LogicGrowsOnTrees.Parallel.Purity

This module contains types that represent the purity of a tree, which is either pure, impure, or IO (a special case of impure).

Documentation

data Purity m n where

The purity of a tree, which can be either Pure (for pure trees) or ImpureAtopIO (for impure trees); the latter case is restricted to monads that are instances of MonadIO and for which there exists a way to convert the monad into an IO action.

The two kind arguments, m and n, correspond to respectively the monad in on top of which the TreeT monad transformer is stacked and the monad in which the worker will be run.

Constructors

Pure :: Purity Identity IO

ImpureAtopIO :: MonadIO m => (forall β. m β -> IO β) -> Purity m m

io_purity :: Purity IO IO

The purity of trees in the IO monad.