Update examples

testsuite/shell/simple/Main.hs

@@ -0,0 +1,41 @@
+import System.Plugins
+import StringProcessorAPI
+import System.Console.Readline
+import System.Exit
+
+source = "Plugin.hs"
+stub   = "Plugin.stub"
+symbol = "resource"
+
+main = do s <- makeWith source stub []
+          o <- case s of
+                MakeSuccess _ obj -> do
+                        ls <- load obj ["."] [] symbol
+                        case ls of LoadSuccess m v -> return (m,v)
+                                   LoadFailure err -> error "load failed"
+                MakeFailure e -> mapM_ putStrLn e >> error "compile failed"
+          shell o
+
+shell o@(m,plugin) = do 
+        s <- readline "> "
+        cmd <- case s of 
+                Nothing          -> exitWith ExitSuccess
+                Just (':':'q':_) -> exitWith ExitSuccess
+                Just s           -> addHistory s >> return s
+
+        s  <- makeWith source stub []   -- maybe recompile the source
+        o' <- case s of
+                MakeSuccess ReComp o -> do 
+                        ls <- reload m symbol
+                        case ls of LoadSuccess m' v' -> return (m',v')
+                                   LoadFailure err   -> error "reload failed"
+                MakeSuccess NotReq _ -> return o
+                MakeFailure e -> mapM_ putStrLn e >> shell o
+        eval cmd o'
+        shell o'
+
+eval ":?" _ = putStrLn ":?\n:q\n<string>"
+
+eval s (_,plugin) = let fn = (stringProcessor plugin) in putStrLn (fn s)
+
+