List installed packages from a repository

lib/SlackBuilder/Package.hs

@@ -5,7 +5,8 @@
 -- | Contains data describing packages, methods to update them and to request
 -- information about them.
 module SlackBuilder.Package
-    ( Download(..)
+    ( DataBaseEntry(..)
+    , Download(..)
     , DownloadTemplate(..)
     , PackageDescription(..)
     , PackageUpdateData(..)
@@ -66,3 +67,15 @@ data Updater = Updater
     , is64 :: Bool
     , getVersion :: Text -> Text -> SlackBuilderT Download
     }
+
+data DataBaseEntry = DataBaseEntry
+    { name :: Text
+    , version :: Text
+    , arch :: Text
+    , build :: Text
+    } deriving Eq
+
+instance Show DataBaseEntry
+  where
+    show DataBaseEntry{..} = Text.unpack
+        $ Text.intercalate "-" [name, version, arch, build]