Add encodeRecord

Author: elliotdavies

src/Data/Argonaut/Encode/Class.purs

@@ -11,8 +11,13 @@ import Data.Maybe (Maybe(..))
 import Data.String (CodePoint)
 import Data.String.CodePoints as CP
 import Data.String.CodeUnits as CU
+import Data.Symbol (class IsSymbol, SProxy(..), reflectSymbol)
 import Data.Tuple (Tuple(..))
 import Foreign.Object as FO
+import Prim.Row as Row
+import Prim.RowList as RL
+import Record as Record
+import Type.Data.RowList (RLProxy(..))
 
 class EncodeJson a where
   encodeJson :: a -> Json
@@ -70,3 +75,31 @@ instance encodeMap :: (Ord a, EncodeJson a, EncodeJson b) => EncodeJson (M.Map a
 
 instance encodeVoid :: EncodeJson Void where
   encodeJson = absurd
+
+instance encodeRecord :: (GEncodeJson row list, RL.RowToList row list) => EncodeJson (Record row) where
+  encodeJson rec = fromObject $ gEncodeJson rec (RLProxy :: RLProxy list)
+
+
+class GEncodeJson (row :: # Type) (list :: RL.RowList) where
+  gEncodeJson :: Record row -> RLProxy list -> FO.Object Json
+
+instance gEncodeJsonNil :: GEncodeJson row RL.Nil where
+  gEncodeJson _ _ = FO.empty
+
+instance gEncodeJsonCons
+  :: ( EncodeJson value
+     , GEncodeJson row tail
+     , IsSymbol field
+     , Row.Cons field value tail' row
+     )
+  => GEncodeJson row (RL.Cons field value tail) where
+  
+  gEncodeJson row _ =
+    let
+      sProxy :: SProxy field
+      sProxy = SProxy
+    in
+      FO.insert
+        (reflectSymbol sProxy)
+        (encodeJson $ Record.get sProxy row)
+        (gEncodeJson row $ RLProxy :: RLProxy tail)