[project @ 1998-06-04 16:15:10 by simonm]

Add a few simple concurrency tests.  More to come.

ghc/tests/concurrent/Makefile

+#-----------------------------------------------------------------------------
+# $Id: Makefile,v 1.1 1998/06/04 16:15:10 simonm Exp $
+
+TOP = ..
+include $(TOP)/mk/boilerplate.mk
+
+SUBDIRS = should_run
+
+include $(TOP)/mk/target.mk
+
+

ghc/tests/concurrent/should_run/conc001.hs

+module Main where
+
+import Concurrent
+
+-- two processes, one MVar communication.
+
+main = do
+  s <- newEmptyMVar
+  let 
+    reader = do
+	str <- takeMVar s
+  	putStr str
+
+  forkIO reader
+  putMVar s "hello world\n"

ghc/tests/concurrent/should_run/conc001.stdout

+hello world

ghc/tests/concurrent/should_run/conc002.hs

+module Main where
+
+import Concurrent
+
+main = do
+  c <- newChan
+  let 
+    reader = do
+	char <- readChan c
+  	if (char == '\n') 
+		then return () 
+		else do	putChar char; reader	
+  forkIO reader
+  writeList2Chan c "Hello World\n"
+

ghc/tests/concurrent/should_run/conc002.stdout

+Hello World
\ No newline at end of file

ghc/tests/concurrent/should_run/conc003.hs

+module Main where
+
+import Concurrent
+
+-- simple handshaking using two MVars, 
+-- must context switch twice for each character.
+
+main = do
+  ready <- newEmptyMVar
+  datum <- newEmptyMVar
+  let 
+    reader = do
+	putMVar ready ()
+	char <- takeMVar datum
+  	if (char == '\n') 
+		then return () 
+		else do	putChar char; reader
+
+    writer "" = do
+	takeMVar ready
+	putMVar datum '\n'
+    writer (c:cs) = do
+	takeMVar ready
+	putMVar datum c
+	writer cs
+
+  forkIO reader
+  writer "Hello World"

ghc/tests/concurrent/should_run/conc003.stdout

+Hello World
\ No newline at end of file