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Clarify where DefaultSignatures is available

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1 parent fa2ff40 commit 3251a11a4bb09e58bead3f1cef98e2ece4537173 @bos committed Jul 17, 2012
Showing with 3 additions and 3 deletions.
  1. +3 −3 Data/Aeson/Types/Class.hs
@@ -111,8 +111,8 @@ class GFromJSON f where
-- type which is an instance of 'Data'.
--
-- * If your compiler has support for the @DeriveGeneric@ and
--- @DefaultSignatures@ language extensions, @toJSON@ will have a default generic
--- implementation.
+-- @DefaultSignatures@ language extensions (GHC 7.2 and newer),
+-- @toJSON@ will have a default generic implementation.
--
-- To use the latter option, simply add a @deriving 'Generic'@ clause to your
-- datatype and declare a @ToJSON@ instance for your datatype without giving a
@@ -754,7 +754,7 @@ obj .:? key = case H.lookup key obj of
-- from an object without affecting its validity and we know a default
-- value to assign in that case. If the key and value are mandatory,
-- use '(.:)' instead.
---
+--
-- Example usage:
--
-- @ v1 <- o '.:?' \"opt_field_with_dfl\" .!= \"default_val\"

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