use a state monad

enormous reworking

1 files changed, 19 insertions, 12 deletions

diff --git a/git-annex.hs b/git-annex.hs
index 7785e4f2d..935be2f1e 100644
--- a/git-annex.hs
+++ b/git-annex.hs
@@ -1,36 +1,43 @@
 {- git-annex main program
  - -}
 
+import Control.Monad.State
 import System.IO
 import System.Environment
 import Control.Exception
 import CmdLine
+import Types
 import Annex
 
 main = do
 	args <- getArgs
-	(mode, files) <- argvToMode args
-	
+	(mode, params) <- argvToMode args
 	state <- startAnnex
+	tryRun state mode 0 0 params
 
-	tryRun 0 0 $ map (\f -> dispatch state mode f) files
-
-{- Tries to run a series of actions, not stopping if some error out,
- - and propigating an overall error status at the end. -}
-tryRun errnum oknum [] = do
+{- Processes each param in the list by dispatching the handler function
+ - for the user-selection operation mode. Catches exceptions, not stopping
+ - if some error out, and propigates an overall error status at the end.
+ -
+ - This runs in the IO monad, not in the Annex monad. It seems that
+ - exceptions can only be caught in the IO monad, not in a stacked monad;
+ - or more likely I missed an easy way to do it. So, I have to laboriously
+ - thread AnnexState through this function.
+ -}
+tryRun :: AnnexState -> Mode -> Int -> Int -> [String] -> IO ()
+tryRun state mode errnum oknum [] = do
 	if (errnum > 0)
 		then error $ (show errnum) ++ " failed ; " ++ show (oknum) ++ " ok"
 		else return ()
-tryRun errnum oknum (a:as) = do
-	result <- try (a)::IO (Either SomeException ())
+tryRun state mode errnum oknum (f:fs) = do
+	result <- try (runAnnexState state (dispatch mode f))::IO (Either SomeException ((), AnnexState))
 	case (result) of
 		Left err -> do
 			showErr err
-			tryRun (errnum + 1) oknum as
-		Right _ -> tryRun errnum (oknum + 1) as
+			tryRun state mode (errnum + 1) oknum fs
+		Right (_,state') -> tryRun state' mode errnum (oknum + 1) fs
 
 {- Exception pretty-printing. -}
-showErr :: SomeException -> IO ()
 showErr e = do
 	hPutStrLn stderr $ "git-annex: " ++ (show e)
 	return ()