Parse durations

1 files changed, 24 insertions, 0 deletions

diff --git a/Data/ConfigManager/Instances.hs b/Data/ConfigManager/Instances.hs
new file mode 100644
index 0000000..0855117
--- /dev/null
+++ b/Data/ConfigManager/Instances.hs
@@ -0,0 +1,24 @@
+{-# LANGUAGE FlexibleInstances #-}
+{-# LANGUAGE UndecidableInstances #-}
+{-# LANGUAGE IncoherentInstances #-}
+{-# OPTIONS_GHC -fno-warn-orphans #-}
+
+module Data.ConfigManager.Instances
+  () where
+
+import qualified Data.Text as T
+import Data.Time.Clock (DiffTime, NominalDiffTime)
+
+import Text.Read (readMaybe)
+
+import Data.ConfigManager.Types.Internal
+import Data.ConfigManager.Parser.Duration (parseDuration)
+
+instance Configured DiffTime where
+  convert value = parseDuration value
+
+instance Configured NominalDiffTime where
+  convert value = realToFrac <$> parseDuration value
+
+instance Read a => Configured a where
+  convert = readMaybe . T.unpack