acme-missiles 0.2.1 → 0.3

raw patch · 3 files changed

+60/−56 lines, 3 filesPVP ok

version bump matches the API change (PVP)

API changes (from Hackage documentation)

Files

• Acme/Missiles.hs +0/−54
• Acme/Missiles/STM.hs +58/−0
• acme-missiles.cabal +2/−2

@@ -11,62 +11,8 @@  module Acme.Missiles (     launchMissiles,--    -- * Launching missiles in the 'STM' monad-    withMissilesDo,-    launchMissilesSTM, ) where -import Control.Concurrent-import Control.Concurrent.STM-import Control.Exception (bracket)-import Control.Monad (forever)-import System.IO.Unsafe (unsafePerformIO)- -- | Cause serious international side effects. launchMissiles :: IO () launchMissiles = putStrLn "Nuclear launch detected."---- | Perform initialization needed to launch missiles in the 'STM' monad.-withMissilesDo :: IO a -> IO a-withMissilesDo action =-        bracket (forkIO doLaunching)-                killThread-                (\_ -> action)-    where-        doLaunching = forever $ do-            atomically $ do-                n <- readTVar missileCommand-                if n > 0-                    then writeTVar missileCommand (n - 1)-                    else retry-            launchMissiles---- | Launch missiles within an 'STM' computation.  Even if the memory--- transaction is retried, only one salvo of missiles will be launched.------ Example:------ >import Acme.Missiles--- >import Control.Concurrent--- >import Control.Concurrent.STM--- >--- >main :: IO ()--- >main = withMissilesDo $ do--- >    xv <- atomically $ newTVar (2 :: Int)--- >    yv <- atomically $ newTVar (1 :: Int)--- >    atomically $ do--- >        x <- readTVar xv--- >        y <- readTVar yv--- >        if x > y--- >            then launchMissilesSTM--- >            else return ()--- >    threadDelay 100000-launchMissilesSTM :: STM ()-launchMissilesSTM = do-    n <- readTVar missileCommand-    writeTVar missileCommand $! n + 1--missileCommand :: TVar Integer-{-# NOINLINE missileCommand #-}-missileCommand = unsafePerformIO (newTVarIO 0)

@@ -0,0 +1,58 @@+module Acme.Missiles.STM (+    -- * Launching missiles in the 'STM' monad+    withMissilesDo,+    launchMissilesSTM,+) where++import Acme.Missiles (launchMissiles)++import Control.Concurrent       (forkIO, killThread)+import Control.Concurrent.STM   (STM, atomically, retry,+                                 TVar, newTVarIO, readTVar, writeTVar)+import Control.Exception        (bracket)+import Control.Monad            (forever)+import System.IO.Unsafe         (unsafePerformIO)++-- | Perform initialization needed to launch missiles in the 'STM' monad.+withMissilesDo :: IO a -> IO a+withMissilesDo action =+        bracket (forkIO doLaunching)+                killThread+                (\_ -> action)+    where+        doLaunching = forever $ do+            atomically $ do+                n <- readTVar missileCommand+                if n > 0+                    then writeTVar missileCommand (n - 1)+                    else retry+            launchMissiles++-- | Launch missiles within an 'STM' computation.  Even if the memory+-- transaction is retried, only one salvo of missiles will be launched.+--+-- Example:+--+-- >import Acme.Missiles+-- >import Control.Concurrent+-- >import Control.Concurrent.STM+-- >+-- >main :: IO ()+-- >main = withMissilesDo $ do+-- >    xv <- atomically $ newTVar (2 :: Int)+-- >    yv <- atomically $ newTVar (1 :: Int)+-- >    atomically $ do+-- >        x <- readTVar xv+-- >        y <- readTVar yv+-- >        if x > y+-- >            then launchMissilesSTM+-- >            else return ()+-- >    threadDelay 100000+launchMissilesSTM :: STM ()+launchMissilesSTM = do+    n <- readTVar missileCommand+    writeTVar missileCommand $! n + 1++missileCommand :: TVar Integer+{-# NOINLINE missileCommand #-}+missileCommand = unsafePerformIO (newTVarIO 0)

@@ -1,5 +1,5 @@ name:                acme-missiles-version:             0.2.1+version:             0.3 synopsis:            Cause serious international side effects. description:     The highly effectful 'launchMissiles' action, as mentioned in /Beautiful concurrency/,@@ -7,12 +7,12 @@ license:             PublicDomain author:              Joey Adams maintainer:          joeyadams3.14159@gmail.com--- copyright:            category:            Acme build-type:          Simple cabal-version:       >=1.8  library   exposed-modules:     Acme.Missiles+                       Acme.Missiles.STM   build-depends:       base >= 3 && < 5, stm   ghc-options:         -Wall