-- Hoogle documentation, generated by Haddock
-- See Hoogle, http://www.haskell.org/hoogle/


-- | Simple command line argument parsing
--   
@package getopt-generics
@version 0.5


-- | <tt>getopt-generics</tt> tries to make it very simple to create
--   command line argument parsers. An introductory example can be found in
--   the <a>README</a>.
module System.Console.GetOpt.Generics

-- | Parses command line arguments (gotten from <a>withArgs</a>) and
--   returns the parsed value. This function should be enough for simple
--   use-cases.
--   
--   May throw the following exceptions:
--   
--   <ul>
--   <li><tt><a>ExitFailure</a> 1</tt> in case of invalid options. Error
--   messages are written to <tt>stderr</tt>.</li>
--   <li><tt><a>ExitSuccess</a></tt> in case <tt>--help</tt> is given.
--   (<tt><a>ExitSuccess</a></tt> behaves like a normal exception, except
--   that -- if uncaught -- the process will exit with exit-code
--   <tt>0</tt>.) Help output is written to <tt>stdout</tt>.</li>
--   </ul>
getArguments :: (Generic a, HasDatatypeInfo a, All2 Option (Code a)) => IO a

-- | Like <a>getArguments</a> but allows you to pass in <a>Modifier</a>s.
modifiedGetArguments :: (Generic a, HasDatatypeInfo a, All2 Option (Code a)) => [Modifier] -> IO a

-- | Pure variant of <a>getArguments</a>. Also allows to declare
--   <a>Modifier</a>s.
--   
--   Does not throw any exceptions.
parseArguments :: (Generic a, HasDatatypeInfo a, All2 Option (Code a)) => String -> [Modifier] -> [String] -> Result a

-- | Type to wrap results from the pure parsing functions.
data Result a

-- | The CLI was used correctly and a value of type <tt>a</tt> was
--   successfully constructed.
Success :: a -> Result a

-- | The CLI was used incorrectly. The <a>Result</a> contains a list of
--   error messages.
--   
--   It can also happen that the data type you're trying to use isn't
--   supported. See the <a>README</a> for details.
Errors :: [String] -> Result a

-- | The CLI was used with <tt>--help</tt>. The <a>Result</a> contains the
--   help message.
OutputAndExit :: String -> Result a

-- | <a>Modifier</a>s can be used to customize the command line parser.
data Modifier

-- | <tt>AddShortOption fieldName c</tt> adds the <a>Char</a> <tt>c</tt> as
--   a short option for the field addressed by <tt>fieldName</tt>.
AddShortOption :: String -> Char -> Modifier

-- | <tt>RenameOption fieldName customName</tt> renames the option
--   generated through the <tt>fieldName</tt> by <tt>customName</tt>.
RenameOption :: String -> String -> Modifier

-- | <tt>UseForPositionalArguments fieldName</tt> fills the field addressed
--   by <tt>fieldName</tt> with the positional arguments (i.e. arguments
--   that don't correspond to a flag). The field has to have type
--   <tt>[<a>String</a>]</tt>.
UseForPositionalArguments :: String -> Modifier

-- | Derives <a>AddShortOption</a>s for all fields of the datatype that
--   start with a unique character.
deriveShortOptions :: (HasDatatypeInfo a, SingI (Code a)) => Proxy a -> [Modifier]

-- | Type class for all allowed field types.
--   
--   If you want to use custom field types you should implement an
--   <tt>instance Option YourCustomType</tt> containing implementations of
--   <a>argumentType</a> and <a>parseArgument</a> (the minimal complete
--   definition). For an example see the <a>README</a>.
class Typeable a => Option a where _toOption = ReqArg parseAsFieldState (argumentType (Proxy :: Proxy a)) _emptyOption flagName = Unset ("missing option: --" ++ flagName ++ "=" ++ argumentType (Proxy :: Proxy a)) _accumulate _ x = x
argumentType :: Option a => Proxy a -> String
parseArgument :: Option a => String -> Maybe a
_toOption :: Option a => ArgDescr (FieldState a)
_emptyOption :: Option a => String -> FieldState a
_accumulate :: Option a => a -> a -> a
instance [overlap ok] Typeable FieldState
instance [overlap ok] Option Int
instance [overlap ok] Option String
instance [overlap ok] Option a => Option (Maybe a)
instance [overlap ok] Option a => Option [a]
instance [overlap ok] Option Bool