Add Ord instance to Slug

CHANGELOG.md

@@ -3,6 +3,7 @@
 ## Unreleased
 
 - Remove Ex03_Documentation.hs (moved to separate repo, `ema-docs`)
+- Add `Ord` instance to `Slug`
 
 ## 0.1.0.0 -- 2021-04-26
 

src/Ema/Route/Slug.hs

@@ -6,7 +6,7 @@ import qualified Data.Text as T
 
 -- | An URL path is made of multiple slugs, separated by '/'
 newtype Slug = Slug {unSlug :: Text}
-  deriving (Eq, Show)
+  deriving (Eq, Show, Ord)
 
 instance IsString Slug where
   fromString :: HasCallStack => String -> Slug