Prepare for 0.1.1.0 release

Author: andrewthad

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Revision history for json-syntax
 
+## 0.1.1.0 -- 2020-05-01
+
+* Add `encode`.
+
 ## 0.1.0.0 -- 2020-01-20
 
 * Initial release.

json-syntax.cabal

@@ -1,7 +1,7 @@
 cabal-version: 2.2
 name: json-syntax
-version: 0.1.0.0
-synopsis: High-performance JSON parser
+version: 0.1.1.0
+synopsis: High-performance JSON parser and encoder
 description:
   This library parses JSON into a @Value@ type that is consistent with the
   ABNF described in [RFC 7159](https://tools.ietf.org/html/rfc7159). The
@@ -36,7 +36,7 @@ library
     , bytesmith >=0.3.2 && <0.4
     , bytestring >=0.10.8 && <0.11
     , primitive >=0.7 && <0.8
-    , scientific-notation >=0.1.1 && <0.2
+    , scientific-notation >=0.1.2 && <0.2
     , text-short >=0.1.3 && <0.2
   hs-source-dirs: src
   default-language: Haskell2010

src/Json/Query.hs

@@ -0,0 +1,37 @@
+module Json.Query
+  ( Path(..)
+  , query
+  ) where
+
+-- Revisit this later.
+-- Do not release this library with this module still here.
+
+data Path
+  = Key {-# UNPACK #-} !ShortText !Path
+    -- ^ JSON path element of a key into an object, \"object.key\".
+  | Index {-# UNPACK #-} !Int !Path
+    -- ^ JSON path element of an index into an array, \"array[index]\".
+  | Nil
+
+query :: Path -> Value -> Maybe Value
+query = go where
+  go Nil v = Just v
+  go (Key k p) (Object mbrs) = foldr
+    (\(Member key val) other -> if key == k
+      then Just val
+      else other
+    ) Nothing mbrs >>= go p
+  go (Index i p) (Array vs) = Chunks.index vs i >>= go p
+  go _ _ = Nothing
+
+-- Example Use:
+-- data Foo = Foo String String String
+-- object :: Parser Value (Chunks _)
+-- myParser :: Parser Value Foo
+-- myParser =
+--   object
+--   >->
+--   Foo
+--     <$> path "foo"
+--     <*> (path "bar" >-> object >-> path "baz")
+--     <*> path "gaz"