Control.CUtils.Deadlock

Automatic deadlock prevention.

Automatic deadlock detection is inefficient, and computations cannot be rolled back or aborted in general.

Instead, we prevent deadlocks before they happen.

Documentation

data Res t u where

The Res arrow.

Computations are built with these constructors (and the arrow interface). The implementation guarantees progress provided: * Pieces of the arrow that hold locks are finitely examinable, * threads are programmed to eventually release a lock they hold, * locks are the only source of deadlock, * and all locks are used only with the Acq and Rel ctors (which acquire and release a lock resp.).

Constructors

Lift :: Kleisli IO t v -> Res v u -> Res t u

Acq :: MVar () -> Res t u -> Res t u

Rel :: MVar () -> Res t u -> Res t u

Fork :: Res t () -> Res t u -> Res t u

Plus :: Res t v -> Res u v -> Res (Either t u) v

Id :: Res t t

Instances

Arrow Res

ArrowChoice Res

Category * Res

run :: Res t u -> t -> IO u

Use this to run computations built in the Res arrow.

lft :: IO a -> Res v u -> Res v u