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module Control.Distributed.Process.Extras.Internal.Containers.MultiMap

No documentation available.
data MultiMap k v

distributed-process-extras Control.Distributed.Process.Extras.Internal.Containers.MultiMap

Opaque type of MultiMaps.
withLiftMap :: forall (es :: [Effect]) (handlerEs :: [Effect]) (localEs :: [Effect]) r . (HasCallStack, SharedSuffix es handlerEs) => LocalEnv localEs handlerEs -> ((forall a b . () => (Eff es a -> Eff es b) -> Eff localEs a -> Eff localEs b) -> Eff es r) -> Eff es r

effectful-core Effectful.Dispatch.Dynamic

Utility for lifting Eff computations of type
```
Eff es a -> Eff es b
```
to
```
Eff localEs a -> Eff localEs b
```
Note: the computation must not run its argument in a different thread, attempting to do so will result in a runtime error.
withLiftMapIO :: forall (es :: [Effect]) (handlerEs :: [Effect]) (localEs :: [Effect]) r . (HasCallStack, SharedSuffix es handlerEs, IOE :> es) => LocalEnv localEs handlerEs -> ((forall a b . () => (IO a -> IO b) -> Eff localEs a -> Eff localEs b) -> Eff es r) -> Eff es r

effectful-core Effectful.Dispatch.Dynamic

Utility for lifting IO computations of type
```
IO a -> IO b
```
to
```
Eff localEs a -> Eff localEs b
```
Note: the computation must not run its argument in a different thread, attempting to do so will result in a runtime error. Useful e.g. for lifting the unmasking function in mask-like computations:
```
>>> :{
data Fork :: Effect where
ForkWithUnmask :: ((forall a. m a -> m a) -> m ()) -> Fork m ThreadId
type instance DispatchOf Fork = Dynamic
:}
```
```
>>> :{
runFork :: IOE :> es => Eff (Fork : es) a -> Eff es a
runFork = interpret $ \env (ForkWithUnmask m) -> withLiftMapIO env $ \liftMap -> do
localUnliftIO env (ConcUnlift Ephemeral $ Limited 1) $ \unlift -> do
forkIOWithUnmask $ \unmask -> unlift $ m $ liftMap unmask
:}
```
unsafeLiftMapIO :: forall a b (es :: [Effect]) . HasCallStack => (IO a -> IO b) -> Eff es a -> Eff es b

effectful-core Effectful.Dispatch.Static

Utility for lifting IO computations of type
```
IO a -> IO b
```
to
```
Eff es a -> Eff es b
```
Note: the computation must not run its argument in a separate thread, attempting to do so will result in a runtime error. This function is unsafe because it can be used to introduce arbitrary IO actions into pure Eff computations.
reallyUnsafeLiftMapIO :: forall a b (es :: [Effect]) . (IO a -> IO b) -> Eff es a -> Eff es b

effectful-core Effectful.Dispatch.Static.Unsafe

Utility for lifting IO computations of type
```
IO a -> IO b
```
to
```
Eff es a -> Eff es b
```
This function is really unsafe because:
- It can be used to introduce arbitrary IO actions into pure Eff computations.
- The IO computation must run its argument in a way that's perceived as sequential to the outside observer, e.g. in the same thread or in a worker thread that finishes before the argument is run again.
Warning: if you disregard the second point, you will experience weird bugs, data races or internal consistency check failures. When in doubt, use unsafeLiftMapIO, especially since this version saves only a simple safety check per call of reallyUnsafeLiftMapIO f.
reallyUnsafeLiftMapIO :: forall a b (es :: [Effect]) . (IO a -> IO b) -> Eff es a -> Eff es b

effectful-core Effectful.Internal.Monad

Utility for lifting IO computations of type
```
IO a -> IO b
```
to
```
Eff es a -> Eff es b
```
This function is really unsafe because:
- It can be used to introduce arbitrary IO actions into pure Eff computations.
- The IO computation must run its argument in a way that's perceived as sequential to the outside observer, e.g. in the same thread or in a worker thread that finishes before the argument is run again.
Warning: if you disregard the second point, you will experience weird bugs, data races or internal consistency check failures. When in doubt, use unsafeLiftMapIO, especially since this version saves only a simple safety check per call of reallyUnsafeLiftMapIO f.

distributed-process-extras	Control.Distributed.Process.Extras.Internal.Containers.MultiMap

effectful-core	Effectful.Dispatch.Dynamic

effectful-core	Effectful.Dispatch.Dynamic

effectful-core	Effectful.Dispatch.Static

effectful-core	Effectful.Dispatch.Static.Unsafe

effectful-core	Effectful.Internal.Monad

bimap :: Bifunctor p => (a -> b) -> (c -> d) -> p a c -> p b d

foundation	Foundation

Map over both arguments at the same time.

bimap f g ≡ first f . second g

Examples

>>> bimap toUpper (+1) ('j', 3)
('J',4)

>>> bimap toUpper (+1) (Left 'j')
Left 'J'

>>> bimap toUpper (+1) (Right 3)
Right 4

fmap :: Functor f => (a -> b) -> f a -> f b

foundation Foundation

fmap is used to apply a function of type (a -> b) to a value of type f a, where f is a functor, to produce a value of type f b. Note that for any type constructor with more than one parameter (e.g., Either), only the last type parameter can be modified with fmap (e.g., b in `Either a b`). Some type constructors with two parameters or more have a Bifunctor instance that allows both the last and the penultimate parameters to be mapped over.
Examples
Convert from a Maybe Int to a Maybe String using show:
```
>>> fmap show Nothing
Nothing

>>> fmap show (Just 3)
Just "3"
```
Convert from an Either Int Int to an Either Int String using show:
```
>>> fmap show (Left 17)
Left 17

>>> fmap show (Right 17)
Right "17"
```
Double each element of a list:
```
>>> fmap (*2) [1,2,3]
[2,4,6]
```
Apply even to the second element of a pair:
```
>>> fmap even (2,2)
(2,True)
```
It may seem surprising that the function is only applied to the last element of the tuple compared to the list example above which applies it to every element in the list. To understand, remember that tuples are type constructors with multiple type parameters: a tuple of 3 elements (a,b,c) can also be written (,,) a b c and its Functor instance is defined for Functor ((,,) a b) (i.e., only the third parameter is free to be mapped over with fmap). It explains why fmap can be used with tuples containing values of different types as in the following example:
```
>>> fmap even ("hello", 1.0, 4)
("hello",1.0,True)
```
data Bitmap

foundation Foundation.Array

No documentation available.

foundation	Foundation.Array

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