-- | Specify a default value for an option.
--
-- /Note/: Because this modifier means the parser will never fail,
-- do not use it with combinators such as 'some' or 'many', as
-- these combinators continue until a failure occurs.
-- Careless use will thus result in a hang.
value :: HasValue f => a -> Mod f a
value x = Mod id (DefaultProp (Just x) Nothing) id
value :: HasValue f => a -> Mod f a
value x = Mod id (DefaultProp (Just x) Nothing) id
value x = Mod id (DefaultProp (Just x) Nothing) id