aeson-lens (empty) → 0.1.0.0
raw patch · 5 files changed
+171/−0 lines, 5 filesdep +aesondep +basedep +bytestringsetup-changed
Dependencies added: aeson, base, bytestring, doctest, lens, text, unordered-containers, vector
Files
- Data/Aeson/Lens.hs +102/−0
- LICENSE +30/−0
- Setup.hs +2/−0
- aeson-lens.cabal +33/−0
- doctest.hs +4/−0
+ Data/Aeson/Lens.hs view
@@ -0,0 +1,102 @@+{-# LANGUAGE FlexibleContexts #-}+{-# LANGUAGE OverloadedStrings #-}+{-# LANGUAGE ViewPatterns #-}++module Data.Aeson.Lens (+ ValueIx(..),+ valueAt,+ arr, obj,+ ) where++import Control.Applicative+import Control.Lens+import Data.Aeson+import qualified Data.HashMap.Strict as HMS+import Data.Maybe+import Data.Monoid+import qualified Data.Text as T+import qualified Data.Vector as V++-- $setup+-- >>> import Data.Maybe+-- >>> import qualified Data.ByteString.Lazy.Char8 as L+-- >>> import Data.Text ()+-- >>> let v = decode (L.pack "{\"foo\": {\"baz\": 3.14}, \"bar\": [123, false, null]}") :: Maybe Value++data ValueIx = ArrIx Int | ObjIx T.Text++-- | Lens of Value+valueAt :: (ToJSON v, FromJSON v)+ => ValueIx+ -> SimpleIndexedLens ValueIx (Maybe Value) (Maybe v)+valueAt k = index $ \f (fmap toJSON -> v) -> (go k v) <$> f k (lu k v) where+ go (ObjIx ix) (Just (Object o)) Nothing = Just $ Object $ HMS.delete ix o+ go (ObjIx ix) (Just (Object o)) (Just v) = Just $ Object $ HMS.insert ix (toJSON v) o+ go (ObjIx ix) _ (Just v) = Just $ Object $ HMS.fromList [(ix, toJSON v)]+ go (ArrIx ix) (Just (Array a)) Nothing = Just $ Array $ updateV ix Null a+ go (ArrIx ix) (Just (Array a)) (Just v) = Just $ Array $ updateV ix (toJSON v) a+ go (ArrIx ix) _ (Just v) = Just $ Array $ updateV ix (toJSON v) mempty+ go _ v _ = v++ lu (ObjIx ix) (Just (Object o)) = fromJSONMaybe =<< HMS.lookup ix o+ lu (ArrIx ix) (Just (Array a)) | ix >= 0 && ix < V.length a = fromJSONMaybe $ a V.! ix+ lu _ _ = Nothing++updateV :: Int -> Value -> V.Vector Value -> V.Vector Value+updateV i v a+ | i >= V.length a =+ updateV i v $ V.generate (i + 1) $ \ii -> fromMaybe Null $ a `V.indexM` ii+ | otherwise =+ a V.// [(i, v)]++fromJSONMaybe :: FromJSON a => Value -> Maybe a+fromJSONMaybe v = case fromJSON v of+ Error _ -> Nothing+ Success a -> Just a++-- | Lens of Array+--+-- >>> L.unpack $ encode v+-- "{\"bar\":[123,false,null],\"foo\":{\"baz\":3.14}}"+-- >>> v ^. obj (T.pack "bar") . arr 1 :: Maybe Bool+-- Just False+-- >>> v ^. obj (T.pack "bar") . arr 1 :: Maybe String+-- Nothing+-- >>> v ^. obj (T.pack "bar") . arr 3 :: Maybe Value+-- Nothing+-- >>> v ^. arr 0 :: Maybe Value+-- Nothing+-- >>> let x = arr 0 .~ Just 1 $ Nothing+-- >>> L.unpack $ encode x+-- "[1]"+-- >>> let y = arr 1 .~ Just "hoge" $ x+-- >>> L.unpack $ encode y+-- "[1,\"hoge\"]"+-- >>> let z = arr 0 .~ Just False $ y+-- >>> L.unpack $ encode z+-- "[false,\"hoge\"]"+arr :: (ToJSON v, FromJSON v)+ => Int+ -> SimpleIndexedLens ValueIx (Maybe Value) (Maybe v)+arr = valueAt . ArrIx++-- | Lens of Object+--+-- >>> v ^. obj (T.pack "foo") . obj (T.pack "baz") :: Maybe Double+-- Just 3.14+-- >>> v ^. obj (T.pack "foo") . obj (T.pack "baz") :: Maybe Object+-- Nothing+-- >>> v ^. obj (T.pack "foo") . obj (T.pack "hoge") :: Maybe Value+-- Nothing+-- >>> v ^. obj (T.pack "hoge") :: Maybe Value+-- Nothing+-- >>> let w = obj (T.pack "a") .~ Just 2.23 $ Nothing+-- >>> L.unpack $ encode w+-- "{\"a\":2.23}"+-- >>> let x = obj (T.pack "b") . obj (T.pack "c") .~ Just True $ w+-- >>> L.unpack $ encode x+-- "{\"b\":{\"c\":true},\"a\":2.23}"+obj :: (ToJSON v, FromJSON v)+ => T.Text+ -> SimpleIndexedLens ValueIx (Maybe Value) (Maybe v)+obj = valueAt . ObjIx
+ LICENSE view
@@ -0,0 +1,30 @@+Copyright (c) 2012, Hideyuki Tanaka++All rights reserved.++Redistribution and use in source and binary forms, with or without+modification, are permitted provided that the following conditions are met:++ * Redistributions of source code must retain the above copyright+ notice, this list of conditions and the following disclaimer.++ * Redistributions in binary form must reproduce the above+ copyright notice, this list of conditions and the following+ disclaimer in the documentation and/or other materials provided+ with the distribution.++ * Neither the name of Hideyuki Tanaka nor the names of other+ contributors may be used to endorse or promote products derived+ from this software without specific prior written permission.++THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ Setup.hs view
@@ -0,0 +1,2 @@+import Distribution.Simple+main = defaultMain
+ aeson-lens.cabal view
@@ -0,0 +1,33 @@+name: aeson-lens+version: 0.1.0.0+synopsis: Lens of Aeson+description: Lens of Aeson+license: BSD3+license-file: LICENSE+author: Hideyuki Tanaka+maintainer: tanaka.hideyuki@gmail.com+copyright: (c) 2012, Hideyuki Tanaka+category: Data+build-type: Simple+cabal-version: >=1.8++source-repository head+ type: git+ location: https://github.com/tanakh/aeson-lens.git++library+ exposed-modules: Data.Aeson.Lens+ build-depends: base ==4.5.*++ , aeson >=0.6+ , lens >=3.0+ , text >=0.11+ , bytestring >=0.9+ , vector >=0.9+ , unordered-containers >=0.2.2++test-suite doctest+ type: exitcode-stdio-1.0+ main-is: doctest.hs+ build-depends: base+ , doctest >=0.9
+ doctest.hs view
@@ -0,0 +1,4 @@+import Test.DocTest++main :: IO ()+main = doctest ["Data/Aeson/Lens.hs"]