Implement isEmpty for Data.Map

IHP/HaskellSupport.hs

@@ -50,6 +50,7 @@ import qualified Data.Attoparsec.ByteString.Char8 as Attoparsec
 import Data.String.Conversions (cs, ConvertibleStrings (..))
 import qualified Debug.Trace
 import qualified Data.Text as Text
+import qualified Data.Map as Map
 import qualified Data.ByteString.Char8 as ByteString
 import qualified Data.Aeson.Key as Aeson
 
@@ -86,6 +87,10 @@ instance IsEmpty UUID.UUID where
     isEmpty uuid = UUID.nil == uuid
     {-# INLINE isEmpty #-}
 
+instance IsEmpty (Map a b) where
+    isEmpty = Map.null    
+    {-# INLINE isEmpty #-}
+
 ifOrEmpty :: (Monoid a) => Bool -> a -> a
 ifOrEmpty bool a = if bool then a else mempty
 {-# INLINE ifOrEmpty #-}
@@ -445,4 +450,4 @@ allEnumValues = enumFrom (toEnum 0)
 instance ConvertibleStrings ByteString Aeson.Key where
     convertString byteString = Aeson.fromText (cs byteString)
 instance ConvertibleStrings Text Aeson.Key where
-    convertString text = Aeson.fromText text
+    convertString text = Aeson.fromText text