Merge branch 'master' of github.com:typeclasses/haskell-phrasebook

Author: argumatronic

outputs/threads.txt

@@ -1 +1,10 @@
+main: 1
+main: 2
+main: 3
+...
+...
+...
+...
+...
+...
 done

outputs/transactions.txt

@@ -1,4 +1,8 @@
+...
 Total: 1000
+...
 Total: 1000
+...
 Total: 1000
+...
 Total: 1000

readme.md

@@ -33,7 +33,7 @@ In addition to the code examples themselves, the results from running the exampl
 
 When any source code or dependency versions change, run `./tools/generate-outputs`. This script runs all of the examples and updates the output files.
 
-Only the standard output stream (`stdout`) is captured in the output files. Any examples that include nondeterministic behavior (such as `threads.hs`) print the nondeterministic portion of their output to the standard error stream (`stderr`) to avoid including non-repeatable results in the output files.
+Any examples that include nondeterministic behavior (such as `threads.hs`) have the nondeterministic portion of their output redacted as "..." to avoid including non-repeatable results in the output files.
 
 ## Nix dependency versions
 

threads.hs

@@ -6,15 +6,15 @@ import System.IO
 
 main =
   do
-    hSetBuffering stderr LineBuffering
+    hSetBuffering stdout LineBuffering
 
     tasksCompleted <- atomically (newTVar 0)
 
     let
         task x =
           do
             for_ [1..3] $ \i ->
-                hPutStrLn stderr (x ++ ": " ++ show i)
+                putStrLn (x ++ ": " ++ show i)
             atomically $
                 modifyTVar' tasksCompleted (+ 1)
 

tools/outputs.nix

@@ -1,7 +1,11 @@
-{ runCommand, linkFarm, haskell }:
+{ runCommand, linkFarm, haskell, lib }:
 
 let
-  run = name: hsFile:
+  inherit (lib) concatMapStringsSep escapeShellArg;
+
+  run = name: hsFile: run' name hsFile {};
+
+  run' = name: hsFile: { sed ? [] }:
     {
       inherit name;
       path = runCommand "phrasebook-output-${name}.txt"
@@ -10,7 +14,7 @@ let
           inherit hsFile;
         }
         ''
-          runhaskell "$hsFile" > $out
+          runhaskell "$hsFile" ${concatMapStringsSep " " (x: "| sed -e ${escapeShellArg x}") sed} > $out
         '';
     };
 
@@ -22,8 +26,8 @@ in
     (run "hashing.txt" ../hashing.hs)
     (run "hello-world.txt" ../hello-world.hs)
     (run "mutable-references.txt" ../mutable-references.hs)
-    (run "threads.txt" ../threads.hs)
+    (run' "threads.txt" ../threads.hs { sed = ["s!^fork.*$!...!"]; })
     (run "timeouts.txt" ../timeouts.hs)
-    (run "transactions.txt" ../transactions.hs)
+    (run' "transactions.txt" ../transactions.hs { sed = ["s!\\[.*\\]!...!"]; })
     (run "variables.txt" ../variables.hs)
   ]

transactions.hs

@@ -1,15 +1,16 @@
-import Control.Concurrent (forkIO, threadDelay)
-import Control.Monad (forever, when)
-import Data.Foldable (asum, for_)
-import Data.Traversable (for)
-import System.IO
-
 import Control.Monad.STM
 import Control.Concurrent.STM.TVar
 
+import Control.Concurrent (forkIO, threadDelay)
+
 import System.Random.MWC (createSystemRandom, uniformR)
+
 import qualified Data.Sequence as Seq
 
+import Control.Monad (forever, when)
+import Data.Foldable (asum, for_)
+import Data.Traversable (for)
+
 main =
   do
     accountList <-
@@ -24,12 +25,15 @@ main =
             i <- uniformR (1, Seq.length accountSeq) rng
             return (Seq.index accountSeq (i - 1))
 
-    for_ [1..20] $ \_ ->
+    for_ [1..500] $ \_ ->
         forkIO $
           do
             rng <- createSystemRandom
             forever $
               do
+                d <- uniformR (10, 50) rng
+                threadDelay d
+
                 sender    <- randomAccount rng
                 recipient <- randomAccount rng
 
@@ -53,5 +57,5 @@ main =
       do
         threadDelay 500000
         balances <- atomically (for accountList readTVar)
-        hPutStrLn stderr (show balances)
+        putStrLn (show balances)
         putStrLn ("Total: " ++ show (sum balances))