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diff --git a/users/grfn/xanthous/src/Xanthous/Util/JSON.hs b/users/grfn/xanthous/src/Xanthous/Util/JSON.hs
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+--------------------------------------------------------------------------------
+module Xanthous.Util.JSON
+  ( ReadShowJSON(..)
+  ) where
+--------------------------------------------------------------------------------
+import Xanthous.Prelude
+--------------------------------------------------------------------------------
+import Data.Aeson
+--------------------------------------------------------------------------------
+
+newtype ReadShowJSON a = ReadShowJSON a
+  deriving newtype (Read, Show)
+
+instance Show a => ToJSON (ReadShowJSON a) where
+  toJSON = toJSON . show
+
+instance Read a => FromJSON (ReadShowJSON a) where
+  parseJSON = withText "readable"
+    $ maybe (fail "Could not read") pure . readMay