Data.MSF.Switch

Switching Combinators

Switches allow us to dynamically change the structure
(wiring) of a running network of stream functions.
Semantically, the react on discrete events, but
some of the switching primitives in this module use
the `Either` data type if it allows us to more exactly
describe the semantics of a switch.

Definitions

switchE : MSF m i (Either e o) -> (e -> MSF m i o) -> MSF m i o

  Produces output of the first MSF until it produces
  a `Left`, in which case the event will be used to
  create a new MSF, which will be immediately evaluated
  and used henceforth.
  
  This is a one-time switch, which is often used to
  run an MSF a fixed number of times or until a certain
  event occurs, after which the replacement will be used.
  
  Note: It is unsafe to use this in a recursive setting,
        as it would allow us to create an infinite loop
        of streaming functions, all of which return `Left`s
        forever. Luckily, the totality checker will prevent us
        from doing this.

Totality: total
Visibility: export

switch : MSF m i (HList [o, Event e]) -> (e -> MSF m i o) -> MSF m i o

  Produces output of the given MSF until it fires an event,
  in which case a new MSF is created,
  which will be evaluated immediately and used henceforth.
  
  This uses `switchE` internally, so all restrictions mentioned
  there apply.

Totality: total
Visibility: export

dSwitch : MSF m i (HList [o, Event e]) -> (e -> MSF m i o) -> MSF m i o

  Produces output of the given MSF until it fires an event,
  in which case a new MSF is created,
  which will be used in all further evaluation steps.

Totality: total
Visibility: export

rSwitch : Monad m => MSF m i o -> MSF m (HList [Event (MSF m i o), i]) o

Totality: total
Visibility: export

drSwitch : Monad m => MSF m i o -> MSF m (HList [Event (MSF m i o), i]) o

Totality: total
Visibility: export

drswitchWhen : Monad m => MSF m i o -> MSF m i (Event e) -> (e -> MSF m i o) -> MSF m i o

  Produces output of the first MSF until the second
  fires an event, in which case a new MSF is created,
  which will be used in all futre evaluation cycles.

Totality: total
Visibility: export