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


-- | Type derived JSON parsing using Aeson
--   
--   A library for deriving JSON parsers (using Aeson) by indicating JSON
--   structure at the type level.
@package tyro
@version 0.2.0.0


module Data.Tyro

-- | <tt>Extract a</tt> represents trying to parse JSON to an <tt>a</tt>.
type Extract a = JSBranch '[] a

-- | The type operator '&gt;%&gt; provides a way of describing how to walk
--   down a JSON tree.

-- | The <a>List</a> type operator constructs a parsing type for parsing a
--   list of JSON objects.

-- | <a>unwrap</a> unwraps a value from it's parsing type.
unwrap :: JSBranch xs a -> a

-- | <a>Tyro</a> is an abstract type representing a parser that walks down
--   a JSON tree.
data Tyro

-- | <a>extract</a> is the value which represents halting the walk along
--   the JSON tree, and pulling out the value there.
extract :: Tyro

-- | <a>&gt;%&gt;</a> allows you to specify a subtree indexed by a key.
--   It's right associative, so chains of keys can be specified without
--   parenthesese.
(>%>) :: String -> Tyro -> Tyro
infixr 9 >%>

-- | <a>%%&gt;</a> tries to parse a ByteString along a <a>Tyro</a> to
--   obtain a value
(%%>) :: (FromJSON a) => ByteString -> Tyro -> Maybe a
infixl 8 %%>

-- | <a>JSBranch</a> is a dependent datatype which represents a walk down a
--   JSON tree. <tt>JSBranch ["key1", "key2"] a</tt> represents the walk
--   "take the value at <tt>key1</tt> and then the value at <tt>key2</tt>,
--   and (try to) interpret that as an <tt>a</tt>".
data JSBranch :: [Symbol] -> * -> *
instance GHC.Show.Show Data.Tyro.Tyro
instance GHC.Classes.Eq Data.Tyro.Tyro
instance (Data.Aeson.Types.FromJSON.FromJSON a, Data.Singletons.SingI xs) => Data.Aeson.Types.FromJSON.FromJSON (Data.Tyro.JSBranch xs a)