Data commit

Task/Concurrent-computing/Haskell/concurrent-computing-1.hs

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+import Control.Concurrent
+
+main = mapM_ forkIO [process1, process2, process3] where
+  process1 = putStrLn "Enjoy"
+  process2 = putStrLn "Rosetta"
+  process3 = putStrLn "Code"

Task/Concurrent-computing/Haskell/concurrent-computing-2.hs

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+import Control.Concurrent
+import System.Random
+
+concurrent :: IO ()
+concurrent = do
+    var <- newMVar [] -- use an MVar to collect the results of each thread
+    mapM_ (forkIO . task var) ["Enjoy", "Rosetta", "Code"] -- run 3 threads
+    putStrLn "Press Return to show the results." -- while we wait for the user,
+    -- the threads run
+    _ <- getLine
+    takeMVar var >>= mapM_ putStrLn -- read the results and show them on screen
+    where
+        -- "task" is a thread
+        task v s = do
+            randomRIO (1,10) >>= \r -> threadDelay (r * 100000) -- wait a while
+            val <- takeMVar v -- read the MVar and block other threads from reading it
+            -- until we write another value to it
+            putMVar v (s : val) -- append a text string to the MVar and block other
+            -- threads from writing to it unless it is read first

Task/Concurrent-computing/Haskell/concurrent-computing-3.hs

@@ -0,0 +1,4 @@
+procedure main()
+   L:=[ thread write("Enjoy"), thread write("Rosetta"), thread write("Code") ]
+   every wait(!L)
+end