Safe Haskell | Safe-Infered |
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The MonadTask class that defines the set of combinators to work with Task monad.

The operations for MonadTask are similar to those of co-routines, with the addition of watching and signaling events.

We also define a set of auto lifting for common transformers. Note that we
purposely leave a case undefined where a state transformer goes on top of
a task monad, because such an operation is either unsound or has to roll
back the state (see

). So it's
recommended to keep TaskT on top of all StateT in a transformer stack.
`liftCallCC`

# MonadTask class

class Monad m => MonadTask e m | m -> e whereSource

`MonadTask`

specifies a task monad `m`

over an event type `e`

.

`yield`

temporarily suspends current task to let others run.

`fork`

spawns a task and runs it immediate until it ends or
suspends before returning to current task.

watch :: (e -> Maybe a) -> m aSource

`watch`

suspends current task to wait for future events, and will
resume execution when an event triggers its watching function.

`signal`

broadcasts an event to all other tasks that are watching,
and give those who wake up the priority to run.

`exit`

ends all tasks and return immediately.

(Monad m, MonadTask a m) => MonadTask a (MaybeT m) | |

(Monad m, MonadTask a m) => MonadTask a (ListT m) | |

(Monad m, MonadTask a m) => MonadTask a (IdentityT m) | |

(Monoid w, Monad m, MonadTask a m) => MonadTask a (WriterT w m) | |

(Monoid w, Monad m, MonadTask a m) => MonadTask a (WriterT w m) | |

(Monad m, MonadTask a m) => MonadTask a (ReaderT r m) | |

(Error e, Monad m, MonadTask a m) => MonadTask a (ErrorT e m) | |

Monad m => MonadTask e (TaskT e m) |