Control.Concurrent.Speculation

Documentation

spec :: Eq a => a -> (a -> b) -> a -> b

Evaluate a function using a cheap guess at the argument in parallel with forcing the argument.

This is one way to induce parallelism in an otherwise sequential task. If the argument has already been evaluated, we avoid sparking the parallel computation.

evaluated :: a -> Bool

Returns a guess as to whether or not a value has been evaluated. This is an impure function that relies on GHC internals and will return false negatives, but (hopefully) no false positives.

specFoldr :: (Speculative f, Eq b) => (Int -> b) -> (a -> b -> b) -> b -> f a -> b

specFoldl :: (Speculative f, Eq b) => (Int -> b) -> (b -> a -> b) -> b -> f a -> b

class Foldable f => Speculative f where

Methods

specFoldr1 :: Eq a => (Int -> a) -> (a -> a -> a) -> f a -> a

Compute a right biased fold. the estimator function is a guess at the value of the suffix

specFoldrN :: Eq b => Int -> (Int -> b) -> (a -> b -> b) -> b -> f a -> b

specFoldl1 :: Eq a => (Int -> a) -> (a -> a -> a) -> f a -> a

Compute a left biased fold. the estimator function is a guess at the value of the prefix

specFoldlN :: Eq b => Int -> (Int -> b) -> (b -> a -> b) -> b -> f a -> b

Instances

Speculative []

Speculative Maybe

Speculative IntMap

Speculative Set

Speculative Seq

Ix i => Speculative (Array i)

Speculative (Map a)