bbc11eb · typeable/aeson

git.iko.soy/typeable/aeson

Add ./ operator for traversing Object heirarchies.

./ allows an Object heirarchy to be traversed without parsing anything. If any of the path components is missing or the wrong type, it returns Missing.

commitbbc11eb1086f0af5e1fe9e4a0d2d5768e91f2979 authorJeremy Fitzhardinge <jeremy@goop.org> dateThu 17 Feb 2011, 17:42 (16 years ago) parent102d07f

2 files changed+12

compare with master

unifiedsplit

Data/Aeson.hs+1 Data/Aeson/Types.hs+11

Data/Aeson.hs+1

@@ -27,6 +27,7 @@ module Data.Aeson

2727 , (.=?)

2828 , (.:)

2929 , (.:?)

30+ , (./)

3031 , object

3132 -- * Encoding and parsing

3233 , encode

Data/Aeson/Types.hs+11

@@ -33,6 +33,7 @@ module Data.Aeson.Types

3333 , (.=?)

3434 , (.:)

3535 , (.:?)

36+ , (./)

3637 , object

3738 ) where

3839

@@ -213,6 +214,16 @@ obj .:? key = case M.lookup key obj of

213214 Just v -> parseJSON v

214215{-# INLINE (.:?) #-}

215216

217+-- | Traverse a object heirarchy.

218+-- This is useful for traversing a JSON object to get to an

219+-- appropriate place before parsing.

220+(./) :: Value -> Text -> Value

221+(Object obj) ./ key = case M.lookup key obj of

222+ Nothing -> Missing

223+ Just v -> v

224+_ ./ _ = Missing

225+{-# INLINE (./) #-}

226+

216227-- | Create a 'Value' from a list of name\/value 'Pair's. If duplicate

217228-- keys arise, earlier keys and their associated values win.

218229object :: [Pair] -> Value