Examples

data Test0 = A | B | C deriving (Generic, Typeable, Show, Eq)
instance ToBSON Test0
instance FromBSON Test0

(fromBSON $ toBSON A) :: Maybe Test0

data Test1 = Test1 String String deriving (Generic, Typeable, Show, Eq)
instance ToBSON Test1
instance FromBSON Test1

(fromBSON $ toBSON $ Test1 "aa" "bb") :: Maybe Test1

data Test2 = Test2 { test20 :: String, test21 :: String } deriving (Generic, Typeable, Show, Eq)
instance ToBSON Test2
instance FromBSON Test2

(fromBSON $ toBSON $ Test2 "aa" "bb") :: Maybe Test2

data Test3 = Test3 { test30 :: Test2, test31 :: String } deriving (Generic, Typeable, Show, Eq)
instance ToBSON Test3
instance FromBSON Test3

(fromBSON $ toBSON $ Test3 (Test2 "aa" "bb") "cc") :: Maybe Test3

data Test4 = Test4 { test4Key :: ObjectKey, test4 :: String } deriving (Generic, Typeable, Show, Eq)
instance ToBSON Test4
instance FromBSON Test4

(fromBSON $ toBSON $ Test4 (ObjectKey . Just $ unsafePerformIO genObjectId) "something") :: Maybe Test4
(fromBSON $ toBSON $ Test4 (ObjectKey Nothing) "something") :: Maybe Test4

data Comment = Comment { author :: String, comments :: [Comment] } deriving (Generic, Typeable, Show, Eq)
instance ToBSON Comment
instance FromBSON Comment

(fromBSON $ toBSON $ Comment "Joe1" [Comment "Joe2" [], Comment "Joe3" [Comment "Joe4" [], Comment "Joe5" []]]) :: Maybe Comment

Representation

toBSON $ Test2 "aa" "bb"

[ test20: "aa", test21: "bb" ]

toBSON $ Test3 (Test2 "aa" "bb") "cc"

[ test30: [ test20: "aa", test21: "bb"], test31: "cc" ]

toBSON $ Test4 (ObjectKey . Just $ unsafePerformIO genObjectId) "something"

[ _id: 4f226c27900faa06ab000001, test4: "something" ]

toBSON $ Test4 (ObjectKey Nothing) "something"

[ test4: "something" ]

toBSON $ Comment "Joe1" [ Comment "Joe2" []
                        , Comment "Joe3" [ Comment "Joe4" []
                                         , Comment "Joe5" []
                                         ]
                        ]

[ author: "Joe1", comments: [ [ author: "Joe2", comments: []]
                            , [ author: "Joe3", comments: [ [ author: "Joe4", comments: []]
                                                          , [ author: "Joe5", comments: []]
                                                          ]]
                            ]]