Derive newtype ToHttpApiData in type Range (#1813)

* Derive newtype `ToHttpApiData` in type `Range`

* add changelog

* re-export `Servant.API.Range`

* undo changes

* undo re-export

Author: kutyel

changelog.d/pr-1813

@@ -0,0 +1,6 @@
+synopsis: Use newtype deriving for ToHttpApiData in the type Range
+packages: servant
+prs: #1813
+description: {
+  Use newtype deriving for ToHttpApiData in the type Range
+}

servant/src/Servant/API/Range.hs

@@ -39,7 +39,7 @@ import           Servant.API
 -- Nothing
 newtype Range (min :: Nat) (max :: Nat) = MkRange {unRange :: Natural}
     deriving stock (Eq, Ord, Show, Generic)
-    deriving newtype (Ix, ToJSON)
+    deriving newtype (Ix, ToJSON, ToHttpApiData)
 
 unsafeRange :: Natural -> Range min max
 unsafeRange = MkRange
@@ -62,9 +62,6 @@ instance (KnownNat min, KnownNat max) => FromJSON (Range min max) where
         n <- modifyFailure (const $ parseErrorMsg @min @max Proxy) $ parseJSON v
         maybe (fail $ parseErrorMsg @min @max Proxy) pure $ mkRange n
 
-instance (KnownNat min, KnownNat max) => ToHttpApiData (Range min max) where
-    toQueryParam = T.pack . show . unRange
-
 instance (KnownNat min, KnownNat max) => FromHttpApiData (Range min max) where
     parseQueryParam v = do
         n <- first (const . T.pack $ parseErrorMsg @min @max Proxy) $ parseQueryParam v