PersistField instance for CI, i.e. case-insensitive DB fields

src/Database/Persist/Class/Local.hs

@@ -0,0 +1,34 @@
+{- This file is part of Vervis.
+ -
+ - Written in 2016 by fr33domlover <fr33domlover@riseup.net>.
+ -
+ - ♡ Copying is an act of love. Please copy, reuse and share.
+ -
+ - The author(s) have dedicated all copyright and related and neighboring
+ - rights to this software to the public domain worldwide. This software is
+ - distributed without any warranty.
+ -
+ - You should have received a copy of the CC0 Public Domain Dedication along
+ - with this software. If not, see
+ - <http://creativecommons.org/publicdomain/zero/1.0/>.
+ -}
+
+-- | 'PersistField' instance for 'CI', for easy case-insensitive DB fields.
+module Database.Persist.Class.Local
+    ( TextCI
+    )
+where
+
+import Prelude
+
+import Data.CaseInsensitive (CI)
+import Data.Text (Text)
+import Database.Persist.Class
+
+import qualified Data.CaseInsensitive as CI
+
+instance (PersistField s, CI.FoldCase s) => PersistField (CI s) where
+    toPersistValue = toPersistValue . CI.original
+    fromPersistValue = fmap CI.mk . fromPersistValue
+
+type TextCI = CI Text

vervis.cabal

@@ -60,6 +60,7 @@ library
                        Data.Text.Lazy.UTF8.Local
                        Data.Time.Clock.Local
                        Data.Tree.Local
+                       Database.Persist.Class.Local
                        Development.DarcsRev
                        Network.SSH.Local
                        Text.FilePath.Local