Add Item abstraction

1 files changed, 23 insertions, 0 deletions

diff --git a/src/Hakyll/Core/Item/SomeItem.hs b/src/Hakyll/Core/Item/SomeItem.hs
new file mode 100644
index 0000000..c5ba0df
--- /dev/null
+++ b/src/Hakyll/Core/Item/SomeItem.hs
@@ -0,0 +1,23 @@
+--------------------------------------------------------------------------------
+{-# LANGUAGE DeriveDataTypeable        #-}
+{-# LANGUAGE ExistentialQuantification #-}
+module Hakyll.Core.Item.SomeItem
+    ( SomeItem (..)
+    ) where
+
+
+--------------------------------------------------------------------------------
+import           Data.Binary          (Binary)
+import           Data.Typeable        (Typeable)
+
+
+--------------------------------------------------------------------------------
+import           Hakyll.Core.Item
+import           Hakyll.Core.Writable
+
+
+--------------------------------------------------------------------------------
+-- | An existential type, mostly for internal usage.
+data SomeItem = forall a.
+    (Binary a, Typeable a, Writable a) => SomeItem (Item a)
+    deriving (Typeable)