module Options.Applicative.Common (
Parser,
liftOpt,
showOption,
ParserInfo(..),
ParserPrefs(..),
runParserInfo,
runParserFully,
runParser,
evalParser,
mapParser,
treeMapParser,
optionNames
) where
import Control.Applicative
import Control.Monad (guard, mzero, msum, when, liftM)
import Control.Monad.Trans.Class (lift)
import Control.Monad.Trans.State (StateT(..), get, put, runStateT)
import Data.List (isPrefixOf)
import Data.Maybe (maybeToList, isJust, isNothing)
import Prelude
import Options.Applicative.Internal
import Options.Applicative.Types
showOption :: OptName -> String
showOption (OptLong n) = "--" ++ n
showOption (OptShort n) = '-' : [n]
optionNames :: OptReader a -> [OptName]
optionNames (OptReader names _ _) = names
optionNames (FlagReader names _) = names
optionNames _ = []
isOptionPrefix :: OptName -> OptName -> Bool
isOptionPrefix (OptShort x) (OptShort y) = x == y
isOptionPrefix (OptLong x) (OptLong y) = x `isPrefixOf` y
isOptionPrefix _ _ = False
liftOpt :: Option a -> Parser a
liftOpt = OptP
argMatches :: MonadP m => OptReader a -> String
-> Maybe (StateT Args m a)
argMatches opt arg = case opt of
ArgReader rdr -> Just . lift $
runReadM (crReader rdr) arg
CmdReader _ _ f ->
flip fmap (f arg) $ \subp -> StateT $ \args -> do
prefs <- getPrefs
let runSubparser
| prefBacktrack prefs = \i a ->
runParser (infoPolicy i) CmdStart (infoParser i) a
| otherwise = \i a
-> (,) <$> runParserInfo i a <*> pure []
enterContext arg subp *> runSubparser subp args <* exitContext
_ -> Nothing
optMatches :: MonadP m => Bool -> OptReader a -> OptWord -> Maybe (StateT Args m a)
optMatches disambiguate opt (OptWord arg1 val) = case opt of
OptReader names rdr no_arg_err -> do
guard $ has_name arg1 names
Just $ do
args <- get
let mb_args = uncons $ maybeToList val ++ args
let missing_arg = missingArgP (no_arg_err $ showOption arg1) (crCompleter rdr)
(arg', args') <- maybe (lift missing_arg) return mb_args
put args'
lift $ runReadM (withReadM (errorFor arg1) (crReader rdr)) arg'
FlagReader names x -> do
guard $ has_name arg1 names
guard $ is_short arg1 || isNothing val
Just $ do
args <- get
let val' = (\s -> '-' : s) <$> val
put $ maybeToList val' ++ args
return x
_ -> Nothing
where
errorFor name msg = "option " ++ showOption name ++ ": " ++ msg
is_short (OptShort _) = True
is_short (OptLong _) = False
has_name a
| disambiguate = any (isOptionPrefix a)
| otherwise = elem a
isArg :: OptReader a -> Bool
isArg (ArgReader _) = True
isArg _ = False
data OptWord = OptWord OptName (Maybe String)
parseWord :: String -> Maybe OptWord
parseWord ('-' : '-' : w) = Just $ let
(opt, arg) = case span (/= '=') w of
(_, "") -> (w, Nothing)
(w', _ : rest) -> (w', Just rest)
in OptWord (OptLong opt) arg
parseWord ('-' : w) = case w of
[] -> Nothing
(a : rest) -> Just $ let
arg = rest <$ guard (not (null rest))
in OptWord (OptShort a) arg
parseWord _ = Nothing
searchParser :: Monad m
=> (forall r . Option r -> NondetT m r)
-> Parser a -> NondetT m (Parser a)
searchParser _ (NilP _) = mzero
searchParser f (OptP opt) = liftM pure (f opt)
searchParser f (MultP p1 p2) = foldr1 (<!>)
[ do p1' <- searchParser f p1
return (p1' <*> p2)
, do p2' <- searchParser f p2
return (p1 <*> p2') ]
searchParser f (AltP p1 p2) = msum
[ searchParser f p1
, searchParser f p2 ]
searchParser f (BindP p k) = msum
[ do p' <- searchParser f p
return $ BindP p' k
, case evalParser p of
Nothing -> mzero
Just aa -> searchParser f (k aa) ]
searchOpt :: MonadP m => ParserPrefs -> OptWord -> Parser a
-> NondetT (StateT Args m) (Parser a)
searchOpt pprefs w = searchParser $ \opt -> do
let disambiguate = prefDisambiguate pprefs
&& optVisibility opt > Internal
case optMatches disambiguate (optMain opt) w of
Just matcher -> lift matcher
Nothing -> mzero
searchArg :: MonadP m => String -> Parser a
-> NondetT (StateT Args m) (Parser a)
searchArg arg = searchParser $ \opt -> do
when (isArg (optMain opt)) cut
case argMatches (optMain opt) arg of
Just matcher -> lift matcher
Nothing -> mzero
stepParser :: MonadP m => ParserPrefs -> ArgPolicy -> String
-> Parser a -> NondetT (StateT Args m) (Parser a)
stepParser _ AllPositionals arg p =
searchArg arg p
stepParser pprefs ForwardOptions arg p = case parseWord arg of
Just w -> searchOpt pprefs w p <|> searchArg arg p
Nothing -> searchArg arg p
stepParser pprefs _ arg p = case parseWord arg of
Just w -> searchOpt pprefs w p
Nothing -> searchArg arg p
runParser :: MonadP m => ArgPolicy -> IsCmdStart -> Parser a -> Args -> m (a, Args)
runParser policy _ p ("--" : argt) | policy /= AllPositionals
= runParser AllPositionals CmdCont p argt
runParser policy isCmdStart p args = case args of
[] -> exitP isCmdStart policy p result
(arg : argt) -> do
prefs <- getPrefs
(mp', args') <- do_step prefs arg argt
case mp' of
Nothing -> hoistMaybe result <|> parseError arg p
Just p' -> runParser (newPolicy arg) CmdCont p' args'
where
result = (,) <$> evalParser p <*> pure args
do_step prefs arg argt = (`runStateT` argt)
. disamb (not (prefDisambiguate prefs))
$ stepParser prefs policy arg p
newPolicy a = case policy of
NoIntersperse -> if isJust (parseWord a) then NoIntersperse else AllPositionals
x -> x
parseError :: MonadP m => String -> Parser x -> m a
parseError arg = errorP . UnexpectedError arg . SomeParser
runParserInfo :: MonadP m => ParserInfo a -> Args -> m a
runParserInfo i = runParserFully (infoPolicy i) (infoParser i)
runParserFully :: MonadP m => ArgPolicy -> Parser a -> Args -> m a
runParserFully policy p args = do
(r, args') <- runParser policy CmdStart p args
case args' of
[] -> return r
a:_ -> parseError a (pure ())
evalParser :: Parser a -> Maybe a
evalParser (NilP r) = r
evalParser (OptP _) = Nothing
evalParser (MultP p1 p2) = evalParser p1 <*> evalParser p2
evalParser (AltP p1 p2) = evalParser p1 <|> evalParser p2
evalParser (BindP p k) = evalParser p >>= evalParser . k
mapParser :: (forall x. OptHelpInfo -> Option x -> b)
-> Parser a -> [b]
mapParser f = flatten . treeMapParser f
where
flatten (Leaf x) = [x]
flatten (MultNode xs) = xs >>= flatten
flatten (AltNode xs) = xs >>= flatten
treeMapParser :: (forall x . OptHelpInfo -> Option x -> b)
-> Parser a
-> OptTree b
treeMapParser g = simplify . go False False False g
where
has_default :: Parser a -> Bool
has_default p = isJust (evalParser p)
go :: Bool -> Bool -> Bool
-> (forall x . OptHelpInfo -> Option x -> b)
-> Parser a
-> OptTree b
go _ _ _ _ (NilP _) = MultNode []
go m d r f (OptP opt)
| optVisibility opt > Internal
= Leaf (f (OptHelpInfo m d r) opt)
| otherwise
= MultNode []
go m d r f (MultP p1 p2) = MultNode [go m d r f p1, go m d r' f p2]
where r' = r || has_positional p1
go m d r f (AltP p1 p2) = AltNode [go m d' r f p1, go m d' r f p2]
where d' = d || has_default p1 || has_default p2
go _ d r f (BindP p k) =
let go' = go True d r f p
in case evalParser p of
Nothing -> go'
Just aa -> MultNode [ go', go True d r f (k aa) ]
has_positional :: Parser a -> Bool
has_positional (NilP _) = False
has_positional (OptP p) = (is_positional . optMain) p
has_positional (MultP p1 p2) = has_positional p1 || has_positional p2
has_positional (AltP p1 p2) = has_positional p1 || has_positional p2
has_positional (BindP p _) = has_positional p
is_positional :: OptReader a -> Bool
is_positional (OptReader {}) = False
is_positional (FlagReader {}) = False
is_positional (ArgReader {}) = True
is_positional (CmdReader {}) = True
simplify :: OptTree a -> OptTree a
simplify (Leaf x) = Leaf x
simplify (MultNode xs) =
case concatMap (remove_mult . simplify) xs of
[x] -> x
xs' -> MultNode xs'
where
remove_mult (MultNode ts) = ts
remove_mult t = [t]
simplify (AltNode xs) =
case concatMap (remove_alt . simplify) xs of
[] -> MultNode []
[x] -> x
xs' -> AltNode xs'
where
remove_alt (AltNode ts) = ts
remove_alt (MultNode []) = []
remove_alt t = [t]