reorder repo parameters last

Many functions took the repo as their first parameter. Changing it
consistently to be the last parameter allows doing some useful things with
currying, that reduce boilerplate.

In particular, g <- gitRepo is almost never needed now, instead
use inRepo to run an IO action in the repo, and fromRepo to get
a value from the repo.

This also provides more opportunities to use monadic and applicative
combinators.

Annex/Content.hs

@@ -37,18 +37,18 @@ import Config
 {- Checks if a given key is currently present in the gitAnnexLocation. -}
 inAnnex :: Key -> Annex Bool
 inAnnex key = do
-	g <- gitRepo
-	when (Git.repoIsUrl g) $ error "inAnnex cannot check remote repo"
-	liftIO $ doesFileExist $ gitAnnexLocation g key
+	whenM (fromRepo Git.repoIsUrl) $
+		error "inAnnex cannot check remote repo"
+	inRepo $ doesFileExist . gitAnnexLocation key
 
 {- Calculates the relative path to use to link a file to a key. -}
 calcGitLink :: FilePath -> Key -> Annex FilePath
 calcGitLink file key = do
-	g <- gitRepo
 	cwd <- liftIO getCurrentDirectory
 	let absfile = fromMaybe whoops $ absNormPath cwd file
+	top <- fromRepo Git.workTree
 	return $ relPathDirToFile (parentDir absfile) 
-			(Git.workTree g) </> ".git" </> annexLocation key
+			top </> ".git" </> annexLocation key
 	where
 		whoops = error $ "unable to normalize " ++ file
 
@@ -65,8 +65,7 @@ logStatus key status = do
  - the annex as a key's content. -}
 getViaTmp :: Key -> (FilePath -> Annex Bool) -> Annex Bool
 getViaTmp key action = do
-	g <- gitRepo
-	let tmp = gitAnnexTmpLocation g key
+	tmp <- fromRepo $ gitAnnexTmpLocation key
 
 	-- Check that there is enough free disk space.
 	-- When the temp file already exists, count the space
@@ -84,8 +83,7 @@ getViaTmp key action = do
 
 prepTmp :: Key -> Annex FilePath
 prepTmp key = do
-	g <- gitRepo
-	let tmp = gitAnnexTmpLocation g key
+	tmp <- fromRepo $ gitAnnexTmpLocation key
 	liftIO $ createDirectoryIfMissing True (parentDir tmp)
 	return tmp
 
@@ -162,8 +160,7 @@ checkDiskSpace' adjustment key = do
  -}
 moveAnnex :: Key -> FilePath -> Annex ()
 moveAnnex key src = do
-	g <- gitRepo
-	let dest = gitAnnexLocation g key
+	dest <- fromRepo $ gitAnnexLocation key
 	let dir = parentDir dest
 	e <- liftIO $ doesFileExist dest
 	if e
@@ -177,8 +174,7 @@ moveAnnex key src = do
 
 withObjectLoc :: Key -> ((FilePath, FilePath) -> Annex a) -> Annex a
 withObjectLoc key a = do
-	g <- gitRepo
-	let file = gitAnnexLocation g key
+	file <- fromRepo $gitAnnexLocation key
 	let dir = parentDir file
 	a (dir, file)
 
@@ -201,9 +197,9 @@ fromAnnex key dest = withObjectLoc key $ \(dir, file) -> liftIO $ do
  - returns the file it was moved to. -}
 moveBad :: Key -> Annex FilePath
 moveBad key = do
-	g <- gitRepo
-	let src = gitAnnexLocation g key
-	let dest = gitAnnexBadDir g </> takeFileName src
+	src <- fromRepo $ gitAnnexLocation key
+	bad <- fromRepo $ gitAnnexBadDir
+	let dest = bad </> takeFileName src
 	liftIO $ do
 		createDirectoryIfMissing True (parentDir dest)
 		allowWrite (parentDir src)
@@ -214,9 +210,7 @@ moveBad key = do
 
 {- List of keys whose content exists in .git/annex/objects/ -}
 getKeysPresent :: Annex [Key]
-getKeysPresent = do
-	g <- gitRepo
-	getKeysPresent' $ gitAnnexObjectDir g
+getKeysPresent = getKeysPresent' =<< fromRepo gitAnnexObjectDir
 getKeysPresent' :: FilePath -> Annex [Key]
 getKeysPresent' dir = do
 	exists <- liftIO $ doesDirectoryExist dir