.Class | |
| type Rep1 (Sum f g :: k -> Type) | |
Defined in Data.Functor.Sum type Rep1 (Sum f g :: k -> Type) = D1 ('MetaData "Sum" "Data.Functor.Sum" "base" 'False) (C1 ('MetaCons "InL" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec1 f)) :+: C1 ('MetaCons "InR" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec1 g))) | |
| type Rep (Sum f g a) | |
Defined in Data.Functor.Sum type Rep (Sum f g a) = D1 ('MetaData "Sum" "Data.Functor.Sum" "base" 'False) (C1 ('MetaCons "InL" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (f a))) :+: C1 ('MetaCons "InR" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (g a)))) | |
class Bifunctor (p :: Type -> Type -> Type) where #
A bifunctor is a type constructor that takes
two type arguments and is a functor in both arguments. That
is, unlike with Functor, a type constructor such as Either
does not need to be partially applied for a Bifunctor
instance, and the methods in this class permit mapping
functions over the Left value or the Right value,
or both at the same time.
Formally, the class Bifunctor represents a bifunctor
from Hask -> Hask.
Intuitively it is a bifunctor where both the first and second arguments are covariant.
You can define a Bifunctor by either defining bimap or by
defining both first and second.
If you supply bimap, you should ensure that:
bimapidid≡id
If you supply first and second, ensure:
firstid≡idsecondid≡id
If you supply both, you should also ensure:
bimapf g ≡firstf.secondg
These ensure by parametricity:
bimap(f.g) (h.i) ≡bimapf h.bimapg ifirst(f.g) ≡firstf.firstgsecond(f.g) ≡secondf.secondg
Since: base-4.8.0.0
Methods
bimap :: (a -> b) -> (c -> d) -> p a c -> p b d #
Map over both arguments at the same time.
bimapf g ≡firstf.secondg
Examples
>>>bimap toUpper (+1) ('j', 3)('J',4)
>>>bimap toUpper (+1) (Left 'j')Left 'J'
>>>bimap toUpper (+1) (Right 3)Right 4
Instances
| Bifunctor Either | Since: base-4.8.0.0 |
| Bifunctor (,) | Since: base-4.8.0.0 |
| Bifunctor Arg | Since: base-4.9.0.0 |
| Bifunctor Of | |
| Bifunctor ((,,) x1) | Since: base-4.8.0.0 |
| Bifunctor (Const :: Type -> Type -> Type) | Since: base-4.8.0.0 |
| Bifunctor (K1 i :: Type -> Type -> Type) | Since: base-4.9.0.0 |
| Bifunctor ((,,,) x1 x2) | Since: base-4.8.0.0 |
| Bifunctor ((,,,,) x1 x2 x3) | Since: base-4.8.0.0 |
| Bifunctor ((,,,,,) x1 x2 x3 x4) | Since: base-4.8.0.0 |
| Bifunctor ((,,,,,,) x1 x2 x3 x4 x5) | Since: base-4.8.0.0 |
class Monad m => MonadIO (m :: Type -> Type) where #
Monads in which IO computations may be embedded.
Any monad built by applying a sequence of monad transformers to the
IO monad will be an instance of this class.
Instances should satisfy the following laws, which state that liftIO
is a transformer of monads:
Instances
Identity functor and monad. (a non-strict monad)
Since: base-4.8.0.0
Constructors
| Identity | |
Fields
| |
Instances
void :: Functor f => f a -> f () #
void valueIO action.
Examples
Replace the contents of a Maybe Int
>>>void NothingNothing>>>void (Just 3)Just ()
Replace the contents of an Either Int IntEither Int ()
>>>void (Left 8675309)Left 8675309>>>void (Right 8675309)Right ()
Replace every element of a list with unit:
>>>void [1,2,3][(),(),()]
Replace the second element of a pair with unit:
>>>void (1,2)(1,())
Discard the result of an IO action:
>>>mapM print [1,2]1 2 [(),()]>>>void $ mapM print [1,2]1 2
liftM2 :: Monad m => (a1 -> a2 -> r) -> m a1 -> m a2 -> m r #
Promote a function to a monad, scanning the monadic arguments from left to right. For example,
liftM2 (+) [0,1] [0,2] = [0,2,1,3] liftM2 (+) (Just 1) Nothing = Nothing
liftA3 :: Applicative f => (a -> b -> c -> d) -> f a -> f b -> f c -> f d #
Lift a ternary function to actions.
class MFunctor (t :: (Type -> Type) -> k -> Type) where #
A functor in the category of monads, using hoist as the analog of fmap:
hoist (f . g) = hoist f . hoist g hoist id = id
Methods
hoist :: forall m n (b :: k). Monad m => (forall a. m a -> n a) -> t m b -> t n b #
Lift a monad morphism from m to n into a monad morphism from
(t m) to (t n)
The first argument to hoist must be a monad morphism, even though the
type system does not enforce this
Instances
class (MFunctor t, MonadTrans t) => MMonad (t :: (Type -> Type) -> Type -> Type) where #
A monad in the category of monads, using lift from MonadTrans as the
analog of return and embed as the analog of (=<<):
embed lift = id embed f (lift m) = f m embed g (embed f t) = embed (\m -> embed g (f m)) t
Methods
embed :: forall (n :: Type -> Type) m b. Monad n => (forall a. m a -> t n a) -> t m b -> t n b #
class MonadTrans (t :: (Type -> Type) -> Type -> Type) where #
The class of monad transformers. Instances should satisfy the
following laws, which state that lift is a monad transformation:
Methods
lift :: Monad m => m a -> t m a #
Lift a computation from the argument monad to the constructed monad.
Instances
mapped :: (Monad m, Functor f) => (forall x. f x -> m (g x)) -> Stream f m r -> Stream g m r #
Map layers of one functor to another with a transformation involving the base monad. This could be trivial, e.g.
let noteBeginning text x = putStrLn text >> return text
this is completely functor-general
maps and mapped obey these rules:
maps id = id mapped return = id maps f . maps g = maps (f . g) mapped f . mapped g = mapped (f <=< g) maps f . mapped g = mapped (fmap f . g) mapped f . maps g = mapped (f <=< fmap g)
maps is more fundamental than mapped, which is best understood as a convenience
for effecting this frequent composition:
mapped phi = decompose . maps (Compose . phi)
Note that lazily, strictly, fst', and mapOf are all so-called natural transformations on the primitive Of a functor.
If we write
type f ~~> g = forall x . f x -> g x
then we can restate some types as follows:
mapOf :: (a -> b) -> Of a ~~> Of b -- Bifunctor first lazily :: Of a ~~> (,) a Identity . fst' :: Of a ~~> Identity a
Manipulation of a Stream f m r by mapping often turns on recognizing natural transformations of f.
Thus maps is far more general the the map of the Streaming.Prelude, which can be
defined thus:
S.map :: (a -> b) -> Stream (Of a) m r -> Stream (Of b) m r S.map f = maps (mapOf f)
i.e.
S.map f = maps (\(a :> x) -> (f a :> x))
This rests on recognizing that mapOf is a natural transformation; note though
that it results in such a transformation as well:
S.map :: (a -> b) -> Stream (Of a) m ~~> Stream (Of b) m
Thus we can maps it in turn.
cutoff :: forall (m :: Type -> Type) (f :: Type -> Type) r. (Monad m, Functor f) => Int -> Stream f m r -> Stream f m (Maybe r) #
untilJust :: forall m (f :: Type -> Type) r. (Monad m, Applicative f) => m (Maybe r) -> Stream f m r #
Repeat a
delays :: forall (m :: Type -> Type) (f :: Type -> Type) r. (MonadIO m, Applicative f) => Double -> Stream f m r #
never :: forall (m :: Type -> Type) (f :: Type -> Type) r. (Monad m, Applicative f) => Stream f m r #
never interleaves the pure applicative action with the return of the monad forever.
It is the empty of the Alternative instance, thus
never <|> a = a a <|> never = a
and so on. If w is a monoid then never :: Stream (Of w) m r is
the infinite sequence of mempty, and
str1 <|> str2 appends the elements monoidally until one of streams ends.
Thus we have, e.g.
>>>S.stdoutLn $ S.take 2 $ S.stdinLn <|> S.repeat " " <|> S.stdinLn <|> S.repeat " " <|> S.stdinLn1<Enter> 2<Enter> 3<Enter> 1 2 3 4<Enter> 5<Enter> 6<Enter> 4 5 6
This is equivalent to
>>>S.stdoutLn $ S.take 2 $ foldr (<|>) never [S.stdinLn, S.repeat " ", S.stdinLn, S.repeat " ", S.stdinLn ]
Where f is a monad, (<|>) sequences the conjoined streams stepwise. See the
definition of paste here,
where the separate steps are bytestreams corresponding to the lines of a file.
Given, say,
data Branch r = Branch r r deriving Functor -- add obvious applicative instance
then never :: Stream Branch Identity r is the pure infinite binary tree with
(inaccessible) rs in its leaves. Given two binary trees, tree1 <|> tree2
intersects them, preserving the leaves that came first,
so tree1 <|> never = tree1
Stream Identity m r is an action in m that is indefinitely delayed. Such an
action can be constructed with e.g. untilJust.
untilJust :: (Monad m, Applicative f) => m (Maybe r) -> Stream f m r
Given two such items, <|> instance races them.
It is thus the iterative monad transformer specially defined in
Control.Monad.Trans.Iter
So, for example, we might write
>>>let justFour str = if length str == 4 then Just str else Nothing>>>let four = untilJust (fmap justFour getLine)>>>run fourone<Enter> two<Enter> three<Enter> four<Enter> "four"
The Alternative instance in
Control.Monad.Trans.Free
is avowedly wrong, though no explanation is given for this.
groups :: forall (m :: Type -> Type) (f :: Type -> Type) (g :: Type -> Type) r. (Monad m, Functor f, Functor g) => Stream (Sum f g) m r -> Stream (Sum (Stream f m) (Stream g m)) m r #
Group layers in an alternating stream into adjoining sub-streams of one type or another.
unzips :: forall (m :: Type -> Type) (f :: Type -> Type) (g :: Type -> Type) r. (Monad m, Functor f, Functor g) => Stream (Compose f g) m r -> Stream f (Stream g m) r #
expandPost :: forall (m :: Type -> Type) g f h r. (Monad m, Functor g) => (forall a b. (g a -> b) -> f a -> h b) -> Stream f m r -> Stream g (Stream h m) r #
If Of had a Comonad instance, then we'd have
copy = expandPost extend
See expand for a version that requires a Functor f instance
instead.
expand :: forall (m :: Type -> Type) f g h r. (Monad m, Functor f) => (forall a b. (g a -> b) -> f a -> h b) -> Stream f m r -> Stream g (Stream h m) r #
If Of had a Comonad instance, then we'd have
copy = expand extend
See expandPost for a version that requires a Functor g
instance instead.
unseparate :: forall (m :: Type -> Type) (f :: Type -> Type) (g :: Type -> Type) r. (Monad m, Functor f, Functor g) => Stream f (Stream g m) r -> Stream (Sum f g) m r #
separate :: forall (m :: Type -> Type) (f :: Type -> Type) (g :: Type -> Type) r. (Monad m, Functor f, Functor g) => Stream (Sum f g) m r -> Stream f (Stream g m) r #
Given a stream on a sum of functors, make it a stream on the left functor,
with the streaming on the other functor as the governing monad. This is
useful for acting on one or the other functor with a fold, leaving the
other material for another treatment. It generalizes
partitionEithers, but actually streams properly.
>>>let odd_even = S.maps (S.distinguish even) $ S.each [1..10::Int]>>>:t separate odd_evenseparate odd_even :: Monad m => Stream (Of Int) (Stream (Of Int) m) ()
Now, for example, it is convenient to fold on the left and right values separately:
>>>S.toList $ S.toList $ separate odd_even[2,4,6,8,10] :> ([1,3,5,7,9] :> ())
Or we can write them to separate files or whatever:
>>>S.writeFile "even.txt" . S.show $ S.writeFile "odd.txt" . S.show $ S.separate odd_even>>>:! cat even.txt2 4 6 8 10>>>:! cat odd.txt1 3 5 7 9
Of course, in the special case of Stream (Of a) m r, we can achieve the above
effects more simply by using copy
>>>S.toList . S.filter even $ S.toList . S.filter odd $ S.copy $ each [1..10::Int][2,4,6,8,10] :> ([1,3,5,7,9] :> ())
But separate and unseparate are functor-general.
interleaves :: forall (m :: Type -> Type) (h :: Type -> Type) r. (Monad m, Applicative h) => Stream h m r -> Stream h m r -> Stream h m r #
Interleave functor layers, with the effects of the first preceding the effects of the second. When the first stream runs out, any remaining effects in the second are ignored.
interleaves = zipsWith (liftA2 (,))
>>>let paste = \a b -> interleaves (Q.lines a) (maps (Q.cons' '\t') (Q.lines b))>>>Q.stdout $ Q.unlines $ paste "hello\nworld\n" "goodbye\nworld\n"hello goodbye world world
zips :: forall (m :: Type -> Type) (f :: Type -> Type) (g :: Type -> Type) r. (Monad m, Functor f, Functor g) => Stream f m r -> Stream g m r -> Stream (Compose f g) m r #
zipsWith' :: forall f g h (m :: Type -> Type) r. Monad m => (forall x y p. (x -> y -> p) -> f x -> g y -> h p) -> Stream f m r -> Stream g m r -> Stream h m r #
Zip two streams together.
zipsWith :: forall f g h (m :: Type -> Type) r. (Monad m, Functor h) => (forall x y. f x -> g y -> h (x, y)) -> Stream f m r -> Stream g m r -> Stream h m r #
Zip two streams together. The zipsWith' function should generally
be preferred for efficiency.
yields :: forall (m :: Type -> Type) f r. (Monad m, Functor f) => f r -> Stream f m r #
yields is like lift for items in the streamed functor.
It makes a singleton or one-layer succession.
lift :: (Monad m, Functor f) => m r -> Stream f m r yields :: (Monad m, Functor f) => f r -> Stream f m r
Viewed in another light, it is like a functor-general version of yield:
S.yield a = yields (a :> ())
effect :: forall m (f :: Type -> Type) r. (Monad m, Functor f) => m (Stream f m r) -> Stream f m r #
Wrap an effect that returns a stream
effect = join . lift
wrap :: forall (m :: Type -> Type) f r. (Monad m, Functor f) => f (Stream f m r) -> Stream f m r #
Wrap a new layer of a stream. So, e.g.
S.cons :: Monad m => a -> Stream (Of a) m r -> Stream (Of a) m r S.cons a str = wrap (a :> str)
and, recursively:
S.each :: (Monad m, Foldable t) => t a -> Stream (Of a) m () S.each = foldr (\a b -> wrap (a :> b)) (return ())
The two operations
wrap :: (Monad m, Functor f ) => f (Stream f m r) -> Stream f m r effect :: (Monad m, Functor f ) => m (Stream f m r) -> Stream f m r
are fundamental. We can define the parallel operations yields and lift in
terms of them
yields :: (Monad m, Functor f ) => f r -> Stream f m r yields = wrap . fmap return lift :: (Monad m, Functor f ) => m r -> Stream f m r lift = effect . fmap return
hoistUnexposed :: forall m (f :: Type -> Type) n r. (Monad m, Functor f) => (forall a. m a -> n a) -> Stream f m r -> Stream f n r #
A less-efficient version of hoist that works properly even when its
argument is not a monad morphism.
hoistUnexposed = hoist . unexposed
replicates :: forall (m :: Type -> Type) f. (Monad m, Functor f) => Int -> f () -> Stream f m () #
Repeat a functorial layer, command or instruction a fixed number of times.
replicates n = takes n . repeats
repeatsM :: (Monad m, Functor f) => m (f ()) -> Stream f m r #
Repeat an effect containing a functorial layer, command or instruction forever.
repeats :: forall (m :: Type -> Type) f r. (Monad m, Functor f) => f () -> Stream f m r #
Repeat a functorial layer (a "command" or "instruction") forever.
distribute :: forall (m :: Type -> Type) (f :: Type -> Type) t r. (Monad m, Functor f, MonadTrans t, MFunctor t, Monad (t (Stream f m))) => Stream f (t m) r -> t (Stream f m) r #
Make it possible to 'run' the underlying transformed monad.
chunksOf :: forall (m :: Type -> Type) (f :: Type -> Type) r. (Monad m, Functor f) => Int -> Stream f m r -> Stream (Stream f m) m r #
Break a stream into substreams each with n functorial layers.
>>>S.print $ mapped S.sum $ chunksOf 2 $ each [1,1,1,1,1]2 2 1
takes :: forall (m :: Type -> Type) (f :: Type -> Type) r. (Monad m, Functor f) => Int -> Stream f m r -> Stream f m () #
splitsAt :: forall (m :: Type -> Type) (f :: Type -> Type) r. (Monad m, Functor f) => Int -> Stream f m r -> Stream f m (Stream f m r) #
Split a succession of layers after some number, returning a streaming or effectful pair.
>>>rest <- S.print $ S.splitAt 1 $ each [1..3]1>>>S.print rest2 3
splitAt 0 = return splitAt n >=> splitAt m = splitAt (m+n)
Thus, e.g.
>>>rest <- S.print $ splitsAt 2 >=> splitsAt 2 $ each [1..5]1 2 3 4>>>S.print rest5
concats :: forall (m :: Type -> Type) (f :: Type -> Type) r. (Monad m, Functor f) => Stream (Stream f m) m r -> Stream f m r #
Dissolves the segmentation into layers of Stream f m layers.
iterT :: (Functor f, Monad m) => (f (m a) -> m a) -> Stream f m a -> m a #
Specialized fold following the usage of Control.Monad.Trans.Free
iterT alg = streamFold return join alg iterT alg = runIdentityT . iterTM (IdentityT . alg . fmap runIdentityT)
iterTM :: forall f (m :: Type -> Type) t a. (Functor f, Monad m, MonadTrans t, Monad (t m)) => (f (t m a) -> t m a) -> Stream f m a -> t m a #
Specialized fold following the usage of Control.Monad.Trans.Free
iterTM alg = streamFold return (join . lift) iterTM alg = iterT alg . hoist lift
intercalates :: forall (m :: Type -> Type) t x r. (Monad m, Monad (t m), MonadTrans t) => t m x -> Stream (t m) m r -> t m r #
Interpolate a layer at each segment. This specializes to e.g.
intercalates :: (Monad m, Functor f) => Stream f m () -> Stream (Stream f m) m r -> Stream f m r
mapsM_ :: (Functor f, Monad m) => (forall x. f x -> m x) -> Stream f m r -> m r #
Map each layer to an effect, and run them all.
decompose :: forall (m :: Type -> Type) (f :: Type -> Type) r. (Monad m, Functor f) => Stream (Compose m f) m r -> Stream f m r #
Rearrange a succession of layers of the form Compose m (f x).
we could as well define decompose by mapsM:
decompose = mapped getCompose
but mapped is best understood as:
mapped phi = decompose . maps (Compose . phi)
since maps and hoist are the really fundamental operations that preserve the
shape of the stream:
maps :: (Monad m, Functor f) => (forall x. f x -> g x) -> Stream f m r -> Stream g m r hoist :: (Monad m, Functor f) => (forall a. m a -> n a) -> Stream f m r -> Stream f n r
mapsMPost :: forall m f g r. (Monad m, Functor g) => (forall x. f x -> m (g x)) -> Stream f m r -> Stream g m r #
Map layers of one functor to another with a transformation involving the base monad.
mapsMPost is essentially the same as mapsM, but it imposes a Functor constraint on
its target functor rather than its source functor. It should be preferred if fmap
is cheaper for the target functor than for the source functor.
mapsPost is more fundamental than mapsMPost, which is best understood as a convenience
for effecting this frequent composition:
mapsMPost phi = decompose . mapsPost (Compose . phi)
The streaming prelude exports the same function under the better name mappedPost,
which overlaps with the lens libraries.
mapsPost :: forall (m :: Type -> Type) f g r. (Monad m, Functor g) => (forall x. f x -> g x) -> Stream f m r -> Stream g m r #
Map layers of one functor to another with a transformation. Compare
hoist, which has a similar effect on the monadic parameter.
mapsPost id = id mapsPost f . mapsPost g = mapsPost (f . g) mapsPost f = maps f
mapsPost is essentially the same as maps, but it imposes a Functor constraint on
its target functor rather than its source functor. It should be preferred if fmap
is cheaper for the target functor than for the source functor.
mapsM :: (Monad m, Functor f) => (forall x. f x -> m (g x)) -> Stream f m r -> Stream g m r #
Map layers of one functor to another with a transformation involving the base monad.
maps is more fundamental than mapsM, which is best understood as a convenience
for effecting this frequent composition:
mapsM phi = decompose . maps (Compose . phi)
The streaming prelude exports the same function under the better name mapped,
which overlaps with the lens libraries.
maps :: forall (m :: Type -> Type) f g r. (Monad m, Functor f) => (forall x. f x -> g x) -> Stream f m r -> Stream g m r #
Map layers of one functor to another with a transformation. Compare
hoist, which has a similar effect on the monadic parameter.
maps id = id maps f . maps g = maps (f . g)
unfold :: (Monad m, Functor f) => (s -> m (Either r (f s))) -> s -> Stream f m r #
Build a Stream by unfolding steps starting from a seed. See also
the specialized unfoldr in the prelude.
unfold inspect = id -- modulo the quotient we work with unfold Pipes.next :: Monad m => Producer a m r -> Stream ((,) a) m r unfold (curry (:>) . Pipes.next) :: Monad m => Producer a m r -> Stream (Of a) m r
inspect :: Monad m => Stream f m r -> m (Either r (f (Stream f m r))) #
Inspect the first stage of a freely layered sequence.
Compare Pipes.next and the replica Streaming.Prelude.next.
This is the uncons for the general unfold.
unfold inspect = id Streaming.Prelude.unfoldr StreamingPrelude.next = id
streamBuild :: (forall b. (r -> b) -> (m b -> b) -> (f b -> b) -> b) -> Stream f m r #
Reflect a church-encoded stream; cp. GHC.Exts.build
streamFold return_ effect_ step_ (streamBuild psi) = psi return_ effect_ step_
streamFold :: (Functor f, Monad m) => (r -> b) -> (m b -> b) -> (f b -> b) -> Stream f m r -> b #
streamFold reorders the arguments of destroy to be more akin
to foldr It is more convenient to query in ghci to figure out
what kind of 'algebra' you need to write.
>>>:t streamFold return join(Monad m, Functor f) => (f (m a) -> m a) -> Stream f m a -> m a -- iterT
>>>:t streamFold return (join . lift)(Monad m, Monad (t m), Functor f, MonadTrans t) => (f (t m a) -> t m a) -> Stream f m a -> t m a -- iterTM
>>>:t streamFold return effect(Monad m, Functor f, Functor g) => (f (Stream g m r) -> Stream g m r) -> Stream f m r -> Stream g m r
>>>:t \f -> streamFold return effect (wrap . f)(Monad m, Functor f, Functor g) => (f (Stream g m a) -> g (Stream g m a)) -> Stream f m a -> Stream g m a -- maps
>>>:t \f -> streamFold return effect (effect . fmap wrap . f)(Monad m, Functor f, Functor g) => (f (Stream g m a) -> m (g (Stream g m a))) -> Stream f m a -> Stream g m a -- mapped
streamFold done eff construct
= eff . iterT (return . construct . fmap eff) . fmap done
destroy :: (Functor f, Monad m) => Stream f m r -> (f b -> b) -> (m b -> b) -> (r -> b) -> b #
Map a stream to its church encoding; compare Data.List.foldr.
destroyExposed may be more efficient in some cases when
applicable, but it is less safe.
destroy s construct eff done
= eff . iterT (return . construct . fmap eff) . fmap done $ s
data Stream (f :: Type -> Type) (m :: Type -> Type) r #
Instances
| (Functor f, MonadState s m) => MonadState s (Stream f m) | |
| (Functor f, MonadReader r m) => MonadReader r (Stream f m) | |
| (Functor f, MonadError e m) => MonadError e (Stream f m) | |
Defined in Streaming.Internal Methods throwError :: e -> Stream f m a # catchError :: Stream f m a -> (e -> Stream f m a) -> Stream f m a # | |
| Functor f => MMonad (Stream f) | |
| Functor f => MonadTrans (Stream f) | |
Defined in Streaming.Internal | |
| Functor f => MFunctor (Stream f :: (Type -> Type) -> Type -> Type) | |
| (Functor f, Monad m) => Monad (Stream f m) | |
| (Functor f, Monad m) => Functor (Stream f m) | Operates covariantly on the stream result, not on its elements: Stream (Of a) m r
^ ^
| `--- This is what |
| (Functor f, MonadFail m) => MonadFail (Stream f m) | |
Defined in Streaming.Internal | |
| (Functor f, Monad m) => Applicative (Stream f m) | |
Defined in Streaming.Internal | |
| (Applicative f, Monad m) => Alternative (Stream f m) | The empty = never (<|>) = zipsWith (liftA2 (,)) |
| (Applicative f, Monad m) => MonadPlus (Stream f m) | |
| (Monad m, Functor f, Eq1 m, Eq1 f) => Eq1 (Stream f m) | |
| (Monad m, Functor f, Ord1 m, Ord1 f) => Ord1 (Stream f m) | |
Defined in Streaming.Internal | |
| (Monad m, Functor f, Show (m ShowSWrapper), Show (f ShowSWrapper)) => Show1 (Stream f m) | |
| (MonadIO m, Functor f) => MonadIO (Stream f m) | |
Defined in Streaming.Internal | |
| (Functor f, PrimMonad m) => PrimMonad (Stream f m) Source # | |
| (Monad m, Eq (m (Either r (f (Stream f m r))))) => Eq (Stream f m r) | |
| (Monad m, Ord (m (Either r (f (Stream f m r))))) => Ord (Stream f m r) | |
Defined in Streaming.Internal | |
| (Monad m, Show r, Show (m ShowSWrapper), Show (f (Stream f m r))) => Show (Stream f m r) | |
| (Functor f, Monad m, Semigroup w) => Semigroup (Stream f m w) | |
| (Functor f, Monad m, Monoid w) => Monoid (Stream f m w) | |
| type PrimState (Stream f m) Source # | |
Defined in Bio.Streaming | |
A left-strict pair; the base functor for streams of individual elements.
Constructors
| !a :> b infixr 5 |
Instances
| Bifunctor Of | |
| Eq2 Of | |
| Ord2 Of | |
Defined in Data.Functor.Of | |
| Show2 Of | |
| Monoid a => Monad (Of a) | |
| Functor (Of a) | |
| Monoid a => Applicative (Of a) | |
| Foldable (Of a) | |
Defined in Data.Functor.Of Methods fold :: Monoid m => Of a m -> m # foldMap :: Monoid m => (a0 -> m) -> Of a a0 -> m # foldMap' :: Monoid m => (a0 -> m) -> Of a a0 -> m # foldr :: (a0 -> b -> b) -> b -> Of a a0 -> b # foldr' :: (a0 -> b -> b) -> b -> Of a a0 -> b # foldl :: (b -> a0 -> b) -> b -> Of a a0 -> b # foldl' :: (b -> a0 -> b) -> b -> Of a a0 -> b # foldr1 :: (a0 -> a0 -> a0) -> Of a a0 -> a0 # foldl1 :: (a0 -> a0 -> a0) -> Of a a0 -> a0 # elem :: Eq a0 => a0 -> Of a a0 -> Bool # maximum :: Ord a0 => Of a a0 -> a0 # minimum :: Ord a0 => Of a a0 -> a0 # | |
| Traversable (Of a) | |
| Eq a => Eq1 (Of a) | |
| Ord a => Ord1 (Of a) | |
Defined in Data.Functor.Of | |
| Show a => Show1 (Of a) | |
| Generic1 (Of a :: Type -> Type) | |
| (Eq a, Eq b) => Eq (Of a b) | |
| (Data a, Data b) => Data (Of a b) | |
Defined in Data.Functor.Of Methods gfoldl :: (forall d b0. Data d => c (d -> b0) -> d -> c b0) -> (forall g. g -> c g) -> Of a b -> c (Of a b) # gunfold :: (forall b0 r. Data b0 => c (b0 -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Of a b) # toConstr :: Of a b -> Constr # dataTypeOf :: Of a b -> DataType # dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c (Of a b)) # dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Of a b)) # gmapT :: (forall b0. Data b0 => b0 -> b0) -> Of a b -> Of a b # gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Of a b -> r # gmapQr :: forall r r'. (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Of a b -> r # gmapQ :: (forall d. Data d => d -> u) -> Of a b -> [u] # gmapQi :: Int -> (forall d. Data d => d -> u) -> Of a b -> u # gmapM :: Monad m => (forall d. Data d => d -> m d) -> Of a b -> m (Of a b) # gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Of a b -> m (Of a b) # gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Of a b -> m (Of a b) # | |
| (Ord a, Ord b) => Ord (Of a b) | |
| (Read a, Read b) => Read (Of a b) | |
| (Show a, Show b) => Show (Of a b) | |
| Generic (Of a b) | |
| (Semigroup a, Semigroup b) => Semigroup (Of a b) | |
| (Monoid a, Monoid b) => Monoid (Of a b) | |
| type Rep1 (Of a :: Type -> Type) | |
Defined in Data.Functor.Of type Rep1 (Of a :: Type -> Type) = D1 ('MetaData "Of" "Data.Functor.Of" "streaming-0.2.3.0-5bb4c386c52722fe2adff463f2300feb77377c3ffc197c80b0b73327682428a0" 'False) (C1 ('MetaCons ":>" ('InfixI 'RightAssociative 5) 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 a) :*: S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) Par1)) | |
| type Rep (Of a b) | |
Defined in Data.Functor.Of type Rep (Of a b) = D1 ('MetaData "Of" "Data.Functor.Of" "streaming-0.2.3.0-5bb4c386c52722fe2adff463f2300feb77377c3ffc197c80b0b73327682428a0" 'False) (C1 ('MetaCons ":>" ('InfixI 'RightAssociative 5) 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 a) :*: S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 b))) | |
each :: forall (m :: Type -> Type) f a. (Monad m, Foldable f) => f a -> Stream (Of a) m () #
Stream the elements of a pure, foldable container.
>>>S.print $ each [1..3]1 2 3