Box.Emitter

emit

Documentation

newtype Emitter m a

an Emitter "emits" values of type a. A Source & a Producer (of as) are the two other alternative but overloaded metaphors out there.

An Emitter 'reaches into itself' for the value to emit, where itself is an opaque thing from the pov of usage. An Emitter is named for its main action: it emits.

Constructors

Emitter

Fields

• emit :: m (Maybe a)

Instances

Monad m => Monad (Emitter m)

Defined in Box.Emitter

Methods

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

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

return :: a -> Emitter m a

fail :: String -> Emitter m a

Functor m => Functor (Emitter m)

Defined in Box.Emitter

Methods

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

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

Applicative m => Applicative (Emitter m)

Defined in Box.Emitter

Methods

pure :: a -> Emitter m a

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

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

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

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

(Monad m, Alternative m) => Alternative (Emitter m)

Defined in Box.Emitter

Methods

empty :: Emitter m a

(<|>) :: Emitter m a -> Emitter m a -> Emitter m a

some :: Emitter m a -> Emitter m [a]

many :: Emitter m a -> Emitter m [a]

(Alternative m, Monad m) => MonadPlus (Emitter m)

Defined in Box.Emitter

Methods

mzero :: Emitter m a

mplus :: Emitter m a -> Emitter m a -> Emitter m a

(Alternative m, Monad m) => Semigroup (Emitter m a)

Defined in Box.Emitter

Methods

(<>) :: Emitter m a -> Emitter m a -> Emitter m a

sconcat :: NonEmpty (Emitter m a) -> Emitter m a

stimes :: Integral b => b -> Emitter m a -> Emitter m a

(Alternative m, Monad m) => Monoid (Emitter m a)

Defined in Box.Emitter

Methods

mempty :: Emitter m a

mappend :: Emitter m a -> Emitter m a -> Emitter m a

mconcat :: [Emitter m a] -> Emitter m a

liftE :: MonadConc m => Emitter (STM m) a -> Emitter m a

emap :: Monad m => (a -> m (Maybe b)) -> Emitter m a -> Emitter m b

like a monadic mapMaybe. (See witherable)

keeps

Arguments

:: Monad m

=> ((b -> Constant (First b) b) -> a -> Constant (First b) a)

-> Emitter m a

-> Emitter m b

prism handler

eRead :: (Functor m, Read a) => Emitter m Text -> Emitter m (Either Text a)

read parse emitter

eParse :: Functor m => Parser a -> Emitter m Text -> Emitter m (Either Text a)

attoparsec parse emitter