Data.MSF.Trans

Monad morphisms and interaction with monad transformer stacks.

Definitions

morphGS : Monad m1 => ((i1 -> m1 (o1, c)) -> i2 -> m2 (o2, c)) -> MSF m1 i1 o1 -> MSF m2 i2 o2

  The most general structure-preserving monad morphism.
  This can be used to change the input and output type plus
  the effect type of an MSF without affecting its internal
  structure (wiring of stream functions).
  
  For examples of usage, have a look at the implementations of
  functions like `unreader`, `reader`, `unstate`, and similar.

Visibility: export

morph : Monad m1 => (m1 c -> m2 c) -> MSF m1 i1 o1 -> MSF m2 i1 o1

  Applies a monad morphism to change the context of an MSF.
  
  ```idris example
  fromPure : Monad m => MSF Identity i o -> MSF m i o
  fromPure = morph (pure . runIdentity)
  ```

Visibility: export

fromPure : Monad m => MSF Identity i o -> MSF m i o

  Puts a pure MSF (over the `Identity` monad) in another
  monadic context.

Visibility: export

get : MonadState s m => MSF m i s

  Alias for `constM get`

Visibility: export

put : MonadState s m => MSF m s ()

  Alias for `constM put`

Visibility: export

modify : MonadState s m => MSF m (s -> s) ()

  Alias for `constM modify`

Visibility: export

fromState : Monad m => MSF (StateT s m) i o -> MSF m (HList [s, i]) (HList [s, o])

  Converts an outer `StateT` wrapper to an MSF converting
  an additional argument of the state type.

Visibility: export

loopState : Monad m => s -> MSF (StateT s m) i o -> MSF m i o

  Runs the given stateful MSF as a feedback loop with `ini` as the
  initial input.
  
  This is a shorthand for `feedback ini . fromState`.

Visibility: export

fromState_ : Monad m => MSF (StateT s m) () () -> MSF m s s

  Like `fromState` but drops the uninteresting unit in- and output.

Visibility: export

toState : Monad m => MSF m (HList [s, i]) (HList [s, o]) -> MSF (StateT s m) i o

  Converts a state transforming MSF to one with its monadic context
  wrapped in `StateT s`.

Visibility: export

toState_ : Monad m => MSF m s s -> MSF (StateT s m) () ()

  Like `toState` but for MSFs without additional in- or output

Visibility: export

ask : MonadReader e m => MSF m i e

  Alias for `constM ask`

Visibility: export

fromReader : Monad m => MSF (ReaderT e m) i o -> MSF m (HList [e, i]) o

  Converts an outer `ReaderT` wrapper to an MSF taking an
  an additional input.

Visibility: export

withEnv : Monad m => e -> MSF (ReaderT e m) i o -> MSF m i o

  Converts the given MSF to use `env` as its environment.
  
  This is an alias for `fan [ const env, id ] >>> fromReader sf`.

Visibility: export

fromReader_ : Monad m => MSF (ReaderT e m) () o -> MSF m e o

  Like `unReader` but drops the uninteresting unit input.

Visibility: export

toReader : Monad m => MSF m (HList [e, i]) o -> MSF (ReaderT e m) i o

  Converts an MSF taking an additional input
  to one with its monadic context wrapped in `ReaderT e`.

Visibility: export

toReader_ : Monad m => MSF m e o -> MSF (ReaderT e m) () o

  Like `toReader` but for MSFs without additional input

Visibility: export

tell : MonadWriter w m => MSF m w ()

  Alias for `arrM tell`

Visibility: export

fromWriter : Monoid w => Monad m => MSF (WriterT w m) i o -> MSF m i (HList [w, o])

  Converts an outer `WriterT` wrapper to an MSF producing
  an additional output.

Visibility: export

fromWriter_ : Monoid w => Monad m => MSF (WriterT w m) i () -> MSF m i w

  Like `fromWriter` but ignores the uninteresting output.

Visibility: export

toWriter : Monoid w => Monad m => MSF m i (HList [w, o]) -> MSF (WriterT w m) i o

  Converts an MSF producing an additional output
  to one with its monadic context wrapped in `WriterT w`.

Visibility: export

toWriter_ : Monoid w => Monad m => MSF m i w -> MSF (WriterT w m) i ()

  Like `toWriter` but produces unit as output.

Visibility: export