speculation-0.1.0: speculation.cabal

name:           speculation
version:        0.1.0
license:        BSD3
license-file:   LICENSE
author:         Edward A. Kmett
maintainer:     Edward A. Kmett <ekmett@gmail.com>
stability:      experimental
homepage:       http://github.com/ekmett/speculation
category:       Concurrency
synopsis:       A framework for safe, programmable, speculative parallelism
description:
    A framework for safe, programmable, speculative parallelism, loosely based on
    <http://research.microsoft.com/pubs/118795/pldi026-vaswani.pdf>
    .
    @'spec' g f a@ evaluates @f g@ while forcing @a@, if @g == a@ then @f g@ is returned. Otherwise @f a@ is evaluated.
    .
    Furthermore, if the argument has already been evaluated, we avoid sparking the parallel computation at all.
    .
    If a good guess at the value of @a@ is available, this is one way to induce parallelism in an otherwise sequential task.
    .
    However, if the guess isn\'t available more cheaply than the actual answer, then this saves no work and if the guess is
    wrong, you risk evaluating the function twice.
    .
    > spec a f a = f $! a
    .
    The best-case timeline looks like:
    .
    > [---- f g ----]
    >    [----- a -----]
    > [-- spec g f a --]
    .
    The worst-case timeline looks like:
    .
    > [---- f g ----]
    >    [----- a -----]
    >                  [---- f a ----]
    > [------- spec g f a -----------]
    .
    Compare these to the timeline of @f $! a@:
    .
    > [---- a -----]
    >              [---- f a ----]
    .
    'specSTM' provides a similar time table for STM actions, but also rolls back side-effects.
    .
    /Changes in 0.1.0:/
    .
    * Added @Control.Concurrent.STM.Speculation@ with 'specSTM', and 'specSTM''
    .
    /Changes in 0.0.2:/
    .
    * 'specFoldr1' bug fix
    .
    * Added 'spec'' combinator
    .
    /Changes in 0.0.1:/
    .
    * Added 'WithoutSpeculation' and 'WrappedFoldable'

copyright:      (c) 2010 Edward A. Kmett
build-type:     Simple
cabal-version:  >=1.2
tested-with:    GHC==6.12.1
extra-source-files: README.markdown

library
  ghc-options: -Wall

  build-depends:
    base >= 4 && < 6,
    containers >= 0.2.0.1,
    array >= 0.2 && < 0.4,
    parallel >= 2.2 && < 2.3,
    stm >= 2.1 && < 2.2

  exposed-modules:
    Control.Concurrent.Speculation
    Control.Concurrent.STM.Speculation