Modulemonad-par-extras-0.3.3Haskell98

Control.Monad.Par.State

This module provides a notion of (Splittable) State that is compatible with any Par monad.

This module provides instances that make StateT-transformed monads into valid Par monads.

1 class

Packagemonad-par-extras-0.3.3
Exports1
LanguageHaskell98
LicenceBSD-3-Clause
SourceState.hs

classclass SplittableState a where

A type in SplittableState is meant to be added to a Par monad using StateT. It works like any other state except at fork points, where the runtime system splits the state using splitState.

Common examples for applications of SplittableState would include (1) routing a splittable random number generator through a parallel computation, and (2) keeping a tree-index that locates the current computation within the binary tree of forks. Also, it is possible to simply duplicate the state at all fork points, enabling "thread local" copies of the state.

The limitation of this approach is that the splitting method is fixed, and the same at all fork points.

Methods

splitState :: a -> (a, a)

Instances2SplittableState

SplittableState PedigreeDefined in monad-par-extras-0.3.3 · Control.Monad.Par.Pedigree
RandomGen g => SplittableState gDefined in monad-par-extras-0.3.3 · Control.Monad.Par.RNG · orphan
Trivial instance.

Orphan instances

4 instances

(SplittableState s, ParFuture fut p) => ParFuture fut (StateT s p)
Adding State to a ParFuture monad yield s another ParFuture monad.
(SplittableState s, ParFuture fut p) => ParFuture fut (StateT s p)
Adding State to a ParFuture monad yields another ParFuture monad.
(SplittableState s, ParIVar iv p) => ParIVar iv (StateT s p)
Likewise, adding State to a ParIVar monad yield s another ParIVar monad.
(SplittableState s, ParIVar iv p) => ParIVar iv (StateT s p)
Likewise, adding State to a ParIVar monad yield s another ParIVar monad.