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


-- | Extend Haskell data or newtype like in OOP languages
--   
--   This package allows you to extend Haskell data or newtype like in OOP
--   languages.
@package data-extend-generic
@version 0.1.0.0

module Data.Extend.Internal
class GExtend a
gExtend :: GExtend a => a p -> a p -> a p
class Extend a where extend a b = to $ gExtend (from a) (from b)

-- | By default
--   
--   <pre>
--   a `extend` b = a
--   </pre>
--   
--   <pre>
--   Nothing `extend` Just a = Just a
--   </pre>
--   
--   To use the <a>Extend</a> class, simply make your data derive Generic.
--   
--   If "a" is a user defined data type, then all <a>Nothing</a> fields of
--   "a" are replaced by corresponding fields in "b",
--   
--   ie, all <a>Just</a> fields in "a" will override corresponding fields
--   in "b".
extend :: Extend a => a -> a -> a

-- | By default
--   
--   <pre>
--   a `extend` b = a
--   </pre>
--   
--   <pre>
--   Nothing `extend` Just a = Just a
--   </pre>
--   
--   To use the <a>Extend</a> class, simply make your data derive Generic.
--   
--   If "a" is a user defined data type, then all <a>Nothing</a> fields of
--   "a" are replaced by corresponding fields in "b",
--   
--   ie, all <a>Just</a> fields in "a" will override corresponding fields
--   in "b".
extend :: (Extend a, Generic a, GExtend (Rep a)) => a -> a -> a
instance (Data.Extend.Internal.GExtend (GHC.Generics.K1 i (m a)), GHC.Base.Alternative m, Data.Extend.Internal.GExtend b) => Data.Extend.Internal.GExtend (GHC.Generics.K1 i (m a) GHC.Generics.:*: b)
instance Data.Extend.Internal.GExtend GHC.Generics.U1
instance Data.Extend.Internal.Extend a => Data.Extend.Internal.GExtend (GHC.Generics.K1 i a)
instance (Data.Extend.Internal.GExtend a, Data.Extend.Internal.GExtend b) => Data.Extend.Internal.GExtend (a GHC.Generics.:*: b)
instance (Data.Extend.Internal.GExtend a, Data.Extend.Internal.GExtend b) => Data.Extend.Internal.GExtend (a GHC.Generics.:+: b)
instance Data.Extend.Internal.GExtend a => Data.Extend.Internal.GExtend (GHC.Generics.M1 i c a)
instance Data.Extend.Internal.Extend a => Data.Extend.Internal.Extend (GHC.Base.Maybe a)
instance Data.Extend.Internal.Extend a


-- | This package allows you to extend a Haskell data like how you do in
--   OOP.
--   
--   Here is an example use for testing:
--   
--   <pre>
--   data Test = Test | TestA {
--         f1 :: Int,
--         f2 :: Maybe Int,
--         f3 :: Maybe Int
--      } deriving (Show, Generic, Eq)
--   
--   test1A = TestA 1 (Just 1) (Just 3)
--   test2A = TestA 0 Nothing (Just 2)
--   
--   main :: IO ()
--   main = hspec $
--      describe "Data.Extend" $ do
--         specify "Int" $
--            (2 `extend` 1) `shouldBe` (2 :: Int)
--         specify "String" $
--            ("b" `extend` "a") `shouldBe` "b"
--         specify "data 0" $
--            (Test `extend` Test) `shouldBe` Test
--         specify "data 1" $
--            (test2A `extend` test1A) `shouldBe` TestA 0 (Just 1) (Just 2)
--   </pre>
module Data.Extend
class Extend a where extend a b = to $ gExtend (from a) (from b)

-- | By default
--   
--   <pre>
--   a `extend` b = a
--   </pre>
--   
--   <pre>
--   Nothing `extend` Just a = Just a
--   </pre>
--   
--   To use the <a>Extend</a> class, simply make your data derive Generic.
--   
--   If "a" is a user defined data type, then all <a>Nothing</a> fields of
--   "a" are replaced by corresponding fields in "b",
--   
--   ie, all <a>Just</a> fields in "a" will override corresponding fields
--   in "b".
extend :: Extend a => a -> a -> a

-- | By default
--   
--   <pre>
--   a `extend` b = a
--   </pre>
--   
--   <pre>
--   Nothing `extend` Just a = Just a
--   </pre>
--   
--   To use the <a>Extend</a> class, simply make your data derive Generic.
--   
--   If "a" is a user defined data type, then all <a>Nothing</a> fields of
--   "a" are replaced by corresponding fields in "b",
--   
--   ie, all <a>Just</a> fields in "a" will override corresponding fields
--   in "b".
extend :: (Extend a, Generic a, GExtend (Rep a)) => a -> a -> a