Improve command-line parser (add OptIntSuffix); make -fliberate-case-threshold dynamic

[ghc-hetmet.git] / compiler / main / CmdLineParser.hs

diff --git a/compiler/main/CmdLineParser.hs b/compiler/main/CmdLineParser.hs
index dfe3125..2a92a32 100644 (file)
--- a/compiler/main/CmdLineParser.hs
+++ b/compiler/main/CmdLineParser.hs
@@ -28,6 +28,7 @@ data OptKind m                -- Suppose the flag is -f
        | Prefix    (String -> m ())    -- -farg 
        | OptPrefix (String -> m ())    -- -f or -farg (i.e. the arg is optional)
        | OptIntSuffix (Maybe Int -> m ())      -- -f or -f=n; pass n to fn
+       | IntSuffix (Int -> m ())               -- -f or -f=n; pass n to fn
        | PassFlag  (String -> m ())    -- -f; pass "-f" fn
        | AnySuffix (String -> m ())    -- -f or -farg; pass entire "-farg" to fn
        | PrefixPred    (String -> Bool) (String -> m ())
@@ -82,15 +83,18 @@ processOneArg action rest arg args
        PassFlag f  | notNull rest -> unknownFlagErr dash_arg
                    | otherwise    -> Right (f dash_arg, args)
 
-       OptIntSuffix f | Just n <- parseInt rest -> Right (f n, args)
+       OptIntSuffix f | null rest               -> Right (f Nothing,  args)
+                      | Just n <- parseInt rest -> Right (f (Just n), args)
                       | otherwise -> Left ("malformed integer argument in " ++ dash_arg)
 
+       IntSuffix f | Just n <- parseInt rest -> Right (f n, args)
+                   | otherwise -> Left ("malformed integer argument in " ++ dash_arg)
+
        OptPrefix f       -> Right (f rest, args)
        AnySuffix f       -> Right (f dash_arg, args)
        AnySuffixPred p f -> Right (f dash_arg, args)
 
 
-
 findArg :: [(String,OptKind a)] -> String -> Maybe (String,OptKind a)
 findArg spec arg
   = case [ (removeSpaces rest, k) 
@@ -107,21 +111,19 @@ arg_ok (SepArg _)           rest arg = null rest
 arg_ok (Prefix _)          rest arg = notNull rest
 arg_ok (PrefixPred p _)     rest arg = notNull rest && p rest
 arg_ok (OptIntSuffix _)            rest arg = True
+arg_ok (IntSuffix _)       rest arg = True
 arg_ok (OptPrefix _)       rest arg = True
 arg_ok (PassFlag _)         rest arg = null rest 
 arg_ok (AnySuffix _)        rest arg = True
 arg_ok (AnySuffixPred p _)  rest arg = p arg
 
-parseInt :: String -> Maybe (Maybe Int)
+parseInt :: String -> Maybe Int
 -- Looks for "433" or "=342", with no trailing gubbins
---   empty string => Just Nothing
---   n or =n     => Just (Just n)
+--   n or =n     => Just n
 --   gibberish    => Nothing
-parseInt s 
-  | null s    = Just Nothing
-  | otherwise = case reads (dropEq s) of
-                 ((n,""):_) -> Just (Just n)
-                 other      -> Nothing
+parseInt s = case reads (dropEq s) of
+               ((n,""):_) -> Just n
+               other      -> Nothing
 
 dropEq :: String -> String
 -- Discards a leading equals sign