Set version to 6.6.0-beta

Removed `JsonObject::is<T>(k)` and `JsonObject::set(k,v)`
Replaced `T JsonArray::get<T>(i)` with `JsonVariant JsonArray::get(i)`
Replaced `T JsonObject::get<T>(k)` with `JsonVariant JsonObject::get(k)`

.travis.yml

@@ -97,11 +97,19 @@ matrix:
     - compiler: gcc
       env: SCRIPT=coverage
     - os: osx
-      osx_image: xcode6.4
+      osx_image: xcode7.3
       compiler: clang
       env: SCRIPT=cmake
     - os: osx
-      osx_image: xcode7.3
+      osx_image: xcode8.3
+      compiler: clang
+      env: SCRIPT=cmake
+    - os: osx
+      osx_image: xcode9.4
+      compiler: clang
+      env: SCRIPT=cmake
+    - os: osx
+      osx_image: xcode10
       compiler: clang
       env: SCRIPT=cmake SANITIZE=address
     - env: SCRIPT=arduino VERSION=1.6.7 BOARD=arduino:avr:uno
@@ -117,4 +125,6 @@ matrix:
 cache:
   directories:
     - "~/.platformio"
+    - "fuzzing/json_corpus"
+    - "fuzzing/msgpack_corpus"
 script: scripts/travis/$SCRIPT.sh

CHANGELOG.md

@@ -1,10 +1,107 @@
 ArduinoJson: change log
 =======================
 
-v6.2.0-beta
+v6.6.0-beta (2018-11-13)
+-----------
+
+* Removed `JsonArray::is<T>(i)` and `JsonArray::set(i,v)`
+* Removed `JsonObject::is<T>(k)` and `JsonObject::set(k,v)`
+* Replaced `T JsonArray::get<T>(i)` with `JsonVariant JsonArray::get(i)`
+* Replaced `T JsonObject::get<T>(k)` with `JsonVariant JsonObject::get(k)`
+* Added `JSON_STRING_SIZE()`
+* Replacing or removing a value now releases the memory
+* Added `DeserializationError::code()` to be used in switch statements (issue #846)
+
+v6.5.0-beta (2018-10-13)
+-----------
+
+* Added implicit conversion from `JsonArray` and `JsonObject` to `JsonVariant`
+* Allow mixed configuration in compilation units (issue #809)
+* Fixed object keys not being duplicated
+* `JsonPair::key()` now returns a `JsonKey`
+* Increased the default capacity of `DynamicJsonDocument`
+* Fixed `JsonVariant::is<String>()` (closes #763)
+* Added `JsonArrayConst`, `JsonObjectConst`, and `JsonVariantConst`
+* Added copy-constructor and copy-assignment-operator for `JsonDocument` (issue #827)
+
+v6.4.0-beta (2018-09-11)
+-----------
+
+* Copy `JsonArray` and `JsonObject`, instead of storing pointers (issue #780)
+* Added `JsonVariant::to<JsonArray>()` and `JsonVariant::to<JsonObject>()`
+
+v6.3.0-beta (2018-08-31)
+-----------
+
+* Implemented reference semantics for `JsonVariant`
+* Replaced `JsonPair`'s `key` and `value` with `key()` and `value()`
+* Fixed `serializeJson(obj[key], dst)` (issue #794)
+
+> ### BREAKING CHANGES
+>
+> #### JsonVariant
+> 
+> `JsonVariant` now has a semantic similar to `JsonObject` and `JsonArray`.
+> It's a reference to a value stored in the `JsonDocument`.
+> As a consequence, a `JsonVariant` cannot be used as a standalone variable anymore.
+>
+> Old code:
+>
+> ```c++
+> JsonVariant myValue = 42;
+> ```
+>
+> New code:
+>
+> ```c++
+> DynamicJsonDocument doc;
+> JsonVariant myValue = doc.to<JsonVariant>();
+> myValue.set(42);
+> ```
+>
+> #### JsonPair
+>
+> Old code:
+>
+> ```c++
+> for(JsonPair p : myObject) {
+>   Serial.println(p.key);
+>   Serial.println(p.value.as<int>());
+> }
+> ```
+>
+> New code:
+>
+> ```c++
+> for(JsonPair p : myObject) {
+>   Serial.println(p.key());
+>   Serial.println(p.value().as<int>());
+> }
+> ```
+>
+> CAUTION: the key is now read only!
+
+v6.2.3-beta (2018-07-19)
+-----------
+
+* Fixed exception when using Flash strings as object keys (issue #784)
+
+v6.2.2-beta (2018-07-18)
+-----------
+
+* Fixed `invalid application of 'sizeof' to incomplete type '__FlashStringHelper'` (issue #783)
+* Fixed `char[]` not duplicated when passed to `JsonVariant::operator[]`
+
+v6.2.1-beta (2018-07-17)
+-----------
+
+* Fixed `JsonObject` not inserting keys of type `String` (issue #782)
+
+v6.2.0-beta (2018-07-12)
 -----------
 
 * Disabled lazy number deserialization (issue #772)
+* Fixed `JsonVariant::is<int>()` that returned true for empty strings
 * Improved float serialization when `-fsingle-precision-constant` is used
 * Renamed function `RawJson()` to `serialized()`
 * `serializeMsgPack()` now supports values marked with `serialized()`
@@ -30,7 +127,7 @@ v6.2.0-beta
 > object["values"] = serialized("[1,2,3,4]");
 > ```
 
-v6.1.0-beta
+v6.1.0-beta (2018-07-02)
 -----------
 
 * Return `JsonArray` and `JsonObject` by value instead of reference (issue #309)
@@ -60,12 +157,12 @@ v6.1.0-beta
 > }
 > ```
 
-v6.0.1-beta
+v6.0.1-beta (2018-06-11)
 -----------
 
 * Fixed conflicts with `isnan()` and `isinf()` macros (issue #752)
 
-v6.0.0-beta
+v6.0.0-beta (2018-06-07)
 -----------
 
 * Added `DynamicJsonDocument` and `StaticJsonDocument`

CMakeLists.txt

@@ -7,10 +7,16 @@ project(ArduinoJson)
 
 enable_testing()
 
+if(CMAKE_CXX_COMPILER_ID MATCHES "(GNU|Clang)")
+	add_definitions(-DARDUINOJSON_DEBUG)
+	add_compile_options(-g -O0)
+endif()
+
 if(${COVERAGE})
-	set(CMAKE_CXX_FLAGS "-g -O0 -fprofile-arcs -ftest-coverage")
+	set(CMAKE_CXX_FLAGS "-fprofile-arcs -ftest-coverage")
 endif()
 
 include_directories(${CMAKE_CURRENT_LIST_DIR}/src)
 add_subdirectory(third-party/catch)
 add_subdirectory(test)
+add_subdirectory(fuzzing)

README.md

@@ -2,7 +2,7 @@
 
 ---
 
-[![Build status](https://ci.appveyor.com/api/projects/status/m7s53wav1l0abssg/branch/master?svg=true)](https://ci.appveyor.com/project/bblanchon/arduinojson/branch/master) [![Build Status](https://travis-ci.org/bblanchon/ArduinoJson.svg?branch=master)](https://travis-ci.org/bblanchon/ArduinoJson) [![Coverage Status](https://img.shields.io/coveralls/bblanchon/ArduinoJson.svg)](https://coveralls.io/r/bblanchon/ArduinoJson?branch=master) [![Star this project](http://githubbadges.com/star.svg?user=bblanchon&repo=ArduinoJson&style=flat&color=fff&background=007ec6)](https://github.com/bblanchon/ArduinoJson)
+[![Build status](https://ci.appveyor.com/api/projects/status/m7s53wav1l0abssg/branch/6.x?svg=true)](https://ci.appveyor.com/project/bblanchon/arduinojson/branch/6.x) [![Build Status](https://travis-ci.org/bblanchon/ArduinoJson.svg?branch=6.x)](https://travis-ci.org/bblanchon/ArduinoJson) [![Coverage Status](https://img.shields.io/coveralls/bblanchon/ArduinoJson.svg)](https://coveralls.io/r/bblanchon/ArduinoJson?branch=6.x) [![Star this project](http://githubbadges.com/star.svg?user=bblanchon&repo=ArduinoJson&style=flat&color=fff&background=007ec6)](https://github.com/bblanchon/ArduinoJson)
 
 ArduinoJson is a C++ JSON library for Arduino and IoT (Internet Of Things).
 

appveyor.yml

@@ -1,4 +1,4 @@
-version: 6.0.1.{build}
+version: 6.4.0.{build}
 environment:
   matrix:
   - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2017

examples/JsonParserExample/JsonParserExample.ino

@@ -19,9 +19,9 @@ void setup() {
   StaticJsonDocument<200> doc;
 
   // StaticJsonDocument<N> allocates memory on the stack, it can be
-  // replaced by DynamicJsonObject which allocates in the heap.
+  // replaced by DynamicJsonDocument which allocates in the heap.
   //
-  // DynamicJsonObject doc(200);
+  // DynamicJsonDocument doc(200);
 
   // JSON input string.
   //

fuzzing/CMakeLists.txt

@@ -0,0 +1,13 @@
+# ArduinoJson - arduinojson.org
+# Copyright Benoit Blanchon 2014-2018
+# MIT License
+
+add_executable(msgpack_fuzzer
+	msgpack_fuzzer.cpp
+	fuzzer_main.cpp
+)
+
+add_executable(json_fuzzer
+	json_fuzzer.cpp
+	fuzzer_main.cpp
+)

fuzzing/Makefile

@@ -1,6 +1,6 @@
 # CAUTION: this file is invoked by https://github.com/google/oss-fuzz
 
-CXXFLAGS += -I../src
+CXXFLAGS += -I../src -DARDUINOJSON_DEBUG
 
 all: \
 	$(OUT)/json_fuzzer \

fuzzing/fuzzer_main.cpp

@@ -0,0 +1,50 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2018
+// MIT License
+
+// This file is NOT use by Google's OSS fuzz
+// I only use it to reproduce the bugs found
+
+#include <stdint.h>  // size_t
+#include <stdio.h>   // fopen et al.
+#include <stdlib.h>  // exit
+#include <iostream>
+#include <vector>
+
+extern "C" int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size);
+
+std::vector<uint8_t> read(const char* path) {
+  FILE* f = fopen(path, "rb");
+  if (!f) {
+    std::cerr << "Failed to open " << path << std::endl;
+    exit(1);
+  }
+
+  fseek(f, 0, SEEK_END);
+  size_t size = ftell(f);
+  fseek(f, 0, SEEK_SET);
+
+  std::vector<uint8_t> buffer(size);
+  if (fread(buffer.data(), 1, size, f) != size) {
+    fclose(f);
+    std::cerr << "Failed to read " << path << std::endl;
+    exit(1);
+  }
+
+  fclose(f);
+  return buffer;
+}
+
+int main(int argc, const char* argv[]) {
+  if (argc < 2) {
+    std::cerr << "Usage: msgpack_fuzzer files" << std::endl;
+    return 1;
+  }
+
+  for (int i = 1; i < argc; i++) {
+    std::cout << "Loading " << argv[i] << std::endl;
+    std::vector<uint8_t> buffer = read(argv[i]);
+    LLVMFuzzerTestOneInput(buffer.data(), buffer.size());
+  }
+  return 0;
+}

library.json

@@ -7,7 +7,7 @@
     "type": "git",
     "url": "https://github.com/bblanchon/ArduinoJson.git"
   },
-  "version": "6.2.0-beta",
+  "version": "6.6.0-beta",
   "authors": {
     "name": "Benoit Blanchon",
     "url": "https://blog.benoitblanchon.fr"

library.properties

@@ -1,5 +1,5 @@
 name=ArduinoJson
-version=6.2.0-beta
+version=6.6.0-beta
 author=Benoit Blanchon <blog.benoitblanchon.fr>
 maintainer=Benoit Blanchon <blog.benoitblanchon.fr>
 sentence=An efficient and elegant JSON library for Arduino.

scripts/publish.sh

@@ -0,0 +1,49 @@
+#!/usr/bin/env bash
+
+set -eu
+
+cd "$(dirname "$0")/.."
+
+VERSION="$1"
+DATE=$(date +%F)
+TAG="v$VERSION"
+
+update_version_in_source () {
+	IFS=".-" read MAJOR MINOR REVISION EXTRA < <(echo "$VERSION")
+	UNDERLINE=$(printf -- '-%.0s' $(seq 1 ${#TAG}))
+
+	sed -i~ -bE "4s/HEAD/$TAG ($DATE)/; 5s/-+/$UNDERLINE/" CHANGELOG.md
+	rm CHANGELOG.md*~
+	sed -i~ -bE "s/\"version\":.*$/\"version\": \"$VERSION\",/" library.json
+	rm library.json*~
+
+	sed -i~ -bE "s/version=.*$/version=$VERSION/" library.properties
+	rm library.properties*~
+
+	sed -i~ -bE \
+		-e "s/ARDUINOJSON_VERSION .*$/ARDUINOJSON_VERSION \"$VERSION\"/" \
+		-e "s/ARDUINOJSON_VERSION_MAJOR .*$/ARDUINOJSON_VERSION_MAJOR $MAJOR/" \
+		-e "s/ARDUINOJSON_VERSION_MINOR .*$/ARDUINOJSON_VERSION_MINOR $MINOR/" \
+		-e "s/ARDUINOJSON_VERSION_REVISION .*$/ARDUINOJSON_VERSION_REVISION $REVISION/" \
+		src/ArduinoJson/version.hpp
+	rm src/ArduinoJson/version.hpp*~
+}
+
+commit_new_version () {
+	git add src/ArduinoJson/version.hpp CHANGELOG.md library.json library.properties
+	git commit -m "Set version to $VERSION"
+}
+
+add_tag () {
+	CHANGES=$(awk '/\* /{ FOUND=1; print; next } { if (FOUND) exit}' CHANGELOG.md)
+	git tag -m "ArduinoJson $VERSION"$'\n'"$CHANGES" "$TAG"
+}
+
+push () {
+	git push --follow-tags
+}
+
+update_version_in_source
+commit_new_version
+add_tag
+push

scripts/travis/fuzz.sh

@@ -16,7 +16,7 @@ fuzz() {
 
 	export ASAN_OPTIONS="detect_leaks=0"
 	export LLVM_PROFILE_FILE="${FUZZER}.profraw"
-	./${FUZZER} "$CORPUS_DIR" "$SEED_CORPUS_DIR" -max_total_time=30
+	./${FUZZER} "$CORPUS_DIR" "$SEED_CORPUS_DIR" -max_total_time=30 -timeout=1
 
 	llvm-profdata-${CLANG} merge -sparse ${LLVM_PROFILE_FILE} -o ${FUZZER}.profdata
 	llvm-cov-${CLANG} report ./${FUZZER} -instr-profile=${FUZZER}.profdata

src/ArduinoJson.hpp

@@ -4,18 +4,17 @@
 
 #pragma once
 
-#include "ArduinoJson/version.hpp"
-
-#include "ArduinoJson/DynamicJsonDocument.hpp"
-#include "ArduinoJson/StaticJsonDocument.hpp"
-
-#include "ArduinoJson/JsonObjectImpl.hpp"
+#include "ArduinoJson/Namespace.hpp"
 
 #include "ArduinoJson/JsonArray.hpp"
+#include "ArduinoJson/JsonDocument.hpp"
 #include "ArduinoJson/JsonObject.hpp"
+#include "ArduinoJson/JsonVariant.hpp"
 
+#include "ArduinoJson/Data/VariantAsImpl.hpp"
 #include "ArduinoJson/JsonArrayImpl.hpp"
 #include "ArduinoJson/JsonArraySubscript.hpp"
+#include "ArduinoJson/JsonObjectImpl.hpp"
 #include "ArduinoJson/JsonObjectSubscript.hpp"
 #include "ArduinoJson/JsonVariantImpl.hpp"
 
@@ -24,3 +23,21 @@
 #include "ArduinoJson/Json/PrettyJsonSerializer.hpp"
 #include "ArduinoJson/MsgPack/MsgPackDeserializer.hpp"
 #include "ArduinoJson/MsgPack/MsgPackSerializer.hpp"
+
+namespace ArduinoJson {
+using ARDUINOJSON_NAMESPACE::DeserializationError;
+using ARDUINOJSON_NAMESPACE::DynamicJsonDocument;
+using ARDUINOJSON_NAMESPACE::JsonArray;
+using ARDUINOJSON_NAMESPACE::JsonArrayConst;
+using ARDUINOJSON_NAMESPACE::JsonFloat;
+using ARDUINOJSON_NAMESPACE::JsonInteger;
+using ARDUINOJSON_NAMESPACE::JsonKey;
+using ARDUINOJSON_NAMESPACE::JsonObject;
+using ARDUINOJSON_NAMESPACE::JsonObjectConst;
+using ARDUINOJSON_NAMESPACE::JsonPair;
+using ARDUINOJSON_NAMESPACE::JsonUInt;
+using ARDUINOJSON_NAMESPACE::JsonVariant;
+using ARDUINOJSON_NAMESPACE::JsonVariantConst;
+using ARDUINOJSON_NAMESPACE::serialized;
+using ARDUINOJSON_NAMESPACE::StaticJsonDocument;
+}  // namespace ArduinoJson

src/ArduinoJson/Configuration.hpp

@@ -4,6 +4,18 @@
 
 #pragma once
 
+#if defined(_MSC_VER)
+#define ARDUINOJSON_HAS_INT64 1
+#else
+#define ARDUINOJSON_HAS_INT64 0
+#endif
+
+#if __cplusplus >= 201103L
+#define ARDUINOJSON_HAS_LONG_LONG 1
+#else
+#define ARDUINOJSON_HAS_LONG_LONG 0
+#endif
+
 // Small or big machine?
 #ifndef ARDUINOJSON_EMBEDDED_MODE
 #if defined(ARDUINO) || defined(__IAR_SYSTEMS_ICC__) || defined(__XC) || \
@@ -25,9 +37,6 @@
 #ifndef ARDUINOJSON_USE_LONG_LONG
 #define ARDUINOJSON_USE_LONG_LONG 0
 #endif
-#ifndef ARDUINOJSON_USE_INT64
-#define ARDUINOJSON_USE_INT64 0
-#endif
 
 // Embedded systems usually don't have std::string
 #ifndef ARDUINOJSON_ENABLE_STD_STRING
@@ -44,6 +53,11 @@
 #define ARDUINOJSON_DEFAULT_NESTING_LIMIT 10
 #endif
 
+// Default capacity for DynamicJsonDocument
+#ifndef ARDUINOJSON_DEFAULT_POOL_SIZE
+#define ARDUINOJSON_DEFAULT_POOL_SIZE 1024
+#endif
+
 #else  // ARDUINOJSON_EMBEDDED_MODE
 
 // On a computer we have plenty of memory so we can use doubles
@@ -53,22 +67,13 @@
 
 // Use long long when available
 #ifndef ARDUINOJSON_USE_LONG_LONG
-#if __cplusplus >= 201103L || (defined(_MSC_VER) && _MSC_VER >= 1800)
+#if ARDUINOJSON_HAS_LONG_LONG || ARDUINOJSON_HAS_INT64
 #define ARDUINOJSON_USE_LONG_LONG 1
 #else
 #define ARDUINOJSON_USE_LONG_LONG 0
 #endif
 #endif
 
-// Use _int64 on old versions of Visual Studio
-#ifndef ARDUINOJSON_USE_INT64
-#if defined(_MSC_VER) && _MSC_VER <= 1700
-#define ARDUINOJSON_USE_INT64 1
-#else
-#define ARDUINOJSON_USE_INT64 0
-#endif
-#endif
-
 // On a computer, we can use std::string
 #ifndef ARDUINOJSON_ENABLE_STD_STRING
 #define ARDUINOJSON_ENABLE_STD_STRING 1
@@ -84,6 +89,11 @@
 #define ARDUINOJSON_DEFAULT_NESTING_LIMIT 50
 #endif
 
+// Default capacity for DynamicJsonDocument
+#ifndef ARDUINOJSON_DEFAULT_POOL_SIZE
+#define ARDUINOJSON_DEFAULT_POOL_SIZE 16384
+#endif
+
 #endif  // ARDUINOJSON_EMBEDDED_MODE
 
 #ifdef ARDUINO
@@ -120,16 +130,6 @@
 #endif
 #endif
 
-#ifndef ARDUINOJSON_ENABLE_ALIGNMENT
-#ifdef ARDUINO_ARCH_AVR
-// alignment isn't needed for 8-bit AVR
-#define ARDUINOJSON_ENABLE_ALIGNMENT 0
-#else
-// but most processors need pointers to be align on word size
-#define ARDUINOJSON_ENABLE_ALIGNMENT 1
-#endif
-#endif
-
 // Control the exponentiation threshold for big numbers
 // CAUTION: cannot be more that 1e9 !!!!
 #ifndef ARDUINOJSON_POSITIVE_EXPONENTIATION_THRESHOLD
@@ -141,10 +141,6 @@
 #define ARDUINOJSON_NEGATIVE_EXPONENTIATION_THRESHOLD 1e-5
 #endif
 
-#if ARDUINOJSON_USE_LONG_LONG && ARDUINOJSON_USE_INT64
-#error ARDUINOJSON_USE_LONG_LONG and ARDUINOJSON_USE_INT64 cannot be set together
-#endif
-
 #ifndef ARDUINOJSON_LITTLE_ENDIAN
 #if defined(_MSC_VER) ||                                                      \
     (defined(__BYTE_ORDER__) && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__) || \

src/ArduinoJson/Data/ArrayFunctions.hpp

@@ -0,0 +1,114 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2018
+// MIT License
+
+#pragma once
+
+#include "JsonVariantData.hpp"
+#include "SlotFunctions.hpp"
+
+namespace ARDUINOJSON_NAMESPACE {
+
+inline JsonVariantData* arrayAdd(JsonArrayData* arr, MemoryPool* pool) {
+  if (!arr) return 0;
+
+  VariantSlot* slot = pool->allocVariant();
+  if (!slot) return 0;
+
+  slot->next = 0;
+  slot->value.type = JSON_NULL;
+
+  if (arr->tail) {
+    slot->prev = arr->tail;
+    arr->tail->next = slot;
+    arr->tail = slot;
+  } else {
+    slot->prev = 0;
+    arr->head = slot;
+    arr->tail = slot;
+  }
+
+  slot->value.keyIsOwned = false;
+  return &slot->value;
+}
+
+inline VariantSlot* arrayGetSlot(const JsonArrayData* arr, size_t index) {
+  if (!arr) return 0;
+  return slotAdvance(arr->head, index);
+}
+
+inline JsonVariantData* arrayGet(const JsonArrayData* arr, size_t index) {
+  VariantSlot* slot = arrayGetSlot(arr, index);
+  return slot ? &slot->value : 0;
+}
+
+inline void arrayRemove(JsonArrayData* arr, VariantSlot* slot,
+                        MemoryPool* pool) {
+  if (!arr || !slot) return;
+
+  if (slot->prev)
+    slot->prev->next = slot->next;
+  else
+    arr->head = slot->next;
+  if (slot->next)
+    slot->next->prev = slot->prev;
+  else
+    arr->tail = slot->prev;
+
+  slotFree(slot, pool);
+}
+
+inline void arrayRemove(JsonArrayData* arr, size_t index, MemoryPool* pool) {
+  arrayRemove(arr, arrayGetSlot(arr, index), pool);
+}
+
+inline void arrayClear(JsonArrayData* arr) {
+  if (!arr) return;
+  arr->head = 0;
+  arr->tail = 0;
+}
+
+bool variantCopy(JsonVariantData*, const JsonVariantData*, MemoryPool*);
+
+inline bool arrayCopy(JsonArrayData* dst, const JsonArrayData* src,
+                      MemoryPool* pool) {
+  if (!dst || !src) return false;
+  arrayClear(dst);
+  for (VariantSlot* s = src->head; s; s = s->next) {
+    if (!variantCopy(arrayAdd(dst, pool), &s->value, pool)) return false;
+  }
+  return true;
+}
+
+bool variantEquals(const JsonVariantData*, const JsonVariantData*);
+
+inline bool arrayEquals(const JsonArrayData* a1, const JsonArrayData* a2) {
+  if (a1 == a2) return true;
+  if (!a1 || !a2) return false;
+  VariantSlot* s1 = a1->head;
+  VariantSlot* s2 = a2->head;
+  for (;;) {
+    if (s1 == s2) return true;
+    if (!s1 || !s2) return false;
+    if (!variantEquals(&s1->value, &s2->value)) return false;
+    s1 = s1->next;
+    s2 = s2->next;
+  }
+}
+
+inline size_t arraySize(const JsonArrayData* arr) {
+  if (!arr) return 0;
+  return slotSize(arr->head);
+}
+
+inline void arrayFree(JsonArrayData* arr, MemoryPool* pool) {
+  ARDUINOJSON_ASSERT(arr);
+
+  VariantSlot* cur = arr->head;
+  while (cur) {
+    VariantSlot* next = cur->next;
+    slotFree(cur, pool);
+    cur = next;
+  }
+}
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Data/IsVariant.hpp

@@ -1,17 +0,0 @@
-// ArduinoJson - arduinojson.org
-// Copyright Benoit Blanchon 2014-2018
-// MIT License
-
-#pragma once
-
-#include "../Polyfills/type_traits.hpp"
-
-namespace ArduinoJson {
-namespace Internals {
-
-class JsonVariantTag {};
-
-template <typename T>
-struct IsVariant : is_base_of<JsonVariantTag, T> {};
-}  // namespace Internals
-}  // namespace ArduinoJson

src/ArduinoJson/Data/JsonFloat.hpp

@@ -6,13 +6,11 @@
 
 #include "../Configuration.hpp"
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 #if ARDUINOJSON_USE_DOUBLE
 typedef double JsonFloat;
 #else
 typedef float JsonFloat;
 #endif
-}
-}
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Data/JsonInteger.hpp

@@ -6,18 +6,15 @@
 
 #include "../Configuration.hpp"
 
-namespace ArduinoJson {
-namespace Internals {
+#include <stdint.h>  // int64_t
+
+namespace ARDUINOJSON_NAMESPACE {
 
 #if ARDUINOJSON_USE_LONG_LONG
-typedef long long JsonInteger;
-typedef unsigned long long JsonUInt;
-#elif ARDUINOJSON_USE_INT64
-typedef __int64 JsonInteger;
-typedef unsigned _int64 JsonUInt;
+typedef int64_t JsonInteger;
+typedef uint64_t JsonUInt;
 #else
 typedef long JsonInteger;
 typedef unsigned long JsonUInt;
 #endif
-}
-}
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Data/JsonVariantAs.hpp

@@ -4,8 +4,14 @@
 
 #pragma once
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
+
+class JsonArray;
+class JsonArrayConst;
+class JsonObject;
+class JsonObjectConst;
+class JsonVariant;
+class JsonVariantConst;
 
 // A metafunction that returns the type of the value returned by
 // JsonVariant::as<T>()
@@ -19,5 +25,25 @@ struct JsonVariantAs<char*> {
   typedef const char* type;
 };
 
-}  // namespace Internals
-}  // namespace ArduinoJson
+// A metafunction that returns the type of the value returned by
+// JsonVariant::as<T>()
+template <typename T>
+struct JsonVariantConstAs {
+  typedef typename JsonVariantAs<T>::type type;
+};
+
+template <>
+struct JsonVariantConstAs<JsonVariant> {
+  typedef JsonVariantConst type;
+};
+
+template <>
+struct JsonVariantConstAs<JsonObject> {
+  typedef JsonObjectConst type;
+};
+
+template <>
+struct JsonVariantConstAs<JsonArray> {
+  typedef JsonArrayConst type;
+};
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Data/JsonVariantContent.hpp

@@ -1,30 +0,0 @@
-// ArduinoJson - arduinojson.org
-// Copyright Benoit Blanchon 2014-2018
-// MIT License
-
-#pragma once
-
-#include "JsonFloat.hpp"
-#include "JsonInteger.hpp"
-
-namespace ArduinoJson {
-namespace Internals {
-// Forward declarations
-struct JsonArrayData;
-struct JsonObjectData;
-
-// A union that defines the actual content of a JsonVariant.
-// The enum JsonVariantType determines which member is in use.
-union JsonVariantContent {
-  JsonFloat asFloat;         // used for double and float
-  JsonUInt asInteger;        // used for bool, char, short, int and longs
-  JsonArrayData* asArray;    // asArray cannot be null
-  JsonObjectData* asObject;  // asObject cannot be null
-  const char* asString;      // asString can be null
-  struct {
-    const char* data;
-    size_t size;
-  } asRaw;
-};
-}  // namespace Internals
-}  // namespace ArduinoJson

src/ArduinoJson/Data/JsonVariantData.hpp

@@ -0,0 +1,81 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2018
+// MIT License
+
+#pragma once
+
+#include <stddef.h>  // ptrdiff_t, size_t
+
+#include "JsonFloat.hpp"
+#include "JsonInteger.hpp"
+
+namespace ARDUINOJSON_NAMESPACE {
+
+enum JsonVariantType {
+  JSON_NULL,
+  JSON_LINKED_RAW,
+  JSON_OWNED_RAW,
+  JSON_LINKED_STRING,
+  JSON_OWNED_STRING,
+  JSON_BOOLEAN,
+  JSON_POSITIVE_INTEGER,
+  JSON_NEGATIVE_INTEGER,
+  JSON_ARRAY,
+  JSON_OBJECT,
+  JSON_FLOAT
+};
+
+struct JsonObjectData {
+  struct VariantSlot *head;
+  struct VariantSlot *tail;
+};
+
+struct JsonArrayData {
+  struct VariantSlot *head;
+  struct VariantSlot *tail;
+};
+
+struct RawData {
+  const char *data;
+  size_t size;
+};
+
+// A union that defines the actual content of a JsonVariantData.
+// The enum JsonVariantType determines which member is in use.
+union JsonVariantContent {
+  JsonFloat asFloat;
+  JsonUInt asInteger;
+  JsonArrayData asArray;
+  JsonObjectData asObject;
+  const char *asString;
+  struct StringSlot *asOwnedString;
+  struct StringSlot *asOwnedRaw;
+  struct {
+    const char *data;
+    size_t size;
+  } asRaw;
+};
+
+// this struct must be a POD type to prevent error calling offsetof on clang
+struct JsonVariantData {
+  bool keyIsOwned : 1;
+  JsonVariantType type : 7;
+  JsonVariantContent content;
+};
+
+inline JsonVariantData *getVariantData(JsonArrayData *arr) {
+  const ptrdiff_t offset = offsetof(JsonVariantData, content) -
+                           offsetof(JsonVariantContent, asArray);
+  if (!arr) return 0;
+  return reinterpret_cast<JsonVariantData *>(reinterpret_cast<char *>(arr) -
+                                             offset);
+}
+
+inline JsonVariantData *getVariantData(JsonObjectData *obj) {
+  const ptrdiff_t offset = offsetof(JsonVariantData, content) -
+                           offsetof(JsonVariantContent, asObject);
+  if (!obj) return 0;
+  return reinterpret_cast<JsonVariantData *>(reinterpret_cast<char *>(obj) -
+                                             offset);
+}
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Data/JsonVariantDefault.hpp

@@ -1,23 +0,0 @@
-// ArduinoJson - arduinojson.org
-// Copyright Benoit Blanchon 2014-2018
-// MIT License
-
-#pragma once
-
-namespace ArduinoJson {
-namespace Internals {
-
-template <typename T>
-struct JsonVariantDefault {
-  static T get() {
-    return T();
-  }
-};
-
-template <typename T>
-struct JsonVariantDefault<const T> : JsonVariantDefault<T> {};
-
-template <typename T>
-struct JsonVariantDefault<T&> : JsonVariantDefault<T> {};
-}
-}

src/ArduinoJson/Data/JsonVariantTo.hpp

@@ -0,0 +1,30 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2018
+// MIT License
+
+#pragma once
+
+namespace ARDUINOJSON_NAMESPACE {
+class JsonArray;
+class JsonObject;
+class JsonVariant;
+
+// A metafunction that returns the type of the value returned by
+// JsonVariant::to<T>()
+template <typename T>
+struct JsonVariantTo {};
+
+template <>
+struct JsonVariantTo<JsonArray> {
+  typedef JsonArray type;
+};
+template <>
+struct JsonVariantTo<JsonObject> {
+  typedef JsonObject type;
+};
+template <>
+struct JsonVariantTo<JsonVariant> {
+  typedef JsonVariant type;
+};
+
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Data/JsonVariantType.hpp

@@ -1,25 +0,0 @@
-// ArduinoJson - arduinojson.org
-// Copyright Benoit Blanchon 2014-2018
-// MIT License
-
-#pragma once
-
-namespace ArduinoJson {
-
-namespace Internals {
-
-// Enumerated type to know the current type of a JsonVariant.
-// The value determines which member of JsonVariantContent is used.
-enum JsonVariantType {
-  JSON_UNDEFINED,         // JsonVariant has not been initialized
-  JSON_UNPARSED,          // JsonVariant contains an unparsed string
-  JSON_STRING,            // JsonVariant stores a const char*
-  JSON_BOOLEAN,           // JsonVariant stores a bool
-  JSON_POSITIVE_INTEGER,  // JsonVariant stores an JsonUInt
-  JSON_NEGATIVE_INTEGER,  // JsonVariant stores an JsonUInt that must be negated
-  JSON_ARRAY,             // JsonVariant stores a pointer to a JsonArrayData
-  JSON_OBJECT,            // JsonVariant stores a pointer to a JsonObjectData
-  JSON_FLOAT              // JsonVariant stores a JsonFloat
-};
-}  // namespace Internals
-}  // namespace ArduinoJson

src/ArduinoJson/Data/List.hpp

@@ -1,88 +0,0 @@
-// ArduinoJson - arduinojson.org
-// Copyright Benoit Blanchon 2014-2018
-// MIT License
-
-#pragma once
-
-#include "../Memory/JsonBuffer.hpp"
-#include "ListConstIterator.hpp"
-#include "ListIterator.hpp"
-
-namespace ArduinoJson {
-namespace Internals {
-
-// A singly linked list of T.
-// The linked list is composed of ListNode<T>.
-// It is derived by JsonArrayData and JsonObjectData
-template <typename T>
-class List {
- public:
-  typedef T value_type;
-  typedef ListNode<T> node_type;
-  typedef ListIterator<T> iterator;
-  typedef ListConstIterator<T> const_iterator;
-
-  explicit List(JsonBuffer *buf) : _buffer(buf), _firstNode(NULL) {}
-
-  // Returns the numbers of elements in the list.
-  // For a JsonObjectData, it would return the number of key-value pairs
-  size_t size() const {
-    size_t nodeCount = 0;
-    for (node_type *node = _firstNode; node; node = node->next) nodeCount++;
-    return nodeCount;
-  }
-
-  iterator add() {
-    node_type *newNode = new (_buffer) node_type();
-
-    if (_firstNode) {
-      node_type *lastNode = _firstNode;
-      while (lastNode->next) lastNode = lastNode->next;
-      lastNode->next = newNode;
-    } else {
-      _firstNode = newNode;
-    }
-
-    return iterator(newNode);
-  }
-
-  iterator begin() {
-    return iterator(_firstNode);
-  }
-  iterator end() {
-    return iterator(NULL);
-  }
-
-  const_iterator begin() const {
-    return const_iterator(_firstNode);
-  }
-  const_iterator end() const {
-    return const_iterator(NULL);
-  }
-
-  void remove(iterator it) {
-    node_type *nodeToRemove = it._node;
-    if (!nodeToRemove) return;
-    if (nodeToRemove == _firstNode) {
-      _firstNode = nodeToRemove->next;
-    } else {
-      for (node_type *node = _firstNode; node; node = node->next)
-        if (node->next == nodeToRemove) node->next = nodeToRemove->next;
-    }
-  }
-
-  JsonBuffer &buffer() const {
-    return *_buffer;
-  }
-  JsonBuffer *_buffer;  // TODO!!
-
- protected:
-  void clear() {
-    _firstNode = 0;
-  }
-
- private:
-  node_type *_firstNode;
-};
-}  // namespace Internals
-}  // namespace ArduinoJson

src/ArduinoJson/Data/ListConstIterator.hpp

@@ -1,50 +0,0 @@
-// ArduinoJson - arduinojson.org
-// Copyright Benoit Blanchon 2014-2018
-// MIT License
-
-#pragma once
-
-#include "ListNode.hpp"
-
-namespace ArduinoJson {
-namespace Internals {
-
-// A read-only forward itertor for List<T>
-template <typename T>
-class ListConstIterator {
- public:
-  explicit ListConstIterator(const ListNode<T> *node = NULL) : _node(node) {}
-
-  const T &operator*() const {
-    return _node->content;
-  }
-  const T *operator->() {
-    return &_node->content;
-  }
-
-  bool operator==(const ListConstIterator<T> &other) const {
-    return _node == other._node;
-  }
-
-  bool operator!=(const ListConstIterator<T> &other) const {
-    return _node != other._node;
-  }
-
-  ListConstIterator<T> &operator++() {
-    if (_node) _node = _node->next;
-    return *this;
-  }
-
-  ListConstIterator<T> &operator+=(size_t distance) {
-    while (_node && distance) {
-      _node = _node->next;
-      --distance;
-    }
-    return *this;
-  }
-
- private:
-  const ListNode<T> *_node;
-};
-}
-}

src/ArduinoJson/Data/ListIterator.hpp

@@ -1,60 +0,0 @@
-// ArduinoJson - arduinojson.org
-// Copyright Benoit Blanchon 2014-2018
-// MIT License
-
-#pragma once
-
-#include "ListConstIterator.hpp"
-#include "ListNode.hpp"
-
-namespace ArduinoJson {
-namespace Internals {
-
-template <typename T>
-class List;
-
-// A read-write forward iterator for List<T>
-template <typename T>
-class ListIterator {
-  friend class List<T>;
-
- public:
-  explicit ListIterator(ListNode<T> *node = NULL) : _node(node) {}
-
-  T &operator*() const {
-    return _node->content;
-  }
-  T *operator->() {
-    return &_node->content;
-  }
-
-  bool operator==(const ListIterator<T> &other) const {
-    return _node == other._node;
-  }
-
-  bool operator!=(const ListIterator<T> &other) const {
-    return _node != other._node;
-  }
-
-  ListIterator<T> &operator++() {
-    if (_node) _node = _node->next;
-    return *this;
-  }
-
-  ListIterator<T> &operator+=(size_t distance) {
-    while (_node && distance) {
-      _node = _node->next;
-      --distance;
-    }
-    return *this;
-  }
-
-  operator ListConstIterator<T>() const {
-    return ListConstIterator<T>(_node);
-  }
-
- private:
-  ListNode<T> *_node;
-};
-}
-}

src/ArduinoJson/Data/ListNode.hpp

@@ -1,24 +0,0 @@
-// ArduinoJson - arduinojson.org
-// Copyright Benoit Blanchon 2014-2018
-// MIT License
-
-#pragma once
-
-#include <stddef.h>  // for NULL
-
-#include "../Memory/JsonBufferAllocated.hpp"
-
-namespace ArduinoJson {
-namespace Internals {
-
-// A node for a singly-linked list.
-// Used by List<T> and its iterators.
-template <typename T>
-struct ListNode : public Internals::JsonBufferAllocated {
-  ListNode() throw() : next(NULL) {}
-
-  ListNode<T> *next;
-  T content;
-};
-}  // namespace Internals
-}  // namespace ArduinoJson

src/ArduinoJson/Data/ObjectFunctions.hpp

@@ -0,0 +1,128 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2018
+// MIT License
+
+#pragma once
+
+#include "../Memory/MemoryPool.hpp"
+#include "JsonVariantData.hpp"
+#include "SlotFunctions.hpp"
+
+namespace ARDUINOJSON_NAMESPACE {
+
+template <typename TKey>
+inline VariantSlot* objectFindSlot(const JsonObjectData* obj, TKey key) {
+  if (!obj) return 0;
+  VariantSlot* slot = obj->head;
+  while (slot) {
+    if (key.equals(slotGetKey(slot))) break;
+    slot = slot->next;
+  }
+  return slot;
+}
+
+template <typename TKey>
+inline bool objectContainsKey(const JsonObjectData* obj, const TKey& key) {
+  return objectFindSlot(obj, key) != 0;
+}
+
+template <typename TKey>
+inline JsonVariantData* objectAdd(JsonObjectData* obj, TKey key,
+                                  MemoryPool* pool) {
+  VariantSlot* slot = pool->allocVariant();
+  if (!slot) return 0;
+
+  slot->next = 0;
+  slot->value.type = JSON_NULL;
+
+  if (obj->tail) {
+    slot->prev = obj->tail;
+    obj->tail->next = slot;
+    obj->tail = slot;
+  } else {
+    slot->prev = 0;
+    obj->head = slot;
+    obj->tail = slot;
+  }
+
+  if (!slotSetKey(slot, key, pool)) return 0;
+  return &slot->value;
+}
+
+template <typename TKey>
+inline JsonVariantData* objectSet(JsonObjectData* obj, TKey key,
+                                  MemoryPool* pool) {
+  if (!obj) return 0;
+
+  // ignore null key
+  if (key.isNull()) return 0;
+
+  // search a matching key
+  VariantSlot* slot = objectFindSlot(obj, key);
+  if (slot) return &slot->value;
+
+  return objectAdd(obj, key, pool);
+}
+
+template <typename TKey>
+inline JsonVariantData* objectGet(const JsonObjectData* obj, TKey key) {
+  VariantSlot* slot = objectFindSlot(obj, key);
+  return slot ? &slot->value : 0;
+}
+
+inline void objectClear(JsonObjectData* obj) {
+  if (!obj) return;
+  obj->head = 0;
+  obj->tail = 0;
+}
+
+inline void objectRemove(JsonObjectData* obj, VariantSlot* slot,
+                         MemoryPool* pool) {
+  if (!obj) return;
+  if (!slot) return;
+  if (slot->prev)
+    slot->prev->next = slot->next;
+  else
+    obj->head = slot->next;
+  if (slot->next)
+    slot->next->prev = slot->prev;
+  else
+    obj->tail = slot->prev;
+
+  slotFree(slot, pool);
+}
+
+inline size_t objectSize(const JsonObjectData* obj) {
+  if (!obj) return 0;
+  return slotSize(obj->head);
+}
+
+// bool variantCopy(JsonVariantData*, const JsonVariantData*, MemoryPool*);
+
+inline bool objectCopy(JsonObjectData* dst, const JsonObjectData* src,
+                       MemoryPool* pool) {
+  if (!dst || !src) return false;
+  objectClear(dst);
+  for (VariantSlot* s = src->head; s; s = s->next) {
+    JsonVariantData* var;
+    if (s->value.keyIsOwned)
+      var = objectAdd(dst, ZeroTerminatedRamString(s->ownedKey->value), pool);
+    else
+      var = objectAdd(dst, ZeroTerminatedRamStringConst(s->linkedKey), pool);
+    if (!variantCopy(var, &s->value, pool)) return false;
+  }
+  return true;
+}
+
+inline bool objectEquals(const JsonObjectData* o1, const JsonObjectData* o2) {
+  if (o1 == o2) return true;
+  if (!o1 || !o2) return false;
+
+  for (VariantSlot* s = o1->head; s; s = s->next) {
+    JsonVariantData* v1 = &s->value;
+    JsonVariantData* v2 = objectGet(o2, makeString(slotGetKey(s)));
+    if (!variantEquals(v1, v2)) return false;
+  }
+  return true;
+}
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Data/SlotFunctions.hpp

@@ -0,0 +1,77 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2018
+// MIT License
+
+#pragma once
+
+#include "../Memory/MemoryPool.hpp"
+#include "../Polyfills/assert.hpp"
+#include "../Strings/StringTypes.hpp"
+#include "JsonVariantData.hpp"
+
+namespace ARDUINOJSON_NAMESPACE {
+
+template <typename TKey>
+inline bool slotSetKey(VariantSlot* var, TKey key, MemoryPool* pool) {
+  StringSlot* slot = key.save(pool);
+  if (!slot) return false;
+  var->ownedKey = slot;
+  var->value.keyIsOwned = true;
+  return true;
+}
+
+inline bool slotSetKey(VariantSlot* var, ZeroTerminatedRamStringConst key,
+                       MemoryPool*) {
+  var->linkedKey = key.c_str();
+  var->value.keyIsOwned = false;
+  return true;
+}
+
+inline bool slotSetKey(VariantSlot* var, StringInMemoryPool key, MemoryPool*) {
+  var->ownedKey = key.slot();
+  var->value.keyIsOwned = true;
+  return true;
+}
+
+inline const char* slotGetKey(const VariantSlot* var) {
+  return var->value.keyIsOwned ? var->ownedKey->value : var->linkedKey;
+}
+
+inline const VariantSlot* slotAdvance(const VariantSlot* var, size_t distance) {
+  while (distance && var) {
+    var = var->next;
+    distance--;
+  }
+  return var;
+}
+
+inline VariantSlot* slotAdvance(VariantSlot* var, size_t distance) {
+  while (distance && var) {
+    var = var->next;
+    distance--;
+  }
+  return var;
+}
+
+inline size_t slotSize(const VariantSlot* var) {
+  size_t n = 0;
+  while (var) {
+    n++;
+    var = var->next;
+  }
+  return n;
+}
+
+void variantFree(JsonVariantData* var, MemoryPool* pool);
+
+inline void slotFree(VariantSlot* var, MemoryPool* pool) {
+  ARDUINOJSON_ASSERT(var != 0);
+  ARDUINOJSON_ASSERT(pool != 0);
+
+  variantFree(&var->value, pool);
+
+  if (var->value.keyIsOwned) pool->freeString(var->ownedKey);
+
+  pool->freeVariant(var);
+}
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Data/ValueSaver.hpp

@@ -1,53 +0,0 @@
-// ArduinoJson - arduinojson.org
-// Copyright Benoit Blanchon 2014-2018
-// MIT License
-
-#pragma once
-
-#include "../JsonVariant.hpp"
-#include "../Memory/JsonBuffer.hpp"
-#include "../Polyfills/type_traits.hpp"
-#include "../Strings/StringTypes.hpp"
-
-namespace ArduinoJson {
-namespace Internals {
-
-template <typename Source, typename Enable = void>
-struct ValueSaver {
-  template <typename Destination>
-  static bool save(JsonBuffer*, Destination& destination, Source source) {
-    destination = source;
-    return true;
-  }
-};
-
-// We duplicate all strings except const char*
-template <typename TString>
-struct ValueSaver<
-    TString, typename enable_if<IsString<TString>::value &&
-                                !is_same<const char*, TString>::value>::type> {
-  template <typename Destination>
-  static bool save(JsonBuffer* buffer, Destination& dest, TString source) {
-    const char* dup = makeString(source).save(buffer);
-    if (!dup) return false;
-    dest = dup;
-    return true;
-  }
-};
-
-// We duplicate all SerializedValue<T> except SerializedValue<const char*>
-template <typename TString>
-struct ValueSaver<
-    const SerializedValue<TString>&,
-    typename enable_if<!is_same<const char*, TString>::value>::type> {
-  template <typename Destination>
-  static bool save(JsonBuffer* buffer, Destination& dest,
-                   const SerializedValue<TString>& source) {
-    const char* dup = makeString(source.data(), source.size()).save(buffer);
-    if (!dup) return false;
-    dest = SerializedValue<const char*>(dup, source.size());
-    return true;
-  }
-};
-}  // namespace Internals
-}  // namespace ArduinoJson

src/ArduinoJson/Data/VariantAs.hpp

@@ -0,0 +1,48 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2018
+// MIT License
+
+#pragma once
+
+#include "../Serialization/DynamicStringWriter.hpp"
+#include "VariantFunctions.hpp"
+
+namespace ARDUINOJSON_NAMESPACE {
+
+class JsonVariantConst;
+
+template <typename T>
+inline typename enable_if<is_integral<T>::value, T>::type variantAs(
+    const JsonVariantData* _data) {
+  return variantAsIntegral<T>(_data);
+}
+
+template <typename T>
+inline typename enable_if<is_same<T, bool>::value, T>::type variantAs(
+    const JsonVariantData* _data) {
+  return variantAsBoolean(_data);
+}
+
+template <typename T>
+inline typename enable_if<is_floating_point<T>::value, T>::type variantAs(
+    const JsonVariantData* _data) {
+  return variantAsFloat<T>(_data);
+}
+
+template <typename T>
+inline typename enable_if<is_same<T, const char*>::value ||
+                              is_same<T, char*>::value,
+                          const char*>::type
+variantAs(const JsonVariantData* _data) {
+  return variantAsString(_data);
+}
+
+template <typename T>
+inline typename enable_if<is_same<JsonVariantConst, T>::value, T>::type
+variantAs(const JsonVariantData* _data);
+
+template <typename T>
+inline typename enable_if<IsWriteableString<T>::value, T>::type variantAs(
+    const JsonVariantData* _data);
+
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Data/VariantAsImpl.hpp

@@ -0,0 +1,29 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2018
+// MIT License
+
+#pragma once
+
+#include "../JsonVariant.hpp"
+#include "../Serialization/DynamicStringWriter.hpp"
+#include "VariantFunctions.hpp"
+
+namespace ARDUINOJSON_NAMESPACE {
+
+template <typename T>
+inline typename enable_if<is_same<JsonVariantConst, T>::value, T>::type
+variantAs(const JsonVariantData* _data) {
+  return JsonVariantConst(_data);
+}
+
+template <typename T>
+inline typename enable_if<IsWriteableString<T>::value, T>::type variantAs(
+    const JsonVariantData* _data) {
+  const char* cstr = variantAsString(_data);
+  if (cstr) return T(cstr);
+  T s;
+  serializeJson(JsonVariantConst(_data), s);
+  return s;
+}
+
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Data/VariantFunctions.hpp

@@ -0,0 +1,341 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2018
+// MIT License
+
+#pragma once
+
+#include "../Numbers/parseFloat.hpp"
+#include "../Numbers/parseInteger.hpp"
+#include "../SerializedValue.hpp"
+#include "ArrayFunctions.hpp"
+#include "JsonVariantData.hpp"
+#include "ObjectFunctions.hpp"
+
+namespace ARDUINOJSON_NAMESPACE {
+
+inline void variantFree(JsonVariantData* var, MemoryPool* pool) {
+  ARDUINOJSON_ASSERT(var != 0);
+  ARDUINOJSON_ASSERT(pool != 0);
+
+  switch (var->type) {
+    case JSON_ARRAY:
+    case JSON_OBJECT:
+      arrayFree(&var->content.asArray, pool);
+      break;
+    case JSON_OWNED_STRING:
+    case JSON_OWNED_RAW:
+      pool->freeString(var->content.asOwnedString);
+      break;
+    default:
+      break;
+  }
+}
+
+template <typename T>
+inline T variantAsIntegral(const JsonVariantData* var) {
+  if (!var) return 0;
+  switch (var->type) {
+    case JSON_POSITIVE_INTEGER:
+    case JSON_BOOLEAN:
+      return T(var->content.asInteger);
+    case JSON_NEGATIVE_INTEGER:
+      return T(~var->content.asInteger + 1);
+    case JSON_LINKED_STRING:
+      return parseInteger<T>(var->content.asString);
+    case JSON_OWNED_STRING:
+      return parseInteger<T>(var->content.asOwnedString->value);
+    case JSON_FLOAT:
+      return T(var->content.asFloat);
+    default:
+      return 0;
+  }
+}
+
+inline bool variantAsBoolean(const JsonVariantData* var) {
+  return variantAsIntegral<int>(var) != 0;
+}
+
+// T = float/double
+template <typename T>
+inline T variantAsFloat(const JsonVariantData* var) {
+  if (!var) return 0;
+  switch (var->type) {
+    case JSON_POSITIVE_INTEGER:
+    case JSON_BOOLEAN:
+      return static_cast<T>(var->content.asInteger);
+    case JSON_NEGATIVE_INTEGER:
+      return -static_cast<T>(var->content.asInteger);
+    case JSON_LINKED_STRING:
+      return parseFloat<T>(var->content.asString);
+    case JSON_OWNED_STRING:
+      return parseFloat<T>(var->content.asOwnedString->value);
+    case JSON_FLOAT:
+      return static_cast<T>(var->content.asFloat);
+    default:
+      return 0;
+  }
+}
+
+inline const char* variantAsString(const JsonVariantData* var) {
+  if (!var) return 0;
+  switch (var->type) {
+    case JSON_LINKED_STRING:
+      return var->content.asString;
+    case JSON_OWNED_STRING:
+      return var->content.asOwnedString->value;
+    default:
+      return 0;
+  }
+}
+
+inline JsonArrayData* variantAsArray(JsonVariantData* var) {
+  if (var && var->type == JSON_ARRAY)
+    return &var->content.asArray;
+  else
+    return 0;
+}
+
+inline const JsonArrayData* variantAsArray(const JsonVariantData* var) {
+  if (var && var->type == JSON_ARRAY)
+    return &var->content.asArray;
+  else
+    return 0;
+}
+
+inline JsonObjectData* variantAsObject(JsonVariantData* var) {
+  if (var && var->type == JSON_OBJECT)
+    return &var->content.asObject;
+  else
+    return 0;
+}
+
+inline const JsonObjectData* variantAsObject(const JsonVariantData* var) {
+  if (var && var->type == JSON_OBJECT)
+    return &var->content.asObject;
+  else
+    return 0;
+}
+
+inline bool variantSetBoolean(JsonVariantData* var, bool value,
+                              MemoryPool* pool) {
+  if (!var) return false;
+  variantFree(var, pool);
+  var->type = JSON_BOOLEAN;
+  var->content.asInteger = static_cast<JsonUInt>(value);
+  return true;
+}
+
+inline bool variantSetFloat(JsonVariantData* var, JsonFloat value,
+                            MemoryPool* pool) {
+  if (!var) return false;
+  variantFree(var, pool);
+  var->type = JSON_FLOAT;
+  var->content.asFloat = value;
+  return true;
+}
+
+template <typename T>
+inline bool variantSetSignedInteger(JsonVariantData* var, T value,
+                                    MemoryPool* pool) {
+  if (!var) return false;
+  variantFree(var, pool);
+
+  if (value >= 0) {
+    var->type = JSON_POSITIVE_INTEGER;
+    var->content.asInteger = static_cast<JsonUInt>(value);
+  } else {
+    var->type = JSON_NEGATIVE_INTEGER;
+    var->content.asInteger = ~static_cast<JsonUInt>(value) + 1;
+  }
+  return true;
+}
+
+inline bool variantSetUnsignedInteger(JsonVariantData* var, JsonUInt value,
+                                      MemoryPool* pool) {
+  if (!var) return false;
+  variantFree(var, pool);
+  var->type = JSON_POSITIVE_INTEGER;
+  var->content.asInteger = static_cast<JsonUInt>(value);
+  return true;
+}
+
+inline bool variantSetLinkedRaw(JsonVariantData* var,
+                                SerializedValue<const char*> value,
+                                MemoryPool* pool) {
+  if (!var) return false;
+  variantFree(var, pool);
+  var->type = JSON_LINKED_RAW;
+  var->content.asRaw.data = value.data();
+  var->content.asRaw.size = value.size();
+  return true;
+}
+
+template <typename T>
+inline bool variantSetOwnedRaw(JsonVariantData* var, SerializedValue<T> value,
+                               MemoryPool* pool) {
+  if (!var) return false;
+  variantFree(var, pool);
+  StringSlot* slot = makeString(value.data(), value.size()).save(pool);
+  if (slot) {
+    var->type = JSON_OWNED_RAW;
+    var->content.asOwnedRaw = slot;
+    return true;
+  } else {
+    var->type = JSON_NULL;
+    return false;
+  }
+}
+
+template <typename T>
+inline bool variantSetString(JsonVariantData* var, T value, MemoryPool* pool) {
+  if (!var) return false;
+  variantFree(var, pool);
+  StringSlot* slot = value.save(pool);
+  if (slot) {
+    var->type = JSON_OWNED_STRING;
+    var->content.asOwnedString = slot;
+    return true;
+  } else {
+    var->type = JSON_NULL;
+    return false;
+  }
+}
+
+inline bool variantSetOwnedString(JsonVariantData* var, StringSlot* slot,
+                                  MemoryPool* pool) {
+  if (!var) return false;
+  variantFree(var, pool);
+  var->type = JSON_OWNED_STRING;
+  var->content.asOwnedString = slot;
+  return true;
+}
+
+inline bool variantSetString(JsonVariantData* var, const char* value,
+                             MemoryPool* pool) {
+  if (!var) return false;
+  variantFree(var, pool);
+  var->type = JSON_LINKED_STRING;
+  var->content.asString = value;
+  return true;
+}
+
+inline void variantSetNull(JsonVariantData* var, MemoryPool* pool) {
+  if (!var) return;
+  variantFree(var, pool);
+  var->type = JSON_NULL;
+}
+
+inline JsonArrayData* variantToArray(JsonVariantData* var, MemoryPool* pool) {
+  if (!var) return 0;
+  variantFree(var, pool);
+  var->type = JSON_ARRAY;
+  var->content.asArray.head = 0;
+  var->content.asArray.tail = 0;
+  return &var->content.asArray;
+}
+
+inline JsonObjectData* variantToObject(JsonVariantData* var, MemoryPool* pool) {
+  if (!var) return 0;
+  variantFree(var, pool);
+  var->type = JSON_OBJECT;
+  var->content.asObject.head = 0;
+  var->content.asObject.tail = 0;
+  return &var->content.asObject;
+}
+
+inline bool variantCopy(JsonVariantData* dst, const JsonVariantData* src,
+                        MemoryPool* pool) {
+  if (!dst) return false;
+  if (!src) {
+    variantFree(dst, pool);
+    dst->type = JSON_NULL;
+    return true;
+  }
+  switch (src->type) {
+    case JSON_ARRAY:
+      return arrayCopy(variantToArray(dst, pool), &src->content.asArray, pool);
+    case JSON_OBJECT:
+      return objectCopy(variantToObject(dst, pool), &src->content.asObject,
+                        pool);
+    case JSON_OWNED_STRING:
+      return variantSetString(
+          dst, makeString(src->content.asOwnedString->value), pool);
+    case JSON_OWNED_RAW:
+      return variantSetOwnedRaw(dst,
+                                serialized(src->content.asOwnedRaw->value,
+                                           src->content.asOwnedRaw->size),
+                                pool);
+    default:
+      variantFree(dst, pool);
+      // caution: don't override keyIsOwned
+      dst->type = src->type;
+      dst->content = src->content;
+      return true;
+  }
+}
+
+inline bool variantIsInteger(const JsonVariantData* var) {
+  return var && (var->type == JSON_POSITIVE_INTEGER ||
+                 var->type == JSON_NEGATIVE_INTEGER);
+}
+
+inline bool variantIsFloat(const JsonVariantData* var) {
+  return var &&
+         (var->type == JSON_FLOAT || var->type == JSON_POSITIVE_INTEGER ||
+          var->type == JSON_NEGATIVE_INTEGER);
+}
+
+inline bool variantIsString(const JsonVariantData* var) {
+  return var &&
+         (var->type == JSON_LINKED_STRING || var->type == JSON_OWNED_STRING);
+}
+
+inline bool variantIsArray(const JsonVariantData* var) {
+  return var && var->type == JSON_ARRAY;
+}
+
+inline bool variantIsObject(const JsonVariantData* var) {
+  return var && var->type == JSON_OBJECT;
+}
+
+inline bool variantIsNull(const JsonVariantData* var) {
+  return var == 0 || var->type == JSON_NULL;
+}
+
+inline bool variantEquals(const JsonVariantData* a, const JsonVariantData* b) {
+  if (a == b) return true;
+  if (!a || !b) return false;
+  if (a->type != b->type) return false;
+
+  switch (a->type) {
+    case JSON_LINKED_RAW:
+    case JSON_LINKED_STRING:
+      return !strcmp(a->content.asString, b->content.asString);
+
+    case JSON_OWNED_RAW:
+    case JSON_OWNED_STRING:
+      return a->content.asOwnedString->size == b->content.asOwnedString->size &&
+             !memcmp(a->content.asOwnedString->value,
+                     b->content.asOwnedString->value,
+                     a->content.asOwnedString->size);
+
+    case JSON_BOOLEAN:
+    case JSON_POSITIVE_INTEGER:
+    case JSON_NEGATIVE_INTEGER:
+      return a->content.asInteger == b->content.asInteger;
+
+    case JSON_ARRAY:
+      return arrayEquals(&a->content.asArray, &b->content.asArray);
+
+    case JSON_OBJECT:
+      return objectEquals(&a->content.asObject, &b->content.asObject);
+
+    case JSON_FLOAT:
+      return a->content.asFloat == b->content.asFloat;
+
+    case JSON_NULL:
+    default:
+      return true;
+  }
+}
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Deserialization/ArduinoStreamReader.hpp

@@ -8,8 +8,7 @@
 
 #include <Stream.h>
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 struct ArduinoStreamReader {
   Stream& _stream;
@@ -35,7 +34,6 @@ struct ArduinoStreamReader {
 inline ArduinoStreamReader makeReader(Stream& input) {
   return ArduinoStreamReader(input);
 }
-}  // namespace Internals
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE
 
 #endif

src/ArduinoJson/Deserialization/CharPointerReader.hpp

@@ -4,8 +4,7 @@
 
 #pragma once
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 template <typename TChar>
 class UnsafeCharPointerReader {
@@ -60,5 +59,4 @@ inline SafeCharPointerReader<char> makeReader(const String& input) {
 }
 #endif
 
-}  // namespace Internals
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Deserialization/DeserializationError.hpp

@@ -8,9 +8,13 @@
 #include <ostream>
 #endif
 
-namespace ArduinoJson {
+namespace ARDUINOJSON_NAMESPACE {
 
 class DeserializationError {
+  // safe bool idiom
+  typedef void (DeserializationError::*bool_type)() const;
+  void safeBoolHelper() const {}
+
  public:
   enum Code {
     Ok,
@@ -22,26 +26,52 @@ class DeserializationError {
   };
 
   DeserializationError() {}
-  DeserializationError(Code code) : _code(code) {}
+  DeserializationError(Code c) : _code(c) {}
 
-  friend bool operator==(const DeserializationError& err, Code code) {
-    return err._code == code;
+  // Compare with DeserializationError
+  friend bool operator==(const DeserializationError& lhs,
+                         const DeserializationError& rhs) {
+    return lhs._code == rhs._code;
+  }
+  friend bool operator!=(const DeserializationError& lhs,
+                         const DeserializationError& rhs) {
+    return lhs._code != rhs._code;
   }
 
-  friend bool operator==(Code code, const DeserializationError& err) {
-    return err._code == code;
+  // Compare with Code
+  friend bool operator==(const DeserializationError& lhs, Code rhs) {
+    return lhs._code == rhs;
+  }
+  friend bool operator==(Code lhs, const DeserializationError& rhs) {
+    return lhs == rhs._code;
+  }
+  friend bool operator!=(const DeserializationError& lhs, Code rhs) {
+    return lhs._code != rhs;
+  }
+  friend bool operator!=(Code lhs, const DeserializationError& rhs) {
+    return lhs != rhs._code;
   }
 
-  friend bool operator!=(const DeserializationError& err, Code code) {
-    return err._code != code;
+  // Behaves like a bool
+  operator bool_type() const {
+    return _code != Ok ? &DeserializationError::safeBoolHelper : 0;
+  }
+  friend bool operator==(bool value, const DeserializationError& err) {
+    return static_cast<bool>(err) == value;
+  }
+  friend bool operator==(const DeserializationError& err, bool value) {
+    return static_cast<bool>(err) == value;
+  }
+  friend bool operator!=(bool value, const DeserializationError& err) {
+    return static_cast<bool>(err) != value;
+  }
+  friend bool operator!=(const DeserializationError& err, bool value) {
+    return static_cast<bool>(err) != value;
   }
 
-  friend bool operator!=(Code code, const DeserializationError& err) {
-    return err._code != code;
-  }
-
-  operator bool() const {
-    return _code != Ok;
+  // Returns internal enum, useful for switch statement
+  Code code() const {
+    return _code;
   }
 
   const char* c_str() const {
@@ -80,4 +110,4 @@ inline std::ostream& operator<<(std::ostream& s, DeserializationError::Code c) {
 }
 #endif
 
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Deserialization/FlashStringReader.hpp

@@ -6,8 +6,7 @@
 
 #if ARDUINOJSON_ENABLE_PROGMEM
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 class UnsafeFlashStringReader {
   const char* _ptr;
 
@@ -50,7 +49,6 @@ inline SafeFlashStringReader makeReader(const __FlashStringHelper* input,
                                         size_t size) {
   return SafeFlashStringReader(input, size);
 }
-}  // namespace Internals
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE
 
 #endif

src/ArduinoJson/Deserialization/IteratorReader.hpp

@@ -4,8 +4,7 @@
 
 #pragma once
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 template <typename TIterator>
 class IteratorReader {
@@ -30,5 +29,4 @@ inline IteratorReader<typename TInput::const_iterator> makeReader(
   return IteratorReader<typename TInput::const_iterator>(input.begin(),
                                                          input.end());
 }
-}  // namespace Internals
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Deserialization/StdStreamReader.hpp

@@ -8,8 +8,7 @@
 
 #include <istream>
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 class StdStreamReader {
   std::istream& _stream;
@@ -34,7 +33,6 @@ class StdStreamReader {
 inline StdStreamReader makeReader(std::istream& input) {
   return StdStreamReader(input);
 }
-}  // namespace Internals
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE
 
 #endif

src/ArduinoJson/Deserialization/deserialize.hpp

@@ -12,15 +12,15 @@
 #include "./IteratorReader.hpp"
 #include "./StdStreamReader.hpp"
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 template <template <typename, typename> class TDeserializer,
-          typename TJsonBuffer, typename TReader, typename TWriter>
-TDeserializer<TReader, TWriter> makeDeserializer(TJsonBuffer *buffer,
+          typename TMemoryPool, typename TReader, typename TWriter>
+TDeserializer<TReader, TWriter> makeDeserializer(TMemoryPool &memoryPool,
                                                  TReader reader, TWriter writer,
                                                  uint8_t nestingLimit) {
-  return TDeserializer<TReader, TWriter>(buffer, reader, writer, nestingLimit);
+  return TDeserializer<TReader, TWriter>(memoryPool, reader, writer,
+                                         nestingLimit);
 }
 
 // DeserializationError deserialize(TDocument& doc, TString input);
@@ -28,13 +28,11 @@ TDeserializer<TReader, TWriter> makeDeserializer(TJsonBuffer *buffer,
 // TString = const std::string&, const String&
 template <template <typename, typename> class TDeserializer, typename TDocument,
           typename TString>
-typename Internals::enable_if<!Internals::is_array<TString>::value,
-                              DeserializationError>::type
+typename enable_if<!is_array<TString>::value, DeserializationError>::type
 deserialize(TDocument &doc, const TString &input) {
-  using namespace Internals;
-  return makeDeserializer<TDeserializer>(&doc.buffer(), makeReader(input),
-                                         makeStringStorage(doc.buffer(), input),
-                                         doc.nestingLimit)
+  return makeDeserializer<TDeserializer>(
+             doc.memoryPool(), makeReader(input),
+             makeStringStorage(doc.memoryPool(), input), doc.nestingLimit)
       .parse(doc.template to<JsonVariant>());
 }
 //
@@ -44,10 +42,9 @@ deserialize(TDocument &doc, const TString &input) {
 template <template <typename, typename> class TDeserializer, typename TDocument,
           typename TChar>
 DeserializationError deserialize(TDocument &doc, TChar *input) {
-  using namespace Internals;
-  return makeDeserializer<TDeserializer>(&doc.buffer(), makeReader(input),
-                                         makeStringStorage(doc.buffer(), input),
-                                         doc.nestingLimit)
+  return makeDeserializer<TDeserializer>(
+             doc.memoryPool(), makeReader(input),
+             makeStringStorage(doc.memoryPool(), input), doc.nestingLimit)
       .parse(doc.template to<JsonVariant>());
 }
 //
@@ -59,10 +56,9 @@ template <template <typename, typename> class TDeserializer, typename TDocument,
           typename TChar>
 DeserializationError deserialize(TDocument &doc, TChar *input,
                                  size_t inputSize) {
-  using namespace Internals;
   return makeDeserializer<TDeserializer>(
-             &doc.buffer(), makeReader(input, inputSize),
-             makeStringStorage(doc.buffer(), input), doc.nestingLimit)
+             doc.memoryPool(), makeReader(input, inputSize),
+             makeStringStorage(doc.memoryPool(), input), doc.nestingLimit)
       .parse(doc.template to<JsonVariant>());
 }
 //
@@ -72,11 +68,9 @@ DeserializationError deserialize(TDocument &doc, TChar *input,
 template <template <typename, typename> class TDeserializer, typename TDocument,
           typename TStream>
 DeserializationError deserialize(TDocument &doc, TStream &input) {
-  using namespace Internals;
-  return makeDeserializer<TDeserializer>(&doc.buffer(), makeReader(input),
-                                         makeStringStorage(doc.buffer(), input),
-                                         doc.nestingLimit)
+  return makeDeserializer<TDeserializer>(
+             doc.memoryPool(), makeReader(input),
+             makeStringStorage(doc.memoryPool(), input), doc.nestingLimit)
       .parse(doc.template to<JsonVariant>());
 }
-}  // namespace Internals
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/DynamicJsonDocument.hpp

@@ -1,84 +0,0 @@
-// ArduinoJson - arduinojson.org
-// Copyright Benoit Blanchon 2014-2018
-// MIT License
-
-#pragma once
-
-#include "JsonArray.hpp"
-#include "JsonObject.hpp"
-#include "JsonVariant.hpp"
-#include "Memory/DynamicJsonBuffer.hpp"
-
-namespace ArduinoJson {
-
-class DynamicJsonDocument {
-  Internals::DynamicJsonBuffer _buffer;
-  JsonVariant _root;
-
- public:
-  uint8_t nestingLimit;
-
-  DynamicJsonDocument() : nestingLimit(ARDUINOJSON_DEFAULT_NESTING_LIMIT) {}
-  DynamicJsonDocument(size_t capacity)
-      : _buffer(capacity), nestingLimit(ARDUINOJSON_DEFAULT_NESTING_LIMIT) {}
-
-  template <typename T>
-  bool is() const {
-    return _root.is<T>();
-  }
-
-  template <typename T>
-  typename Internals::JsonVariantAs<T>::type as() const {
-    return _root.as<T>();
-  }
-
-  // JsonObject to<JsonObject>()
-  template <typename T>
-  typename Internals::enable_if<Internals::is_same<T, JsonObject>::value,
-                                JsonObject>::type
-  to() {
-    clear();
-    JsonObject object(&_buffer);
-    _root = object;
-    return object;
-  }
-
-  // JsonArray to<JsonArray>()
-  template <typename T>
-  typename Internals::enable_if<Internals::is_same<T, JsonArray>::value,
-                                JsonArray>::type
-  to() {
-    clear();
-    JsonArray array(&_buffer);
-    _root = array;
-    return array;
-  }
-
-  // JsonVariant& to<JsonVariant>()
-  template <typename T>
-  typename Internals::enable_if<Internals::is_same<T, JsonVariant>::value,
-                                T&>::type
-  to() {
-    clear();
-    return _root;
-  }
-
-  Internals::DynamicJsonBuffer& buffer() {
-    return _buffer;
-  }
-
-  void clear() {
-    _buffer.clear();
-    _root = JsonVariant();
-  }
-
-  size_t memoryUsage() const {
-    return _buffer.size();
-  }
-
-  template <typename Visitor>
-  void visit(Visitor& visitor) const {
-    return _root.visit(visitor);
-  }
-};
-}  // namespace ArduinoJson

src/ArduinoJson/Json/EscapeSequence.hpp

@@ -4,8 +4,7 @@
 
 #pragma once
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 class EscapeSequence {
  public:
@@ -33,5 +32,4 @@ class EscapeSequence {
     return &"\"\"\\\\b\bf\fn\nr\rt\t"[excludeIdenticals ? 4 : 0];
   }
 };
-}  // namespace Internals
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Json/IndentedPrint.hpp

@@ -4,8 +4,7 @@
 
 #pragma once
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 // Decorator on top of Print to allow indented output.
 // This class is used by serializeJsonPretty() but can also be used
@@ -67,5 +66,4 @@ class IndentedPrint {
   static const int MAX_LEVEL = 15;    // because it's only 4 bits
   static const int MAX_TAB_SIZE = 7;  // because it's only 3 bits
 };
-}  // namespace Internals
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Json/JsonDeserializer.hpp

@@ -6,24 +6,29 @@
 
 #include "../Deserialization/deserialize.hpp"
 #include "../JsonVariant.hpp"
-#include "../Memory/JsonBuffer.hpp"
+#include "../Memory/MemoryPool.hpp"
+#include "../Numbers/isFloat.hpp"
+#include "../Numbers/isInteger.hpp"
 #include "../Polyfills/type_traits.hpp"
 #include "./EscapeSequence.hpp"
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 template <typename TReader, typename TStringStorage>
 class JsonDeserializer {
+  typedef typename remove_reference<TStringStorage>::type::StringBuilder
+      StringBuilder;
+  typedef typename StringBuilder::StringType StringType;
+
  public:
-  JsonDeserializer(JsonBuffer *buffer, TReader reader,
+  JsonDeserializer(MemoryPool &memoryPool, TReader reader,
                    TStringStorage stringStorage, uint8_t nestingLimit)
-      : _buffer(buffer),
+      : _memoryPool(&memoryPool),
         _reader(reader),
         _stringStorage(stringStorage),
         _nestingLimit(nestingLimit),
         _loaded(false) {}
-  DeserializationError parse(JsonVariant &variant) {
+  DeserializationError parse(JsonVariant variant) {
     DeserializationError err = skipSpacesAndComments();
     if (err) return err;
 
@@ -63,12 +68,11 @@ class JsonDeserializer {
     return true;
   }
 
-  DeserializationError parseArray(JsonVariant &variant) {
+  DeserializationError parseArray(JsonVariant variant) {
     if (_nestingLimit == 0) return DeserializationError::TooDeep;
 
-    JsonArray array(_buffer);
+    JsonArray array = variant.to<JsonArray>();
     if (array.isNull()) return DeserializationError::NoMemory;
-    variant = array;
 
     // Check opening braket
     if (!eat('[')) return DeserializationError::InvalidInput;
@@ -82,13 +86,15 @@ class JsonDeserializer {
 
     // Read each value
     for (;;) {
+      // Allocate slot in array
+      JsonVariant value = array.add();
+      if (value.isInvalid()) return DeserializationError::NoMemory;
+
       // 1 - Parse value
-      JsonVariant value;
       _nestingLimit--;
       err = parse(value);
       _nestingLimit++;
       if (err) return err;
-      if (!array.add(value)) return DeserializationError::NoMemory;
 
       // 2 - Skip spaces
       err = skipSpacesAndComments();
@@ -100,12 +106,11 @@ class JsonDeserializer {
     }
   }
 
-  DeserializationError parseObject(JsonVariant &variant) {
+  DeserializationError parseObject(JsonVariant variant) {
     if (_nestingLimit == 0) return DeserializationError::TooDeep;
 
-    JsonObject object(_buffer);
+    JsonObject object = variant.to<JsonObject>();
     if (object.isNull()) return DeserializationError::NoMemory;
-    variant = object;
 
     // Check opening brace
     if (!eat('{')) return DeserializationError::InvalidInput;
@@ -120,8 +125,8 @@ class JsonDeserializer {
     // Read each key value pair
     for (;;) {
       // Parse key
-      const char *key;
-      err = parseKey(&key);
+      StringType key;
+      err = parseKey(key);
       if (err) return err;
 
       // Skip spaces
@@ -129,13 +134,15 @@ class JsonDeserializer {
       if (err) return err;  // Colon
       if (!eat(':')) return DeserializationError::InvalidInput;
 
+      // Allocate slot in object
+      JsonVariant value = object.set(key);
+      if (value.isInvalid()) return DeserializationError::NoMemory;
+
       // Parse value
-      JsonVariant value;
       _nestingLimit--;
       err = parse(value);
       _nestingLimit++;
       if (err) return err;
-      if (!object.set(key, value)) return DeserializationError::NoMemory;
 
       // Skip spaces
       err = skipSpacesAndComments();
@@ -151,7 +158,7 @@ class JsonDeserializer {
     }
   }
 
-  DeserializationError parseValue(JsonVariant &variant) {
+  DeserializationError parseValue(JsonVariant variant) {
     if (isQuote(current())) {
       return parseStringValue(variant);
     } else {
@@ -159,7 +166,7 @@ class JsonDeserializer {
     }
   }
 
-  DeserializationError parseKey(const char **key) {
+  DeserializationError parseKey(StringType &key) {
     if (isQuote(current())) {
       return parseQuotedString(key);
     } else {
@@ -167,19 +174,17 @@ class JsonDeserializer {
     }
   }
 
-  DeserializationError parseStringValue(JsonVariant &variant) {
-    const char *value;
-    DeserializationError err = parseQuotedString(&value);
+  DeserializationError parseStringValue(JsonVariant variant) {
+    StringType value;
+    DeserializationError err = parseQuotedString(value);
     if (err) return err;
-    variant = value;
+    variant.set(value);
     return DeserializationError::Ok;
   }
 
-  DeserializationError parseQuotedString(const char **result) {
-    typename remove_reference<TStringStorage>::type::String str =
-        _stringStorage.startString();
-
-    char stopChar = current();
+  DeserializationError parseQuotedString(StringType &result) {
+    StringBuilder builder = _stringStorage.startString();
+    const char stopChar = current();
 
     move();
     for (;;) {
@@ -199,17 +204,16 @@ class JsonDeserializer {
         move();
       }
 
-      str.append(c);
+      builder.append(c);
     }
 
-    *result = str.c_str();
-    if (*result == NULL) return DeserializationError::NoMemory;
+    result = builder.complete();
+    if (result.isNull()) return DeserializationError::NoMemory;
     return DeserializationError::Ok;
   }
 
-  DeserializationError parseNonQuotedString(const char **result) {
-    typename remove_reference<TStringStorage>::type::String str =
-        _stringStorage.startString();
+  DeserializationError parseNonQuotedString(StringType &result) {
+    StringBuilder builder = _stringStorage.startString();
 
     char c = current();
     if (c == '\0') return DeserializationError::IncompleteInput;
@@ -217,19 +221,19 @@ class JsonDeserializer {
     if (canBeInNonQuotedString(c)) {  // no quotes
       do {
         move();
-        str.append(c);
+        builder.append(c);
         c = current();
       } while (canBeInNonQuotedString(c));
     } else {
       return DeserializationError::InvalidInput;
     }
 
-    *result = str.c_str();
-    if (*result == NULL) return DeserializationError::NoMemory;
+    result = builder.complete();
+    if (result.isNull()) return DeserializationError::NoMemory;
     return DeserializationError::Ok;
   }
 
-  DeserializationError parseNumericValue(JsonVariant &result) {
+  DeserializationError parseNumericValue(JsonVariant result) {
     char buffer[64];
     uint8_t n = 0;
 
@@ -242,15 +246,15 @@ class JsonDeserializer {
     buffer[n] = 0;
 
     if (isInteger(buffer)) {
-      result = parseInteger<JsonInteger>(buffer);
+      result.set(parseInteger<JsonInteger>(buffer));
     } else if (isFloat(buffer)) {
-      result = parseFloat<JsonFloat>(buffer);
+      result.set(parseFloat<JsonFloat>(buffer));
     } else if (!strcmp(buffer, "true")) {
-      result = true;
+      result.set(true);
     } else if (!strcmp(buffer, "false")) {
-      result = false;
+      result.set(false);
     } else if (!strcmp(buffer, "null")) {
-      result = static_cast<const char *>(0);
+      // already null
     } else {
       return DeserializationError::InvalidInput;
     }
@@ -329,37 +333,32 @@ class JsonDeserializer {
     }
   }
 
-  JsonBuffer *_buffer;
+  MemoryPool *_memoryPool;
   TReader _reader;
   TStringStorage _stringStorage;
   uint8_t _nestingLimit;
   char _current;
   bool _loaded;
-};  // namespace Internals
-}  // namespace Internals
+};
 
 template <typename TDocument, typename TInput>
 DeserializationError deserializeJson(TDocument &doc, const TInput &input) {
-  using namespace Internals;
   return deserialize<JsonDeserializer>(doc, input);
 }
 
 template <typename TDocument, typename TInput>
 DeserializationError deserializeJson(TDocument &doc, TInput *input) {
-  using namespace Internals;
   return deserialize<JsonDeserializer>(doc, input);
 }
 
 template <typename TDocument, typename TInput>
 DeserializationError deserializeJson(TDocument &doc, TInput *input,
                                      size_t inputSize) {
-  using namespace Internals;
   return deserialize<JsonDeserializer>(doc, input, inputSize);
 }
 
 template <typename TDocument, typename TInput>
 DeserializationError deserializeJson(TDocument &doc, TInput &input) {
-  using namespace Internals;
   return deserialize<JsonDeserializer>(doc, input);
 }
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Json/JsonSerializer.hpp

@@ -6,26 +6,26 @@
 
 #include "../Serialization/measure.hpp"
 #include "../Serialization/serialize.hpp"
-#include "./JsonWriter.hpp"
+#include "../Visitable.hpp"
+#include "JsonWriter.hpp"
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 template <typename TWriter>
 class JsonSerializer {
  public:
   JsonSerializer(TWriter &writer) : _writer(writer) {}
 
-  void acceptFloat(JsonFloat value) {
+  void visitFloat(JsonFloat value) {
     _writer.writeFloat(value);
   }
 
-  void acceptArray(const JsonArray &array) {
+  void visitArray(JsonArrayConst array) {
     _writer.beginArray();
 
-    JsonArray::const_iterator it = array.begin();
+    JsonArrayConst::iterator it = array.begin();
     while (it != array.end()) {
-      it->visit(*this);
+      it->accept(*this);
 
       ++it;
       if (it == array.end()) break;
@@ -36,14 +36,14 @@ class JsonSerializer {
     _writer.endArray();
   }
 
-  void acceptObject(const JsonObject &object) {
+  void visitObject(JsonObjectConst object) {
     _writer.beginObject();
 
-    JsonObject::const_iterator it = object.begin();
+    JsonObjectConst::iterator it = object.begin();
     while (it != object.end()) {
-      _writer.writeString(it->key);
+      _writer.writeString(it->key());
       _writer.writeColon();
-      it->value.visit(*this);
+      it->value().accept(*this);
 
       ++it;
       if (it == object.end()) break;
@@ -54,29 +54,29 @@ class JsonSerializer {
     _writer.endObject();
   }
 
-  void acceptString(const char *value) {
+  void visitString(const char *value) {
     _writer.writeString(value);
   }
 
-  void acceptRawJson(const char *data, size_t n) {
+  void visitRawJson(const char *data, size_t n) {
     // TODO
     for (size_t i = 0; i < n; i++) _writer.writeRaw(data[i]);
   }
 
-  void acceptNegativeInteger(JsonUInt value) {
+  void visitNegativeInteger(JsonUInt value) {
     _writer.writeRaw('-');
     _writer.writeInteger(value);
   }
 
-  void acceptPositiveInteger(JsonUInt value) {
+  void visitPositiveInteger(JsonUInt value) {
     _writer.writeInteger(value);
   }
 
-  void acceptBoolean(bool value) {
+  void visitBoolean(bool value) {
     _writer.writeBoolean(value);
   }
 
-  void acceptNull() {
+  void visitNull() {
     _writer.writeRaw("null");
   }
 
@@ -88,55 +88,28 @@ class JsonSerializer {
   JsonWriter<TWriter> _writer;
 };
 
-}  // namespace Internals
-
 template <typename TSource, typename TDestination>
-size_t serializeJson(TSource &source, TDestination &destination) {
-  using namespace Internals;
+size_t serializeJson(const TSource &source, TDestination &destination) {
   return serialize<JsonSerializer>(source, destination);
 }
 
 template <typename TSource>
 size_t serializeJson(const TSource &source, char *buffer, size_t bufferSize) {
-  using namespace Internals;
   return serialize<JsonSerializer>(source, buffer, bufferSize);
 }
 
 template <typename TSource>
 size_t measureJson(const TSource &source) {
-  using namespace Internals;
   return measure<JsonSerializer>(source);
 }
 
 #if ARDUINOJSON_ENABLE_STD_STREAM
-inline std::ostream &operator<<(std::ostream &os, const JsonArray &source) {
+template <typename T>
+inline typename enable_if<IsVisitable<T>::value, std::ostream &>::type
+operator<<(std::ostream &os, const T &source) {
   serializeJson(source, os);
   return os;
 }
-inline std::ostream &operator<<(std::ostream &os, const JsonObject &source) {
-  serializeJson(source, os);
-  return os;
-}
-inline std::ostream &operator<<(std::ostream &os, const JsonVariant &source) {
-  serializeJson(source, os);
-  return os;
-}
-
-namespace Internals {
-inline std::ostream &operator<<(std::ostream &os,
-                                const JsonArraySubscript &source) {
-  serializeJson(source, os);
-  return os;
-}
-
-template <typename TKey>
-inline std::ostream &operator<<(std::ostream &os,
-                                const JsonObjectSubscript<TKey> &source) {
-  serializeJson(source, os);
-  return os;
-}
-}  // namespace Internals
-
 #endif
 
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Json/JsonWriter.hpp

@@ -11,8 +11,7 @@
 #include "../Polyfills/attributes.hpp"
 #include "./EscapeSequence.hpp"
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 template <typename TWriter>
 class JsonWriter {
@@ -154,5 +153,4 @@ class JsonWriter {
  private:
   JsonWriter &operator=(const JsonWriter &);  // cannot be assigned
 };
-}  // namespace Internals
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Json/PrettyJsonSerializer.hpp

@@ -10,8 +10,7 @@
 #include "./JsonSerializer.hpp"
 #include "./Prettyfier.hpp"
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 template <typename TPrint>
 class PrettyJsonSerializer_Base {
@@ -33,25 +32,21 @@ class PrettyJsonSerializer : PrettyJsonSerializer_Base<TPrint>,
         JsonSerializer<Prettyfier<TPrint> >(
             PrettyJsonSerializer_Base<TPrint>::_prettyfier) {}
 };
-}  // namespace Internals
 
 template <typename TSource, typename TDestination>
 size_t serializeJsonPretty(TSource &source, TDestination &destination) {
-  using namespace Internals;
   return serialize<PrettyJsonSerializer>(source, destination);
 }
 
 template <typename TSource>
 size_t serializeJsonPretty(const TSource &source, char *buffer,
                            size_t bufferSize) {
-  using namespace Internals;
   return serialize<PrettyJsonSerializer>(source, buffer, bufferSize);
 }
 
 template <typename TSource>
 size_t measureJsonPretty(const TSource &source) {
-  using namespace Internals;
   return measure<PrettyJsonSerializer>(source);
 }
 
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Json/Prettyfier.hpp

@@ -6,8 +6,7 @@
 
 #include "IndentedPrint.hpp"
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 // Converts a compact JSON string into an indented one.
 template <typename TWriter>
@@ -141,5 +140,4 @@ class Prettyfier {
   IndentedPrint<TWriter>& _sink;
   bool _inString;
 };
-}  // namespace Internals
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/JsonArray.hpp

@@ -4,72 +4,134 @@
 
 #pragma once
 
-#include "./JsonArrayData.hpp"
+#include "Data/ArrayFunctions.hpp"
+#include "Data/JsonVariantData.hpp"
+#include "JsonArrayIterator.hpp"
 
-namespace ArduinoJson {
+// Returns the size (in bytes) of an array with n elements.
+// Can be very handy to determine the size of a StaticMemoryPool.
+#define JSON_ARRAY_SIZE(NUMBER_OF_ELEMENTS) \
+  ((NUMBER_OF_ELEMENTS) * sizeof(ARDUINOJSON_NAMESPACE::VariantSlot))
+
+namespace ARDUINOJSON_NAMESPACE {
 
 class JsonObject;
-
-namespace Internals {
 class JsonArraySubscript;
-}
 
-class JsonArray {
-  friend class JsonVariant;
+template <typename TData>
+class JsonArrayProxy {
+ public:
+  FORCE_INLINE bool isNull() const {
+    return _data == 0;
+  }
+
+  FORCE_INLINE JsonVariantConst operator[](size_t index) const {
+    return JsonVariantConst(arrayGet(_data, index));
+  }
+
+  FORCE_INLINE size_t size() const {
+    return arraySize(_data);
+  }
+
+ protected:
+  JsonArrayProxy(TData* data) : _data(data) {}
+  TData* _data;
+};
+
+class JsonArrayConst : public JsonArrayProxy<const JsonArrayData>,
+                       public Visitable {
+  friend class JsonArray;
+  typedef JsonArrayProxy<const JsonArrayData> proxy_type;
 
  public:
-  typedef Internals::JsonArrayData::iterator iterator;
-  typedef Internals::JsonArrayData::const_iterator const_iterator;
+  typedef JsonArrayConstIterator iterator;
 
-  JsonArray() : _data(0) {}
-  JsonArray(Internals::JsonArrayData* arr) : _data(arr) {}
-  JsonArray(Internals::JsonBuffer* buf)
-      : _data(new (buf) Internals::JsonArrayData(buf)) {}
+  template <typename Visitor>
+  FORCE_INLINE void accept(Visitor& visitor) const {
+    if (_data)
+      visitor.visitArray(*this);
+    else
+      visitor.visitNull();
+  }
+
+  FORCE_INLINE iterator begin() const {
+    if (!_data) return iterator();
+    return iterator(_data->head);
+  }
+
+  FORCE_INLINE iterator end() const {
+    return iterator();
+  }
+
+  FORCE_INLINE JsonArrayConst() : proxy_type(0) {}
+  FORCE_INLINE JsonArrayConst(const JsonArrayData* data) : proxy_type(data) {}
+
+  FORCE_INLINE bool operator==(JsonArrayConst rhs) const {
+    return arrayEquals(_data, rhs._data);
+  }
+};
+
+class JsonArray : public JsonArrayProxy<JsonArrayData>, public Visitable {
+  typedef JsonArrayProxy<JsonArrayData> proxy_type;
+
+ public:
+  typedef JsonArrayIterator iterator;
+
+  FORCE_INLINE JsonArray() : proxy_type(0), _memoryPool(0) {}
+  FORCE_INLINE JsonArray(MemoryPool* pool, JsonArrayData* data)
+      : proxy_type(data), _memoryPool(pool) {}
+
+  operator JsonVariant() {
+    return JsonVariant(_memoryPool, getVariantData(_data));
+  }
+
+  operator JsonArrayConst() const {
+    return JsonArrayConst(_data);
+  }
 
   // Adds the specified value at the end of the array.
   //
   // bool add(TValue);
   // TValue = bool, long, int, short, float, double, serialized, JsonVariant,
-  //          std::string, String, JsonArrayData, JsonObject
+  //          std::string, String, JsonObject
   template <typename T>
-  bool add(const T& value) {
-    return add_impl<const T&>(value);
+  FORCE_INLINE bool add(const T& value) const {
+    return add().set(value);
+  }
+  // Adds the specified value at the end of the array.
+  FORCE_INLINE bool add(JsonArray value) const {
+    return add().set(value);
   }
   //
   // bool add(TValue);
   // TValue = char*, const char*, const FlashStringHelper*
   template <typename T>
-  bool add(T* value) {
-    return add_impl<T*>(value);
+  FORCE_INLINE bool add(T* value) const {
+    return add().set(value);
   }
 
-  iterator begin() {
+  JsonVariant add() const {
+    return JsonVariant(_memoryPool, arrayAdd(_data, _memoryPool));
+  }
+
+  FORCE_INLINE iterator begin() const {
     if (!_data) return iterator();
-    return _data->begin();
+    return iterator(_memoryPool, _data->head);
   }
 
-  const_iterator begin() const {
-    if (!_data) return const_iterator();
-    return _data->begin();
-  }
-
-  iterator end() {
+  FORCE_INLINE iterator end() const {
     return iterator();
   }
 
-  const_iterator end() const {
-    return const_iterator();
-  }
-
   // Imports a 1D array
   template <typename T, size_t N>
-  bool copyFrom(T (&array)[N]) {
+  FORCE_INLINE bool copyFrom(T (&array)[N]) const {
     return copyFrom(array, N);
   }
 
   // Imports a 1D array
   template <typename T>
-  bool copyFrom(T* array, size_t len) {
+  bool copyFrom(T* array, size_t len) const {
     bool ok = true;
     for (size_t i = 0; i < len; i++) {
       ok &= add(array[i]);
@@ -79,7 +141,7 @@ class JsonArray {
 
   // Imports a 2D array
   template <typename T, size_t N1, size_t N2>
-  bool copyFrom(T (&array)[N1][N2]) {
+  bool copyFrom(T (&array)[N1][N2]) const {
     bool ok = true;
     for (size_t i = 0; i < N1; i++) {
       JsonArray nestedArray = createNestedArray();
@@ -90,9 +152,14 @@ class JsonArray {
     return ok;
   }
 
+  // Copy a JsonArray
+  FORCE_INLINE bool copyFrom(JsonArray src) const {
+    return arrayCopy(_data, src._data, _memoryPool);
+  }
+
   // Exports a 1D array
   template <typename T, size_t N>
-  size_t copyTo(T (&array)[N]) const {
+  FORCE_INLINE size_t copyTo(T (&array)[N]) const {
     return copyTo(array, N);
   }
 
@@ -100,8 +167,7 @@ class JsonArray {
   template <typename T>
   size_t copyTo(T* array, size_t len) const {
     size_t i = 0;
-    for (const_iterator it = begin(); it != end() && i < len; ++it)
-      array[i++] = *it;
+    for (iterator it = begin(); it != end() && i < len; ++it) array[i++] = *it;
     return i;
   }
 
@@ -110,99 +176,46 @@ class JsonArray {
   void copyTo(T (&array)[N1][N2]) const {
     if (!_data) return;
     size_t i = 0;
-    for (const_iterator it = begin(); it != end() && i < N1; ++it) {
+    for (iterator it = begin(); it != end() && i < N1; ++it) {
       it->as<JsonArray>().copyTo(array[i++]);
     }
   }
 
-  JsonArray createNestedArray();
-  JsonObject createNestedObject();
+  FORCE_INLINE JsonArray createNestedArray() const;
+  FORCE_INLINE JsonObject createNestedObject() const;
 
-  Internals::JsonArraySubscript operator[](size_t index);
+  FORCE_INLINE JsonArraySubscript operator[](size_t index) const;
 
-  const Internals::JsonArraySubscript operator[](size_t index) const;
-
-  bool operator==(const JsonArray& rhs) const {
-    return _data == rhs._data;
+  FORCE_INLINE bool operator==(JsonArray rhs) const {
+    return arrayEquals(_data, rhs._data);
   }
 
   // Gets the value at the specified index.
-  template <typename T>
-  typename Internals::JsonVariantAs<T>::type get(size_t index) const {
-    const_iterator it = begin() += index;
-    return it != end() ? it->as<T>() : Internals::JsonVariantDefault<T>::get();
-  }
-
-  // Check the type of the value at specified index.
-  template <typename T>
-  bool is(size_t index) const {
-    const_iterator it = begin() += index;
-    return it != end() ? it->is<T>() : false;
+  FORCE_INLINE JsonVariant get(size_t index) const {
+    return JsonVariant(_memoryPool, arrayGet(_data, index));
   }
 
   // Removes element at specified position.
-  void remove(iterator it) {
-    if (!_data) return;
-    _data->remove(it);
+  FORCE_INLINE void remove(iterator it) const {
+    arrayRemove(_data, it.internal(), _memoryPool);
   }
 
   // Removes element at specified index.
-  void remove(size_t index) {
-    remove(begin() += index);
-  }
-
-  // Sets the value at specified index.
-  //
-  // bool add(size_t index, const TValue&);
-  // TValue = bool, long, int, short, float, double, serialized, JsonVariant,
-  //          std::string, String, JsonArrayData, JsonObject
-  template <typename T>
-  bool set(size_t index, const T& value) {
-    if (!_data) return false;
-    return set_impl<const T&>(index, value);
-  }
-  //
-  // bool add(size_t index, TValue);
-  // TValue = char*, const char*, const FlashStringHelper*
-  template <typename T>
-  bool set(size_t index, T* value) {
-    if (!_data) return false;
-    return set_impl<T*>(index, value);
-  }
-
-  size_t size() const {
-    if (!_data) return 0;
-    return _data->size();
-  }
-
-  bool isNull() const {
-    return _data == 0;
+  FORCE_INLINE void remove(size_t index) const {
+    arrayRemove(_data, index, _memoryPool);
   }
 
   template <typename Visitor>
-  void visit(Visitor& visitor) const {
-    if (_data)
-      return visitor.acceptArray(*this);
-    else
-      visitor.acceptNull();
+  FORCE_INLINE void accept(Visitor& visitor) const {
+    JsonArrayConst(_data).accept(visitor);
   }
 
  private:
   template <typename TValueRef>
-  bool set_impl(size_t index, TValueRef value) {
-    iterator it = begin() += index;
-    if (it == end()) return false;
-    return Internals::ValueSaver<TValueRef>::save(_data->_buffer, *it, value);
+  FORCE_INLINE bool add_impl(TValueRef value) const {
+    return add().set(value);
   }
 
-  template <typename TValueRef>
-  bool add_impl(TValueRef value) {
-    if (!_data) return false;
-    iterator it = _data->add();
-    if (it == end()) return false;
-    return Internals::ValueSaver<TValueRef>::save(_data->_buffer, *it, value);
-  }
-
-  Internals::JsonArrayData* _data;
+  MemoryPool* _memoryPool;
 };
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/JsonArrayData.hpp

@@ -1,26 +0,0 @@
-// ArduinoJson - arduinojson.org
-// Copyright Benoit Blanchon 2014-2018
-// MIT License
-
-#pragma once
-
-#include "Data/List.hpp"
-#include "Data/ValueSaver.hpp"
-#include "JsonVariant.hpp"
-#include "Memory/JsonBufferAllocated.hpp"
-#include "Polyfills/type_traits.hpp"
-
-// Returns the size (in bytes) of an array with n elements.
-// Can be very handy to determine the size of a StaticJsonBuffer.
-#define JSON_ARRAY_SIZE(NUMBER_OF_ELEMENTS)        \
-  (sizeof(ArduinoJson::Internals::JsonArrayData) + \
-   (NUMBER_OF_ELEMENTS) *                          \
-       sizeof(ArduinoJson::Internals::JsonArrayData::node_type))
-
-namespace ArduinoJson {
-namespace Internals {
-struct JsonArrayData : List<JsonVariant>, JsonBufferAllocated {
-  explicit JsonArrayData(JsonBuffer *buf) throw() : List<JsonVariant>(buf) {}
-};
-}  // namespace Internals
-}  // namespace ArduinoJson

src/ArduinoJson/JsonArrayImpl.hpp

@@ -7,19 +7,13 @@
 #include "JsonArray.hpp"
 #include "JsonObject.hpp"
 
-namespace ArduinoJson {
+namespace ARDUINOJSON_NAMESPACE {
 
-inline JsonArray JsonArray::createNestedArray() {
-  if (!_data) return JsonArray();
-  JsonArray array(_data->_buffer);
-  if (!array.isNull()) add(array);
-  return array;
+inline JsonArray JsonArray::createNestedArray() const {
+  return add().to<JsonArray>();
 }
 
-inline JsonObject JsonArray::createNestedObject() {
-  if (!_data) return JsonObject();
-  JsonObject object(_data->_buffer);
-  if (!object.isNull()) add(object);
-  return object;
+inline JsonObject JsonArray::createNestedObject() const {
+  return add().to<JsonObject>();
 }
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/JsonArrayIterator.hpp

@@ -0,0 +1,122 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2018
+// MIT License
+
+#pragma once
+
+#include "Data/SlotFunctions.hpp"
+#include "JsonVariant.hpp"
+
+namespace ARDUINOJSON_NAMESPACE {
+
+class JsonVariantPtr {
+ public:
+  JsonVariantPtr(MemoryPool *memoryPool, JsonVariantData *data)
+      : _variant(memoryPool, data) {}
+
+  JsonVariant *operator->() {
+    return &_variant;
+  }
+
+  JsonVariant &operator*() {
+    return _variant;
+  }
+
+ private:
+  JsonVariant _variant;
+};
+
+class JsonArrayIterator {
+ public:
+  JsonArrayIterator() : _slot(0) {}
+  explicit JsonArrayIterator(MemoryPool *memoryPool, VariantSlot *slot)
+      : _memoryPool(memoryPool), _slot(slot) {}
+
+  JsonVariant operator*() const {
+    return JsonVariant(_memoryPool, &_slot->value);
+  }
+  JsonVariantPtr operator->() {
+    return JsonVariantPtr(_memoryPool, &_slot->value);
+  }
+
+  bool operator==(const JsonArrayIterator &other) const {
+    return _slot == other._slot;
+  }
+
+  bool operator!=(const JsonArrayIterator &other) const {
+    return _slot != other._slot;
+  }
+
+  JsonArrayIterator &operator++() {
+    _slot = _slot->next;
+    return *this;
+  }
+
+  JsonArrayIterator &operator+=(size_t distance) {
+    _slot = slotAdvance(_slot, distance);
+    return *this;
+  }
+
+  VariantSlot *internal() {
+    return _slot;
+  }
+
+ private:
+  MemoryPool *_memoryPool;
+  VariantSlot *_slot;
+};
+
+class JsonVariantConstPtr {
+ public:
+  JsonVariantConstPtr(const JsonVariantData *data) : _variant(data) {}
+
+  JsonVariantConst *operator->() {
+    return &_variant;
+  }
+
+  JsonVariantConst &operator*() {
+    return _variant;
+  }
+
+ private:
+  JsonVariantConst _variant;
+};
+
+class JsonArrayConstIterator {
+ public:
+  JsonArrayConstIterator() : _slot(0) {}
+  explicit JsonArrayConstIterator(const VariantSlot *slot) : _slot(slot) {}
+
+  JsonVariantConst operator*() const {
+    return JsonVariantConst(&_slot->value);
+  }
+  JsonVariantConstPtr operator->() {
+    return JsonVariantConstPtr(&_slot->value);
+  }
+
+  bool operator==(const JsonArrayConstIterator &other) const {
+    return _slot == other._slot;
+  }
+
+  bool operator!=(const JsonArrayConstIterator &other) const {
+    return _slot != other._slot;
+  }
+
+  JsonArrayConstIterator &operator++() {
+    _slot = _slot->next;
+    return *this;
+  }
+
+  JsonArrayConstIterator &operator+=(size_t distance) {
+    _slot = slotAdvance(_slot, distance);
+    return *this;
+  }
+
+  const VariantSlot *internal() {
+    return _slot;
+  }
+
+ private:
+  const VariantSlot *_slot;
+};
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/JsonArraySubscript.hpp

@@ -12,15 +12,15 @@
 #pragma warning(disable : 4522)
 #endif
 
-namespace ArduinoJson {
-namespace Internals {
-class JsonArraySubscript : public JsonVariantBase<JsonArraySubscript> {
+namespace ARDUINOJSON_NAMESPACE {
+class JsonArraySubscript : public JsonVariantBase<JsonArraySubscript>,
+                           public Visitable {
  public:
   FORCE_INLINE JsonArraySubscript(JsonArray array, size_t index)
       : _array(array), _index(index) {}
 
   FORCE_INLINE JsonArraySubscript& operator=(const JsonArraySubscript& src) {
-    _array.set(_index, src);
+    get_impl().set(src.as<JsonVariantConst>());
     return *this;
   }
 
@@ -31,7 +31,7 @@ class JsonArraySubscript : public JsonVariantBase<JsonArraySubscript> {
   //          std::string, String, JsonArray, JsonObject
   template <typename T>
   FORCE_INLINE JsonArraySubscript& operator=(const T& src) {
-    _array.set(_index, src);
+    get_impl().set(src);
     return *this;
   }
   //
@@ -39,22 +39,27 @@ class JsonArraySubscript : public JsonVariantBase<JsonArraySubscript> {
   // TValue = char*, const char*, const FlashStringHelper*
   template <typename T>
   FORCE_INLINE JsonArraySubscript& operator=(T* src) {
-    _array.set(_index, src);
+    get_impl().set(src);
     return *this;
   }
 
   FORCE_INLINE bool isNull() const {
-    return _index >= _array.size();
+    return get_impl().isNull();
   }
 
   template <typename T>
   FORCE_INLINE typename JsonVariantAs<T>::type as() const {
-    return _array.get<T>(_index);
+    return get_impl().as<T>();
   }
 
   template <typename T>
   FORCE_INLINE bool is() const {
-    return _array.is<T>(_index);
+    return get_impl().is<T>();
+  }
+
+  template <typename T>
+  FORCE_INLINE typename JsonVariantTo<T>::type to() const {
+    return get_impl().to<T>();
   }
 
   // Replaces the value
@@ -63,49 +68,45 @@ class JsonArraySubscript : public JsonVariantBase<JsonArraySubscript> {
   // TValue = bool, long, int, short, float, double, serialized, JsonVariant,
   //          std::string, String, JsonArray, JsonObject
   template <typename TValue>
-  FORCE_INLINE bool set(const TValue& value) {
-    return _array.set(_index, value);
+  FORCE_INLINE bool set(const TValue& value) const {
+    return get_impl().set(value);
   }
   //
   // bool set(TValue)
   // TValue = char*, const char*, const FlashStringHelper*
   template <typename TValue>
-  FORCE_INLINE bool set(TValue* value) {
-    return _array.set(_index, value);
+  FORCE_INLINE bool set(TValue* value) const {
+    return get_impl().set(value);
   }
 
   template <typename Visitor>
-  void visit(Visitor& visitor) const {
-    return _array.get<JsonVariant>(_index).visit(visitor);
+  void accept(Visitor& visitor) const {
+    return get_impl().accept(visitor);
+  }
+
+  FORCE_INLINE size_t size() const {
+    return get_impl().size();
   }
 
  private:
+  FORCE_INLINE JsonVariant get_impl() const {
+    return _array.get(_index);
+  }
+
   JsonArray _array;
   const size_t _index;
 };
 
 template <typename TImpl>
 inline JsonArraySubscript JsonVariantSubscripts<TImpl>::operator[](
-    size_t index) {
-  return impl()->template as<JsonArray>()[index];
-}
-
-template <typename TImpl>
-inline const JsonArraySubscript JsonVariantSubscripts<TImpl>::operator[](
     size_t index) const {
   return impl()->template as<JsonArray>()[index];
 }
-}  // namespace Internals
 
-inline Internals::JsonArraySubscript JsonArray::operator[](size_t index) {
-  return Internals::JsonArraySubscript(*this, index);
+inline JsonArraySubscript JsonArray::operator[](size_t index) const {
+  return JsonArraySubscript(*this, index);
 }
-
-inline const Internals::JsonArraySubscript JsonArray::operator[](
-    size_t index) const {
-  return Internals::JsonArraySubscript(*this, index);
-}
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE
 
 #ifdef _MSC_VER
 #pragma warning(pop)

src/ArduinoJson/JsonDocument.hpp

@@ -0,0 +1,131 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2018
+// MIT License
+
+#pragma once
+
+#include "Data/JsonVariantTo.hpp"
+#include "JsonVariant.hpp"
+#include "Memory/DynamicMemoryPool.hpp"
+#include "Memory/StaticMemoryPool.hpp"
+
+namespace ARDUINOJSON_NAMESPACE {
+
+template <typename TMemoryPool>
+class JsonDocument : public Visitable {
+ public:
+  uint8_t nestingLimit;
+
+  JsonDocument() : nestingLimit(ARDUINOJSON_DEFAULT_NESTING_LIMIT) {}
+
+  template <typename Visitor>
+  void accept(Visitor& visitor) const {
+    return getVariant().accept(visitor);
+  }
+
+  template <typename T>
+  typename JsonVariantAs<T>::type as() {
+    return getVariant().template as<T>();
+  }
+
+  template <typename T>
+  typename JsonVariantConstAs<T>::type as() const {
+    return getVariant().template as<T>();
+  }
+
+  void clear() {
+    _memoryPool.clear();
+    _rootData.type = JSON_NULL;
+  }
+
+  template <typename T>
+  bool is() const {
+    return getVariant().template is<T>();
+  }
+
+  size_t memoryUsage() const {
+    return _memoryPool.size();
+  }
+
+  TMemoryPool& memoryPool() {
+    return _memoryPool;
+  }
+
+  template <typename T>
+  typename JsonVariantTo<T>::type to() {
+    clear();
+    return getVariant().template to<T>();
+  }
+
+ protected:
+  template <typename T>
+  void copy(const JsonDocument<T>& src) {
+    nestingLimit = src.nestingLimit;
+    to<JsonVariant>().set(src.template as<JsonVariant>());
+  }
+
+ private:
+  JsonVariant getVariant() {
+    return JsonVariant(&_memoryPool, &_rootData);
+  }
+
+  JsonVariantConst getVariant() const {
+    return JsonVariantConst(&_rootData);
+  }
+
+  TMemoryPool _memoryPool;
+  JsonVariantData _rootData;
+};
+
+class DynamicJsonDocument : public JsonDocument<DynamicMemoryPool> {
+ public:
+  DynamicJsonDocument() {}
+  DynamicJsonDocument(size_t capacity) {
+    memoryPool().reserve(capacity);
+  }
+
+  DynamicJsonDocument(const DynamicJsonDocument& src) {
+    memoryPool().reserve(src.memoryUsage());
+    copy(src);
+  }
+
+  template <typename T>
+  DynamicJsonDocument(const JsonDocument<T>& src) {
+    memoryPool().reserve(src.memoryUsage());
+    copy(src);
+  }
+
+  DynamicJsonDocument& operator=(const DynamicJsonDocument& src) {
+    copy(src);
+    return *this;
+  }
+
+  template <typename T>
+  DynamicJsonDocument& operator=(const JsonDocument<T>& src) {
+    copy(src);
+    return *this;
+  }
+};
+
+template <size_t CAPACITY>
+class StaticJsonDocument : public JsonDocument<StaticMemoryPool<CAPACITY> > {
+ public:
+  StaticJsonDocument() {}
+
+  template <typename T>
+  StaticJsonDocument(const JsonDocument<T>& src) {
+    this->copy(src);
+  }
+
+  StaticMemoryPoolBase& memoryPool() {
+    return JsonDocument<StaticMemoryPool<CAPACITY> >::memoryPool();
+  }
+
+  template <typename T>
+  StaticJsonDocument operator=(const JsonDocument<T>& src) {
+    this->copy(src);
+    return *this;
+  }
+};
+
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/JsonKey.hpp

@@ -0,0 +1,33 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2018
+// MIT License
+
+#pragma once
+
+namespace ARDUINOJSON_NAMESPACE {
+
+class JsonKey {
+ public:
+  JsonKey(const VariantSlot* slot) : _slot(slot) {}
+
+  operator const char*() const {
+    return c_str();
+  }
+
+  const char* c_str() const {
+    return _slot ? slotGetKey(_slot) : 0;
+  }
+
+  bool isNull() const {
+    return _slot == 0 || _slot->linkedKey == 0;
+  }
+
+  friend bool operator==(JsonKey lhs, const char* rhs) {
+    if (lhs.isNull()) return rhs == 0;
+    return rhs ? !strcmp(lhs, rhs) : false;
+  }
+
+ private:
+  const VariantSlot* _slot;
+};
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/JsonObject.hpp

@@ -4,82 +4,185 @@
 
 #pragma once
 
-#include "./JsonObjectData.hpp"
+#include "Data/ObjectFunctions.hpp"
+#include "JsonObjectIterator.hpp"
 
-namespace ArduinoJson {
+// Returns the size (in bytes) of an object with n elements.
+// Can be very handy to determine the size of a StaticMemoryPool.
+#define JSON_OBJECT_SIZE(NUMBER_OF_ELEMENTS) \
+  ((NUMBER_OF_ELEMENTS) * sizeof(ARDUINOJSON_NAMESPACE::VariantSlot))
 
-class JsonObject {
-  friend class JsonVariant;
+namespace ARDUINOJSON_NAMESPACE {
 
+template <typename TData>
+class JsonObjectProxy {
  public:
-  typedef Internals::JsonObjectData::iterator iterator;
-  typedef Internals::JsonObjectData::const_iterator const_iterator;
-
-  JsonObject() : _data(0) {}
-  JsonObject(Internals::JsonObjectData* object) : _data(object) {}
-  JsonObject(Internals::JsonBuffer* buf)
-      : _data(new (buf) Internals::JsonObjectData(buf)) {}
-
-  iterator begin() {
-    if (!_data) return iterator();
-    return _data->begin();
-  }
-
-  const_iterator begin() const {
-    if (!_data) return const_iterator();
-    return _data->begin();
-  }
-
   // Tells weither the specified key is present and associated with a value.
   //
   // bool containsKey(TKey);
   // TKey = const std::string&, const String&
-  template <typename TString>
-  bool containsKey(const TString& key) const {
-    return containsKey_impl<const TString&>(key);
+  template <typename TKey>
+  FORCE_INLINE bool containsKey(const TKey& key) const {
+    return objectContainsKey(_data, makeString(key));
   }
   //
   // bool containsKey(TKey);
   // TKey = char*, const char*, char[], const char[], const FlashStringHelper*
-  template <typename TString>
-  bool containsKey(TString* key) const {
-    return containsKey_impl<TString*>(key);
+  template <typename TKey>
+  FORCE_INLINE bool containsKey(TKey* key) const {
+    return objectContainsKey(_data, makeString(key));
   }
 
-  iterator end() {
+  FORCE_INLINE bool isNull() const {
+    return _data == 0;
+  }
+
+  FORCE_INLINE size_t size() const {
+    return objectSize(_data);
+  }
+
+ protected:
+  JsonObjectProxy(TData* data) : _data(data) {}
+  TData* _data;
+};
+
+class JsonObjectConst : public JsonObjectProxy<const JsonObjectData>,
+                        public Visitable {
+  friend class JsonObject;
+  typedef JsonObjectProxy<const JsonObjectData> proxy_type;
+
+ public:
+  typedef JsonObjectConstIterator iterator;
+
+  JsonObjectConst() : proxy_type(0) {}
+  JsonObjectConst(const JsonObjectData* data) : proxy_type(data) {}
+
+  template <typename Visitor>
+  FORCE_INLINE void accept(Visitor& visitor) const {
+    if (_data)
+      visitor.visitObject(*this);
+    else
+      visitor.visitNull();
+  }
+
+  FORCE_INLINE iterator begin() const {
+    if (!_data) return iterator();
+    return iterator(_data->head);
+  }
+
+  FORCE_INLINE iterator end() const {
     return iterator();
   }
 
-  const_iterator end() const {
-    return const_iterator();
+  // Gets the value associated with the specified key.
+  //
+  // TValue get<TValue>(TKey) const;
+  // TKey = const std::string&, const String&
+  // TValue = bool, char, long, int, short, float, double,
+  //          std::string, String, JsonArrayConst, JsonObjectConst
+  template <typename TKey>
+  FORCE_INLINE JsonVariantConst get(const TKey& key) const {
+    return get_impl(makeString(key));
+  }
+  //
+  // TValue get<TValue>(TKey) const;
+  // TKey = char*, const char*, const FlashStringHelper*
+  // TValue = bool, char, long, int, short, float, double,
+  //          std::string, String, JsonArrayConst, JsonObjectConst
+  template <typename TKey>
+  FORCE_INLINE JsonVariantConst get(TKey* key) const {
+    return get_impl(makeString(key));
+  }
+
+  //
+  // JsonVariantConst operator[](TKey) const;
+  // TKey = const std::string&, const String&
+  template <typename TKey>
+  FORCE_INLINE typename enable_if<IsString<TKey>::value, JsonVariantConst>::type
+  operator[](const TKey& key) const {
+    return get_impl(makeString(key));
+  }
+  //
+  // JsonVariantConst operator[](TKey) const;
+  // TKey = const char*, const char[N], const FlashStringHelper*
+  template <typename TKey>
+  FORCE_INLINE
+      typename enable_if<IsString<TKey*>::value, JsonVariantConst>::type
+      operator[](TKey* key) const {
+    return get_impl(makeString(key));
+  }
+
+  FORCE_INLINE bool operator==(JsonObjectConst rhs) const {
+    return objectEquals(_data, rhs._data);
+  }
+
+ private:
+  template <typename TKey>
+  FORCE_INLINE JsonVariantConst get_impl(TKey key) const {
+    return JsonVariantConst(objectGet(_data, key));
+  }
+};
+
+class JsonObject : public JsonObjectProxy<JsonObjectData>, public Visitable {
+  typedef JsonObjectProxy<JsonObjectData> proxy_type;
+
+ public:
+  typedef JsonObjectIterator iterator;
+
+  FORCE_INLINE JsonObject() : proxy_type(0), _memoryPool(0) {}
+  FORCE_INLINE JsonObject(MemoryPool* buf, JsonObjectData* data)
+      : proxy_type(data), _memoryPool(buf) {}
+
+  operator JsonVariant() const {
+    return JsonVariant(_memoryPool, getVariantData(_data));
+  }
+
+  operator JsonObjectConst() const {
+    return JsonObjectConst(_data);
+  }
+
+  FORCE_INLINE iterator begin() const {
+    if (!_data) return iterator();
+    return iterator(_memoryPool, _data->head);
+  }
+
+  FORCE_INLINE iterator end() const {
+    return iterator();
+  }
+
+  void clear() const {
+    objectClear(_data);
+  }
+
+  FORCE_INLINE bool copyFrom(JsonObjectConst src) {
+    return objectCopy(_data, src._data, _memoryPool);
   }
 
   // Creates and adds a JsonArray.
   //
   // JsonArray createNestedArray(TKey);
   // TKey = const std::string&, const String&
-  template <typename TString>
-  JsonArray createNestedArray(const TString& key);
+  template <typename TKey>
+  FORCE_INLINE JsonArray createNestedArray(const TKey& key) const;
   // JsonArray createNestedArray(TKey);
   // TKey = char*, const char*, char[], const char[], const FlashStringHelper*
-  template <typename TString>
-  JsonArray createNestedArray(TString* key);
+  template <typename TKey>
+  FORCE_INLINE JsonArray createNestedArray(TKey* key) const;
 
   // Creates and adds a JsonObject.
   //
   // JsonObject createNestedObject(TKey);
   // TKey = const std::string&, const String&
-  template <typename TString>
-  JsonObject createNestedObject(const TString& key) {
-    if (!_data) return JsonObject();
-    return createNestedObject_impl<const TString&>(key);
+  template <typename TKey>
+  FORCE_INLINE JsonObject createNestedObject(const TKey& key) const {
+    return set(key).template to<JsonObject>();
   }
   //
   // JsonObject createNestedObject(TKey);
   // TKey = char*, const char*, char[], const char[], const FlashStringHelper*
-  template <typename TString>
-  JsonObject createNestedObject(TString* key) {
-    return createNestedObject_impl<TString*>(key);
+  template <typename TKey>
+  FORCE_INLINE JsonObject createNestedObject(TKey* key) const {
+    return set(key).template to<JsonObject>();
   }
 
   // Gets the value associated with the specified key.
@@ -88,224 +191,100 @@ class JsonObject {
   // TKey = const std::string&, const String&
   // TValue = bool, char, long, int, short, float, double,
   //          std::string, String, JsonArray, JsonObject
-  template <typename TValue, typename TString>
-  typename Internals::JsonVariantAs<TValue>::type get(
-      const TString& key) const {
-    return get_impl<const TString&, TValue>(key);
+  template <typename TKey>
+  FORCE_INLINE JsonVariant get(const TKey& key) const {
+    return get_impl(makeString(key));
   }
   //
   // TValue get<TValue>(TKey) const;
   // TKey = char*, const char*, const FlashStringHelper*
   // TValue = bool, char, long, int, short, float, double,
   //          std::string, String, JsonArray, JsonObject
-  template <typename TValue, typename TString>
-  typename Internals::JsonVariantAs<TValue>::type get(TString* key) const {
-    return get_impl<TString*, TValue>(key);
-  }
-
-  // Checks the type of the value associated with the specified key.
-  //
-  //
-  // bool is<TValue>(TKey) const;
-  // TKey = const std::string&, const String&
-  // TValue = bool, char, long, int, short, float, double,
-  //          std::string, String, JsonArray, JsonObject
-  template <typename TValue, typename TString>
-  bool is(const TString& key) const {
-    return is_impl<const TString&, TValue>(key);
-  }
-  //
-  // bool is<TValue>(TKey) const;
-  // TKey = char*, const char*, const FlashStringHelper*
-  // TValue = bool, char, long, int, short, float, double,
-  //          std::string, String, JsonArray, JsonObject
-  template <typename TValue, typename TString>
-  bool is(TString* key) const {
-    return is_impl<TString*, TValue>(key);
+  template <typename TKey>
+  FORCE_INLINE JsonVariant get(TKey* key) const {
+    return get_impl(makeString(key));
   }
 
   // Gets or sets the value associated with the specified key.
   //
   // JsonObjectSubscript operator[](TKey)
   // TKey = const std::string&, const String&
-  template <typename TString>
-  Internals::JsonObjectSubscript<const TString&> operator[](
-      const TString& key) {
-    return Internals::JsonObjectSubscript<const TString&>(*this, key);
+  template <typename TKey>
+  FORCE_INLINE JsonObjectSubscript<const TKey&> operator[](
+      const TKey& key) const {
+    return JsonObjectSubscript<const TKey&>(*this, key);
   }
   //
   // JsonObjectSubscript operator[](TKey)
   // TKey = char*, const char*, char[], const char[N], const FlashStringHelper*
-  template <typename TString>
-  Internals::JsonObjectSubscript<TString*> operator[](TString* key) {
-    return Internals::JsonObjectSubscript<TString*>(*this, key);
+  template <typename TKey>
+  FORCE_INLINE JsonObjectSubscript<TKey*> operator[](TKey* key) const {
+    return JsonObjectSubscript<TKey*>(*this, key);
   }
 
-  // Gets the value associated with the specified key.
-  //
-  // const JsonObjectSubscript operator[](TKey) const;
-  // TKey = const std::string&, const String&
-  template <typename TString>
-  const Internals::JsonObjectSubscript<const TString&> operator[](
-      const TString& key) const {
-    return Internals::JsonObjectSubscript<const TString&>(*this, key);
-  }
-  //
-  // const JsonObjectSubscript operator[](TKey) const;
-  // TKey = const char*, const char[N], const FlashStringHelper*
-  template <typename TString>
-  const Internals::JsonObjectSubscript<TString*> operator[](
-      TString* key) const {
-    return Internals::JsonObjectSubscript<TString*>(*this, key);
+  FORCE_INLINE bool operator==(JsonObject rhs) const {
+    return objectEquals(_data, rhs._data);
   }
 
-  bool operator==(const JsonObject& rhs) const {
-    return _data == rhs._data;
-  }
-
-  void remove(iterator it) {
-    if (!_data) return;
-    _data->remove(it);
+  FORCE_INLINE void remove(iterator it) const {
+    objectRemove(_data, it.internal(), _memoryPool);
   }
 
   // Removes the specified key and the associated value.
   //
   // void remove(TKey);
   // TKey = const std::string&, const String&
-  template <typename TString>
-  void remove(const TString& key) {
-    remove_impl<const TString&>(key);
+  template <typename TKey>
+  FORCE_INLINE void remove(const TKey& key) const {
+    remove_impl(makeString(key));
   }
   //
   // void remove(TKey);
   // TKey = char*, const char*, char[], const char[], const FlashStringHelper*
-  template <typename TString>
-  void remove(TString* key) {
-    remove_impl<TString*>(key);
+  template <typename TKey>
+  FORCE_INLINE void remove(TKey* key) const {
+    remove_impl(makeString(key));
   }
 
-  // Sets the specified key with the specified value.
-  //
-  // bool set(TKey, TValue);
-  // TKey = const std::string&, const String&
-  // TValue = bool, long, int, short, float, double, serialized, JsonVariant,
-  //          std::string, String, JsonArray, JsonObject
-  template <typename TValue, typename TString>
-  bool set(const TString& key, const TValue& value) {
-    return set_impl<const TString&, const TValue&>(key, value);
-  }
-  //
-  // bool set(TKey, TValue);
-  // TKey = const std::string&, const String&
-  // TValue = char*, const char*, const FlashStringHelper*
-  template <typename TValue, typename TString>
-  bool set(const TString& key, TValue* value) {
-    return set_impl<const TString&, TValue*>(key, value);
-  }
-  //
-  // bool set(TKey, const TValue&);
-  // TKey = char*, const char*, const FlashStringHelper*
-  // TValue = bool, long, int, short, float, double, serialized, JsonVariant,
-  //          std::string, String, JsonArray, JsonObject
-  template <typename TValue, typename TString>
-  bool set(TString* key, const TValue& value) {
-    return set_impl<TString*, const TValue&>(key, value);
-  }
-  //
-  // bool set(TKey, TValue);
-  // TKey = char*, const char*, const FlashStringHelper*
-  // TValue = char*, const char*, const FlashStringHelper*
-  template <typename TValue, typename TString>
-  bool set(TString* key, TValue* value) {
-    return set_impl<TString*, TValue*>(key, value);
+  template <typename TKey>
+  FORCE_INLINE JsonVariant set(TKey* key) const {
+    return set_impl(makeString(key));
   }
 
-  size_t size() const {
-    if (!_data) return 0;
-    return _data->size();
+  template <typename TKey>
+  FORCE_INLINE JsonVariant set(const TKey& key) const {
+    return set_impl(makeString(key));
   }
 
-  bool isNull() const {
-    return _data == 0;
+  FORCE_INLINE JsonVariant set(StringInMemoryPool key) const {
+    return set_impl(key);
+  }
+
+  FORCE_INLINE JsonVariant set(ZeroTerminatedRamStringConst key) const {
+    return set_impl(key);
   }
 
   template <typename Visitor>
-  void visit(Visitor& visitor) const {
-    if (_data)
-      visitor.acceptObject(*this);
-    else
-      return visitor.acceptNull();
+  FORCE_INLINE void accept(Visitor& visitor) const {
+    JsonObjectConst(_data).accept(visitor);
   }
 
  private:
   template <typename TStringRef>
-  bool containsKey_impl(TStringRef key) const {
-    return findKey<TStringRef>(key) != end();
+  FORCE_INLINE JsonVariant get_impl(TStringRef key) const {
+    return JsonVariant(_memoryPool, objectGet(_data, key));
+  }
+
+  template <typename TKey>
+  FORCE_INLINE JsonVariant set_impl(TKey key) const {
+    return JsonVariant(_memoryPool, objectSet(_data, key, _memoryPool));
   }
 
   template <typename TStringRef>
-  JsonArray createNestedArray_impl(TStringRef key);
-
-  template <typename TStringRef>
-  JsonObject createNestedObject_impl(TStringRef key);
-
-  // Returns the list node that matches the specified key.
-  template <typename TStringRef>
-  iterator findKey(TStringRef key) {
-    iterator it;
-    for (it = begin(); it != end(); ++it) {
-      if (Internals::makeString(key).equals(it->key)) break;
-    }
-    return it;
-  }
-  template <typename TStringRef>
-  const_iterator findKey(TStringRef key) const {
-    return const_cast<JsonObject*>(this)->findKey<TStringRef>(key);
+  FORCE_INLINE void remove_impl(TStringRef key) const {
+    objectRemove(_data, objectFindSlot(_data, key), _memoryPool);
   }
 
-  template <typename TStringRef, typename TValue>
-  typename Internals::JsonVariantAs<TValue>::type get_impl(
-      TStringRef key) const {
-    const_iterator it = findKey<TStringRef>(key);
-    return it != end() ? it->value.as<TValue>()
-                       : Internals::JsonVariantDefault<TValue>::get();
-  }
-
-  template <typename TStringRef, typename TValue>
-  bool is_impl(TStringRef key) const {
-    const_iterator it = findKey<TStringRef>(key);
-    return it != end() ? it->value.is<TValue>() : false;
-  }
-
-  template <typename TStringRef>
-  void remove_impl(TStringRef key) {
-    if (!_data) return;
-    _data->remove(findKey<TStringRef>(key));
-  }
-
-  template <typename TStringRef, typename TValueRef>
-  bool set_impl(TStringRef key, TValueRef value) {
-    if (!_data) return false;
-
-    // ignore null key
-    if (Internals::makeString(key).is_null()) return false;
-
-    // search a matching key
-    iterator it = findKey<TStringRef>(key);
-    if (it == end()) {
-      // add the key
-      it = _data->add();
-      if (it == end()) return false;
-      bool key_ok =
-          Internals::ValueSaver<TStringRef>::save(_data->_buffer, it->key, key);
-      if (!key_ok) return false;
-    }
-
-    // save the value
-    return Internals::ValueSaver<TValueRef>::save(_data->_buffer, it->value,
-                                                  value);
-  }
-
-  Internals::JsonObjectData* _data;
+  MemoryPool* _memoryPool;
 };
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/JsonObjectData.hpp

@@ -1,26 +0,0 @@
-// ArduinoJson - arduinojson.org
-// Copyright Benoit Blanchon 2014-2018
-// MIT License
-
-#pragma once
-
-#include "Data/List.hpp"
-#include "Data/ValueSaver.hpp"
-#include "JsonPair.hpp"
-#include "Memory/JsonBufferAllocated.hpp"
-#include "Polyfills/type_traits.hpp"
-
-// Returns the size (in bytes) of an object with n elements.
-// Can be very handy to determine the size of a StaticJsonBuffer.
-#define JSON_OBJECT_SIZE(NUMBER_OF_ELEMENTS)        \
-  (sizeof(ArduinoJson::Internals::JsonObjectData) + \
-   (NUMBER_OF_ELEMENTS) *                           \
-       sizeof(ArduinoJson::Internals::JsonObjectData::node_type))
-
-namespace ArduinoJson {
-namespace Internals {
-struct JsonObjectData : List<JsonPair>, JsonBufferAllocated {
-  explicit JsonObjectData(JsonBuffer* buf) throw() : List<JsonPair>(buf) {}
-};
-}  // namespace Internals
-}  // namespace ArduinoJson

src/ArduinoJson/JsonObjectImpl.hpp

@@ -7,31 +7,15 @@
 #include "JsonArray.hpp"
 #include "JsonObject.hpp"
 
-namespace ArduinoJson {
+namespace ARDUINOJSON_NAMESPACE {
 
 template <typename TString>
-inline JsonArray JsonObject::createNestedArray(const TString& key) {
-  return createNestedArray_impl<const TString&>(key);
+inline JsonArray JsonObject::createNestedArray(const TString& key) const {
+  return set(key).template to<JsonArray>();
 }
 
 template <typename TString>
-inline JsonArray JsonObject::createNestedArray(TString* key) {
-  return createNestedArray_impl<TString*>(key);
+inline JsonArray JsonObject::createNestedArray(TString* key) const {
+  return set(key).template to<JsonArray>();
 }
-
-template <typename TStringRef>
-inline JsonArray JsonObject::createNestedArray_impl(TStringRef key) {
-  if (!_data) return JsonArray();
-  JsonArray array(_data->_buffer);
-  if (!array.isNull()) set(key, array);
-  return array;
-}
-
-template <typename TStringRef>
-inline JsonObject JsonObject::createNestedObject_impl(TStringRef key) {
-  if (!_data) return JsonObject();
-  JsonObject object(_data->_buffer);
-  if (!object.isNull()) set(key, object);
-  return object;
-}
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/JsonObjectIterator.hpp

@@ -0,0 +1,124 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2018
+// MIT License
+
+#pragma once
+
+#include "Data/SlotFunctions.hpp"
+#include "JsonPair.hpp"
+
+namespace ARDUINOJSON_NAMESPACE {
+
+class JsonPairPtr {
+ public:
+  JsonPairPtr(MemoryPool *memoryPool, VariantSlot *slot)
+      : _pair(memoryPool, slot) {}
+
+  const JsonPair *operator->() const {
+    return &_pair;
+  }
+
+  const JsonPair &operator*() const {
+    return _pair;
+  }
+
+ private:
+  JsonPair _pair;
+};
+
+class JsonObjectIterator {
+ public:
+  JsonObjectIterator() : _slot(0) {}
+
+  explicit JsonObjectIterator(MemoryPool *memoryPool, VariantSlot *slot)
+      : _memoryPool(memoryPool), _slot(slot) {}
+
+  JsonPair operator*() const {
+    return JsonPair(_memoryPool, _slot);
+  }
+  JsonPairPtr operator->() {
+    return JsonPairPtr(_memoryPool, _slot);
+  }
+
+  bool operator==(const JsonObjectIterator &other) const {
+    return _slot == other._slot;
+  }
+
+  bool operator!=(const JsonObjectIterator &other) const {
+    return _slot != other._slot;
+  }
+
+  JsonObjectIterator &operator++() {
+    if (_slot) _slot = _slot->next;
+    return *this;
+  }
+
+  JsonObjectIterator &operator+=(size_t distance) {
+    _slot = slotAdvance(_slot, distance);
+    return *this;
+  }
+
+  VariantSlot *internal() {
+    return _slot;
+  }
+
+ private:
+  MemoryPool *_memoryPool;
+  VariantSlot *_slot;
+};
+
+class JsonPairConstPtr {
+ public:
+  JsonPairConstPtr(const VariantSlot *slot) : _pair(slot) {}
+
+  const JsonPairConst *operator->() const {
+    return &_pair;
+  }
+
+  const JsonPairConst &operator*() const {
+    return _pair;
+  }
+
+ private:
+  JsonPairConst _pair;
+};
+
+class JsonObjectConstIterator {
+ public:
+  JsonObjectConstIterator() : _slot(0) {}
+
+  explicit JsonObjectConstIterator(const VariantSlot *slot) : _slot(slot) {}
+
+  JsonPairConst operator*() const {
+    return JsonPairConst(_slot);
+  }
+  JsonPairConstPtr operator->() {
+    return JsonPairConstPtr(_slot);
+  }
+
+  bool operator==(const JsonObjectConstIterator &other) const {
+    return _slot == other._slot;
+  }
+
+  bool operator!=(const JsonObjectConstIterator &other) const {
+    return _slot != other._slot;
+  }
+
+  JsonObjectConstIterator &operator++() {
+    if (_slot) _slot = _slot->next;
+    return *this;
+  }
+
+  JsonObjectConstIterator &operator+=(size_t distance) {
+    _slot = slotAdvance(_slot, distance);
+    return *this;
+  }
+
+  const VariantSlot *internal() {
+    return _slot;
+  }
+
+ private:
+  const VariantSlot *_slot;
+};
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/JsonObjectSubscript.hpp

@@ -13,20 +13,24 @@
 #pragma warning(disable : 4522)
 #endif
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 template <typename TStringRef>
 class JsonObjectSubscript
-    : public JsonVariantBase<JsonObjectSubscript<TStringRef> > {
+    : public JsonVariantBase<JsonObjectSubscript<TStringRef> >,
+      public Visitable {
   typedef JsonObjectSubscript<TStringRef> this_type;
 
  public:
   FORCE_INLINE JsonObjectSubscript(JsonObject object, TStringRef key)
       : _object(object), _key(key) {}
 
+  operator JsonVariantConst() const {
+    return get_impl();
+  }
+
   FORCE_INLINE this_type &operator=(const this_type &src) {
-    _object.set(_key, src);
+    set_impl().set(src);
     return *this;
   }
 
@@ -38,7 +42,7 @@ class JsonObjectSubscript
   template <typename TValue>
   FORCE_INLINE typename enable_if<!is_array<TValue>::value, this_type &>::type
   operator=(const TValue &src) {
-    _object.set(_key, src);
+    set_impl().set(src);
     return *this;
   }
   //
@@ -46,22 +50,27 @@ class JsonObjectSubscript
   // TValue = char*, const char*, const FlashStringHelper*
   template <typename TValue>
   FORCE_INLINE this_type &operator=(TValue *src) {
-    _object.set(_key, src);
+    set_impl().set(src);
     return *this;
   }
 
   FORCE_INLINE bool isNull() const {
-    return !_object.containsKey(_key);
+    return get_impl().isNull();
   }
 
   template <typename TValue>
   FORCE_INLINE typename JsonVariantAs<TValue>::type as() const {
-    return _object.get<TValue>(_key);
+    return get_impl().template as<TValue>();
   }
 
   template <typename TValue>
   FORCE_INLINE bool is() const {
-    return _object.is<TValue>(_key);
+    return get_impl().template is<TValue>();
+  }
+
+  template <typename TValue>
+  FORCE_INLINE typename JsonVariantTo<TValue>::type to() {
+    return set_impl().template to<TValue>();
   }
 
   // Sets the specified value.
@@ -73,22 +82,30 @@ class JsonObjectSubscript
   template <typename TValue>
   FORCE_INLINE typename enable_if<!is_array<TValue>::value, bool>::type set(
       const TValue &value) {
-    return _object.set(_key, value);
+    return set_impl().set(value);
   }
   //
   // bool set(TValue);
   // TValue = char*, const char, const FlashStringHelper*
   template <typename TValue>
   FORCE_INLINE bool set(const TValue *value) {
-    return _object.set(_key, value);
+    return set_impl().set(value);
   }
 
   template <typename Visitor>
-  void visit(Visitor &visitor) const {
-    return _object.get<JsonVariant>(_key).visit(visitor);
+  void accept(Visitor &visitor) const {
+    return get_impl().accept(visitor);
   }
 
  private:
+  FORCE_INLINE JsonVariant get_impl() const {
+    return _object.get(_key);
+  }
+
+  FORCE_INLINE JsonVariant set_impl() const {
+    return _object.set(_key);
+  }
+
   JsonObject _object;
   TStringRef _key;
 };
@@ -96,37 +113,20 @@ class JsonObjectSubscript
 template <typename TImpl>
 template <typename TString>
 inline typename enable_if<IsString<TString>::value,
-                          const JsonObjectSubscript<const TString &> >::type
+                          JsonObjectSubscript<const TString &> >::type
     JsonVariantSubscripts<TImpl>::operator[](const TString &key) const {
   return impl()->template as<JsonObject>()[key];
 }
 
-template <typename TImpl>
-template <typename TString>
-inline typename enable_if<IsString<TString>::value,
-                          JsonObjectSubscript<const TString &> >::type
-    JsonVariantSubscripts<TImpl>::operator[](const TString &key) {
-  return impl()->template as<JsonObject>()[key];
-}
-
-template <typename TImpl>
-template <typename TString>
-inline typename enable_if<IsString<const TString *>::value,
-                          JsonObjectSubscript<const TString *> >::type
-    JsonVariantSubscripts<TImpl>::operator[](const TString *key) {
-  return impl()->template as<JsonObject>()[key];
-}
-
 template <typename TImpl>
 template <typename TString>
 inline typename enable_if<IsString<TString *>::value,
-                          const JsonObjectSubscript<const TString *> >::type
-    JsonVariantSubscripts<TImpl>::operator[](const TString *key) const {
+                          JsonObjectSubscript<TString *> >::type
+    JsonVariantSubscripts<TImpl>::operator[](TString *key) const {
   return impl()->template as<JsonObject>()[key];
 }
 
-}  // namespace Internals
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE
 
 #ifdef _MSC_VER
 #pragma warning(pop)

src/ArduinoJson/JsonPair.hpp

@@ -4,13 +4,50 @@
 
 #pragma once
 
+#include "JsonKey.hpp"
 #include "JsonVariant.hpp"
 
-namespace ArduinoJson {
-
+namespace ARDUINOJSON_NAMESPACE {
 // A key value pair for JsonObjectData.
-struct JsonPair {
-  const char* key;
-  JsonVariant value;
+class JsonPair {
+ public:
+  JsonPair(MemoryPool* memoryPool, VariantSlot* slot) : _key(slot) {
+    if (slot) {
+      _value = JsonVariant(memoryPool, &slot->value);
+    }
+  }
+
+  JsonKey key() const {
+    return _key;
+  }
+
+  JsonVariant value() const {
+    return _value;
+  }
+
+ private:
+  JsonKey _key;
+  JsonVariant _value;
 };
-}  // namespace ArduinoJson
+
+class JsonPairConst {
+ public:
+  JsonPairConst(const VariantSlot* slot) : _key(slot) {
+    if (slot) {
+      _value = JsonVariantConst(&slot->value);
+    }
+  }
+
+  JsonKey key() const {
+    return _key;
+  }
+
+  JsonVariantConst value() const {
+    return _value;
+  }
+
+ private:
+  JsonKey _key;
+  JsonVariantConst _value;
+};
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/JsonVariant.hpp

@@ -7,190 +7,28 @@
 #include <stddef.h>
 #include <stdint.h>  // for uint8_t
 
-#include "Data/JsonVariantContent.hpp"
-#include "Data/JsonVariantDefault.hpp"
-#include "Data/JsonVariantType.hpp"
+#include "Data/JsonVariantData.hpp"
+#include "Data/VariantAs.hpp"
+#include "Data/VariantFunctions.hpp"
+#include "JsonVariant.hpp"
 #include "JsonVariantBase.hpp"
+#include "Memory/MemoryPool.hpp"
+#include "Numbers/parseFloat.hpp"
+#include "Numbers/parseInteger.hpp"
 #include "Polyfills/type_traits.hpp"
-#include "Serialization/DynamicStringWriter.hpp"
-#include "SerializedValue.hpp"
+#include "Visitable.hpp"
 
-namespace ArduinoJson {
+namespace ARDUINOJSON_NAMESPACE {
 
 // Forward declarations.
 class JsonArray;
 class JsonObject;
 
-// A variant that can be a any value serializable to a JSON value.
-//
-// It can be set to:
-// - a boolean
-// - a char, short, int or a long (signed or unsigned)
-// - a string (const char*)
-// - a reference to a JsonArray or JsonObject
-class JsonVariant : public Internals::JsonVariantBase<JsonVariant> {
+// Contains the methods shared by JsonVariant and JsonVariantConst
+template <typename TData>
+class JsonVariantProxy {
  public:
-  // Creates an uninitialized JsonVariant
-  JsonVariant() : _type(Internals::JSON_UNDEFINED) {}
-
-  // Create a JsonVariant containing a boolean value.
-  // It will be serialized as "true" or "false" in JSON.
-  JsonVariant(bool value) {
-    using namespace Internals;
-    _type = JSON_BOOLEAN;
-    _content.asInteger = static_cast<JsonUInt>(value);
-  }
-
-  // Create a JsonVariant containing a floating point value.
-  // JsonVariant(double value);
-  // JsonVariant(float value);
-  template <typename T>
-  JsonVariant(T value,
-              typename Internals::enable_if<
-                  Internals::is_floating_point<T>::value>::type * = 0) {
-    using namespace Internals;
-    _type = JSON_FLOAT;
-    _content.asFloat = static_cast<JsonFloat>(value);
-  }
-
-  // Create a JsonVariant containing an integer value.
-  // JsonVariant(char)
-  // JsonVariant(signed short)
-  // JsonVariant(signed int)
-  // JsonVariant(signed long)
-  // JsonVariant(signed char)
-  template <typename T>
-  JsonVariant(
-      T value,
-      typename Internals::enable_if<Internals::is_integral<T>::value &&
-                                    Internals::is_signed<T>::value>::type * =
-          0) {
-    using namespace Internals;
-    if (value >= 0) {
-      _type = JSON_POSITIVE_INTEGER;
-      _content.asInteger = static_cast<JsonUInt>(value);
-    } else {
-      _type = JSON_NEGATIVE_INTEGER;
-      _content.asInteger = ~static_cast<JsonUInt>(value) + 1;
-    }
-  }
-  // JsonVariant(unsigned short)
-  // JsonVariant(unsigned int)
-  // JsonVariant(unsigned long)
-  template <typename T>
-  JsonVariant(
-      T value,
-      typename Internals::enable_if<Internals::is_integral<T>::value &&
-                                    Internals::is_unsigned<T>::value>::type * =
-          0) {
-    using namespace Internals;
-    _type = JSON_POSITIVE_INTEGER;
-    _content.asInteger = static_cast<JsonUInt>(value);
-  }
-
-  // Create a JsonVariant containing a string.
-  // JsonVariant(const char*);
-  // JsonVariant(const signed char*);
-  // JsonVariant(const unsigned char*);
-  template <typename TChar>
-  JsonVariant(const TChar *value,
-              typename Internals::enable_if<sizeof(TChar) == 1>::type * = 0) {
-    _type = Internals::JSON_STRING;
-    _content.asString = reinterpret_cast<const char *>(value);
-  }
-
-  // Create a JsonVariant containing an unparsed string
-  JsonVariant(Internals::SerializedValue<const char *> value) {
-    _type = Internals::JSON_UNPARSED;
-    _content.asRaw.data = value.data();
-    _content.asRaw.size = value.size();
-  }
-
-  JsonVariant(JsonArray array);
-  JsonVariant(JsonObject object);
-
-  // Get the variant as the specified type.
-  //
-  // char as<char>() const;
-  // signed char as<signed char>() const;
-  // signed short as<signed short>() const;
-  // signed int as<signed int>() const;
-  // signed long as<signed long>() const;
-  // unsigned char as<unsigned char>() const;
-  // unsigned short as<unsigned short>() const;
-  // unsigned int as<unsigned int>() const;
-  // unsigned long as<unsigned long>() const;
-  template <typename T>
-  const typename Internals::enable_if<Internals::is_integral<T>::value, T>::type
-  as() const {
-    return variantAsInteger<T>();
-  }
-  // bool as<bool>() const
-  template <typename T>
-  const typename Internals::enable_if<Internals::is_same<T, bool>::value,
-                                      T>::type
-  as() const {
-    return variantAsInteger<int>() != 0;
-  }
-  //
-  // double as<double>() const;
-  // float as<float>() const;
-  template <typename T>
-  const typename Internals::enable_if<Internals::is_floating_point<T>::value,
-                                      T>::type
-  as() const {
-    return variantAsFloat<T>();
-  }
-  //
-  // const char* as<const char*>() const;
-  // const char* as<char*>() const;
-  template <typename T>
-  typename Internals::enable_if<Internals::is_same<T, const char *>::value ||
-                                    Internals::is_same<T, char *>::value,
-                                const char *>::type
-  as() const {
-    return variantAsString();
-  }
-  //
-  // std::string as<std::string>() const;
-  // String as<String>() const;
-  template <typename T>
-  typename Internals::enable_if<Internals::IsWriteableString<T>::value, T>::type
-  as() const {
-    const char *cstr = variantAsString();
-    if (cstr) return T(cstr);
-    T s;
-    serializeJson(*this, s);
-    return s;
-  }
-  //
-  // JsonArray as<JsonArray>() const;
-  // const JsonArray as<const JsonArray>() const;
-  template <typename T>
-  typename Internals::enable_if<
-      Internals::is_same<typename Internals::remove_const<T>::type,
-                         JsonArray>::value,
-      JsonArray>::type
-  as() const;
-  //
-  // JsonObject as<JsonObject>() const;
-  // const JsonObject as<const JsonObject>() const;
-  template <typename T>
-  typename Internals::enable_if<
-      Internals::is_same<typename Internals::remove_const<T>::type,
-                         JsonObject>::value,
-      T>::type
-  as() const;
-  //
-  // JsonVariant as<JsonVariant> const;
-  template <typename T>
-  typename Internals::enable_if<Internals::is_same<T, JsonVariant>::value,
-                                T>::type
-  as() const {
-    return *this;
-  }
-
-  // Tells weither the variant has the specified type.
+  // Tells wether the variant has the specified type.
   // Returns true if the variant has type type T, false otherwise.
   //
   // bool is<char>() const;
@@ -203,122 +41,290 @@ class JsonVariant : public Internals::JsonVariantBase<JsonVariant> {
   // bool is<unsigned int>() const;
   // bool is<unsigned long>() const;
   template <typename T>
-  typename Internals::enable_if<Internals::is_integral<T>::value, bool>::type
-  is() const {
-    return variantIsInteger();
+  FORCE_INLINE typename enable_if<is_integral<T>::value, bool>::type is()
+      const {
+    return variantIsInteger(_data);
   }
   //
   // bool is<double>() const;
   // bool is<float>() const;
   template <typename T>
-  typename Internals::enable_if<Internals::is_floating_point<T>::value,
-                                bool>::type
-  is() const {
-    return variantIsFloat();
+  FORCE_INLINE typename enable_if<is_floating_point<T>::value, bool>::type is()
+      const {
+    return variantIsFloat(_data);
   }
   //
   // bool is<bool>() const
   template <typename T>
-  typename Internals::enable_if<Internals::is_same<T, bool>::value, bool>::type
-  is() const {
-    return variantIsBoolean();
+  FORCE_INLINE typename enable_if<is_same<T, bool>::value, bool>::type is()
+      const {
+    return _data && _data->type == JSON_BOOLEAN;
   }
   //
   // bool is<const char*>() const;
   // bool is<char*>() const;
+  // bool is<std::string>() const;
+  // bool is<String>() const;
   template <typename T>
-  typename Internals::enable_if<Internals::is_same<T, const char *>::value ||
-                                    Internals::is_same<T, char *>::value,
-                                bool>::type
+  FORCE_INLINE typename enable_if<is_same<T, const char *>::value ||
+                                      is_same<T, char *>::value ||
+                                      IsWriteableString<T>::value,
+                                  bool>::type
   is() const {
-    return variantIsString();
+    return variantIsString(_data);
   }
   //
   // bool is<JsonArray> const;
   // bool is<const JsonArray> const;
   template <typename T>
-  typename Internals::enable_if<
-      Internals::is_same<typename Internals::remove_const<T>::type,
-                         JsonArray>::value,
-      bool>::type
+  FORCE_INLINE typename enable_if<
+      is_same<typename remove_const<T>::type, JsonArray>::value, bool>::type
   is() const {
-    return variantIsArray();
+    return variantIsArray(_data);
   }
   //
   // bool is<JsonObject> const;
   // bool is<const JsonObject> const;
   template <typename T>
-  typename Internals::enable_if<
-      Internals::is_same<typename Internals::remove_const<T>::type,
-                         JsonObject>::value,
-      bool>::type
+  FORCE_INLINE typename enable_if<
+      is_same<typename remove_const<T>::type, JsonObject>::value, bool>::type
   is() const {
-    return variantIsObject();
+    return variantIsObject(_data);
   }
 
-  // Returns true if the variant has a value
-  bool isNull() const {
-    return _type == Internals::JSON_UNDEFINED;
+  FORCE_INLINE bool isNull() const {
+    return variantIsNull(_data);
+  }
+
+  FORCE_INLINE bool isInvalid() const {
+    return _data == 0;
+  }
+
+  size_t size() const {
+    return objectSize(variantAsObject(_data)) +
+           arraySize(variantAsArray(_data));
+  }
+
+ protected:
+  JsonVariantProxy(TData *data) : _data(data) {}
+  TData *_data;
+};
+
+// A variant that can be a any value serializable to a JSON value.
+//
+// It can be set to:
+// - a boolean
+// - a char, short, int or a long (signed or unsigned)
+// - a string (const char*)
+// - a reference to a JsonArray or JsonObject
+class JsonVariant : public JsonVariantProxy<JsonVariantData>,
+                    public JsonVariantBase<JsonVariant>,
+                    public Visitable {
+  typedef JsonVariantProxy<JsonVariantData> proxy_type;
+  friend class JsonVariantConst;
+
+ public:
+  // Intenal use only
+  FORCE_INLINE JsonVariant(MemoryPool *memoryPool, JsonVariantData *data)
+      : proxy_type(data), _memoryPool(memoryPool) {}
+
+  // Creates an uninitialized JsonVariant
+  FORCE_INLINE JsonVariant() : proxy_type(0), _memoryPool(0) {}
+
+  // set(bool value)
+  FORCE_INLINE bool set(bool value) const {
+    return variantSetBoolean(_data, value, _memoryPool);
+  }
+
+  // set(double value);
+  // set(float value);
+  template <typename T>
+  FORCE_INLINE bool set(
+      T value,
+      typename enable_if<is_floating_point<T>::value>::type * = 0) const {
+    return variantSetFloat(_data, static_cast<JsonFloat>(value), _memoryPool);
+  }
+
+  // set(char)
+  // set(signed short)
+  // set(signed int)
+  // set(signed long)
+  // set(signed char)
+  template <typename T>
+  FORCE_INLINE bool set(
+      T value,
+      typename enable_if<is_integral<T>::value && is_signed<T>::value>::type * =
+          0) const {
+    return variantSetSignedInteger(_data, value, _memoryPool);
+  }
+
+  // set(unsigned short)
+  // set(unsigned int)
+  // set(unsigned long)
+  template <typename T>
+  FORCE_INLINE bool set(
+      T value, typename enable_if<is_integral<T>::value &&
+                                  is_unsigned<T>::value>::type * = 0) const {
+    return variantSetUnsignedInteger(_data, static_cast<JsonUInt>(value),
+                                     _memoryPool);
+  }
+
+  // set(SerializedValue<const char *>)
+  FORCE_INLINE bool set(SerializedValue<const char *> value) const {
+    return variantSetLinkedRaw(_data, value, _memoryPool);
+  }
+
+  // set(SerializedValue<std::string>)
+  // set(SerializedValue<String>)
+  // set(SerializedValue<const __FlashStringHelper*>)
+  template <typename T>
+  FORCE_INLINE bool set(
+      SerializedValue<T> value,
+      typename enable_if<!is_same<const char *, T>::value>::type * = 0) const {
+    return variantSetOwnedRaw(_data, value, _memoryPool);
+  }
+
+  // set(const std::string&)
+  // set(const String&)
+  template <typename T>
+  FORCE_INLINE bool set(
+      const T &value,
+      typename enable_if<IsString<T>::value>::type * = 0) const {
+    return variantSetString(_data, makeString(value), _memoryPool);
+  }
+
+  // set(char*)
+  template <typename T>
+  FORCE_INLINE bool set(
+      T *value, typename enable_if<IsString<T *>::value>::type * = 0) const {
+    return variantSetString(_data, makeString(value), _memoryPool);
+  }
+
+  // set(const char*);
+  FORCE_INLINE bool set(const char *value) const {
+    return variantSetString(_data, value, _memoryPool);
+  }
+
+  // for internal use only
+  FORCE_INLINE bool set(StringInMemoryPool value) const {
+    return variantSetOwnedString(_data, value.slot(), _memoryPool);
+  }
+  FORCE_INLINE bool set(ZeroTerminatedRamStringConst value) const {
+    return variantSetString(_data, value.c_str(), _memoryPool);
+  }
+
+  bool set(JsonVariantConst value) const;
+  bool set(JsonVariant value) const;
+
+  FORCE_INLINE bool set(JsonArray array) const;
+  FORCE_INLINE bool set(const JsonArraySubscript &) const;
+  FORCE_INLINE bool set(JsonObject object) const;
+  template <typename TString>
+  FORCE_INLINE bool set(const JsonObjectSubscript<TString> &) const;
+
+  // Get the variant as the specified type.
+  //
+  // std::string as<std::string>() const;
+  // String as<String>() const;
+  template <typename T>
+  FORCE_INLINE typename enable_if<!is_same<T, JsonArray>::value &&
+                                      !is_same<T, JsonObject>::value &&
+                                      !is_same<T, JsonVariant>::value,
+                                  typename JsonVariantAs<T>::type>::type
+  as() const {
+    return variantAs<T>(_data);
+  }
+  //
+  // JsonArray as<JsonArray>() const;
+  // const JsonArray as<const JsonArray>() const;
+  template <typename T>
+  FORCE_INLINE typename enable_if<is_same<T, JsonArray>::value, T>::type as()
+      const;
+  //
+  // JsonObject as<JsonObject>() const;
+  // const JsonObject as<const JsonObject>() const;
+  template <typename T>
+  FORCE_INLINE typename enable_if<is_same<T, JsonObject>::value, T>::type as()
+      const;
+  //
+  // JsonVariant as<JsonVariant> const;
+  template <typename T>
+  FORCE_INLINE typename enable_if<is_same<T, JsonVariant>::value, T>::type as()
+      const {
+    return *this;
   }
 
   template <typename Visitor>
-  void visit(Visitor &visitor) const {
-    using namespace Internals;
-    switch (_type) {
-      case JSON_FLOAT:
-        return visitor.acceptFloat(_content.asFloat);
+  void accept(Visitor &visitor) const;
 
-      case JSON_ARRAY:
-        return visitor.acceptArray(_content.asArray);
-
-      case JSON_OBJECT:
-        return visitor.acceptObject(_content.asObject);
-
-      case JSON_STRING:
-        return visitor.acceptString(_content.asString);
-
-      case JSON_UNPARSED:
-        return visitor.acceptRawJson(_content.asRaw.data, _content.asRaw.size);
-
-      case JSON_NEGATIVE_INTEGER:
-        return visitor.acceptNegativeInteger(_content.asInteger);
-
-      case JSON_POSITIVE_INTEGER:
-        return visitor.acceptPositiveInteger(_content.asInteger);
-
-      case JSON_BOOLEAN:
-        return visitor.acceptBoolean(_content.asInteger != 0);
-
-      default:  // JSON_UNDEFINED
-        return visitor.acceptNull();
-    }
+  FORCE_INLINE bool operator==(JsonVariant lhs) const {
+    return variantEquals(_data, lhs._data);
   }
 
+  FORCE_INLINE bool operator!=(JsonVariant lhs) const {
+    return !variantEquals(_data, lhs._data);
+  }
+
+  // Change the type of the variant
+  //
+  // JsonArray to<JsonArray>()
+  template <typename T>
+  typename enable_if<is_same<T, JsonArray>::value, JsonArray>::type to() const;
+  //
+  // JsonObject to<JsonObject>()
+  template <typename T>
+  typename enable_if<is_same<T, JsonObject>::value, JsonObject>::type to()
+      const;
+  //
+  // JsonObject to<JsonVariant>()
+  template <typename T>
+  typename enable_if<is_same<T, JsonVariant>::value, JsonVariant>::type to()
+      const;
+
  private:
-  JsonArray variantAsArray() const;
-  JsonObject variantAsObject() const;
-  const char *variantAsString() const;
-  template <typename T>
-  T variantAsFloat() const;
-  template <typename T>
-  T variantAsInteger() const;
-  bool variantIsBoolean() const;
-  bool variantIsFloat() const;
-  bool variantIsInteger() const;
-  bool variantIsArray() const {
-    return _type == Internals::JSON_ARRAY;
-  }
-  bool variantIsObject() const {
-    return _type == Internals::JSON_OBJECT;
-  }
-  bool variantIsString() const {
-    return _type == Internals::JSON_STRING;
-  }
-
-  // The current type of the variant
-  Internals::JsonVariantType _type;
-
-  // The various alternatives for the value of the variant.
-  Internals::JsonVariantContent _content;
+  MemoryPool *_memoryPool;
 };
-}  // namespace ArduinoJson
+
+class JsonVariantConst : public JsonVariantProxy<const JsonVariantData>,
+                         public JsonVariantBase<JsonVariantConst>,
+                         public Visitable {
+  typedef JsonVariantProxy<const JsonVariantData> proxy_type;
+  friend class JsonVariant;
+
+ public:
+  JsonVariantConst() : proxy_type(0) {}
+  JsonVariantConst(const JsonVariantData *data) : proxy_type(data) {}
+  JsonVariantConst(JsonVariant var) : proxy_type(var._data) {}
+
+  template <typename Visitor>
+  void accept(Visitor &visitor) const;
+
+  // Get the variant as the specified type.
+  //
+  template <typename T>
+  FORCE_INLINE typename JsonVariantConstAs<T>::type as() const {
+    return variantAs<typename JsonVariantConstAs<T>::type>(_data);
+  }
+
+  FORCE_INLINE JsonVariantConst operator[](size_t index) const;
+
+  //
+  // const JsonVariantConst operator[](TKey) const;
+  // TKey = const std::string&, const String&
+  template <typename TString>
+  FORCE_INLINE
+      typename enable_if<IsString<TString>::value, JsonVariantConst>::type
+      operator[](const TString &key) const {
+    return JsonVariantConst(objectGet(variantAsObject(_data), makeString(key)));
+  }
+  //
+  // JsonVariantConst operator[](TKey);
+  // TKey = const char*, const char[N], const FlashStringHelper*
+  template <typename TString>
+  FORCE_INLINE
+      typename enable_if<IsString<TString *>::value, JsonVariantConst>::type
+      operator[](TString *key) const {
+    return JsonVariantConst(objectGet(variantAsObject(_data), makeString(key)));
+  }
+};
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/JsonVariantBase.hpp

@@ -9,14 +9,11 @@
 #include "JsonVariantOr.hpp"
 #include "JsonVariantSubscripts.hpp"
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 template <typename TImpl>
 class JsonVariantBase : public JsonVariantCasts<TImpl>,
                         public JsonVariantComparisons<TImpl>,
                         public JsonVariantOr<TImpl>,
-                        public JsonVariantSubscripts<TImpl>,
-                        public JsonVariantTag {};
-}  // namespace Internals
-}  // namespace ArduinoJson
+                        public JsonVariantSubscripts<TImpl> {};
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/JsonVariantCasts.hpp

@@ -7,8 +7,7 @@
 #include "Data/JsonVariantAs.hpp"
 #include "Polyfills/attributes.hpp"
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 template <typename TImpl>
 class JsonVariantCasts {
@@ -23,5 +22,4 @@ class JsonVariantCasts {
     return static_cast<const TImpl *>(this);
   }
 };
-}  // namespace Internals
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/JsonVariantComparisons.hpp

@@ -4,136 +4,158 @@
 
 #pragma once
 
-#include "Data/IsVariant.hpp"
-#include "Polyfills/type_traits.hpp"
-#include "Strings/StringTypes.hpp"
+#include "JsonVariant.hpp"
 
-namespace ArduinoJson {
-class JsonArray;
-class JsonObject;
+namespace ARDUINOJSON_NAMESPACE {
+template <typename T>
+struct is_simple_value {
+  static const bool value = is_integral<T>::value ||
+                            is_floating_point<T>::value ||
+                            is_same<T, bool>::value;
+};
 
-namespace Internals {
-
-template <typename TImpl>
+template <typename TVariant>
 class JsonVariantComparisons {
  public:
-  template <typename TComparand>
-  friend bool operator==(const JsonVariantComparisons &variant,
-                         TComparand comparand) {
-    return variant.equals(comparand);
-  }
-
-  template <typename TComparand>
-  friend typename enable_if<!IsVariant<TComparand>::value, bool>::type
-  operator==(TComparand comparand, const JsonVariantComparisons &variant) {
-    return variant.equals(comparand);
-  }
-
-  template <typename TComparand>
-  friend bool operator!=(const JsonVariantComparisons &variant,
-                         TComparand comparand) {
-    return !variant.equals(comparand);
-  }
-
-  template <typename TComparand>
-  friend typename enable_if<!IsVariant<TComparand>::value, bool>::type
-  operator!=(TComparand comparand, const JsonVariantComparisons &variant) {
-    return !variant.equals(comparand);
-  }
-
-  template <typename TComparand>
-  friend bool operator<=(const JsonVariantComparisons &left, TComparand right) {
-    return left.as<TComparand>() <= right;
-  }
-
-  template <typename TComparand>
-  friend bool operator<=(TComparand comparand,
-                         const JsonVariantComparisons &variant) {
-    return comparand <= variant.as<TComparand>();
-  }
-
-  template <typename TComparand>
-  friend bool operator>=(const JsonVariantComparisons &variant,
-                         TComparand comparand) {
-    return variant.as<TComparand>() >= comparand;
-  }
-
-  template <typename TComparand>
-  friend bool operator>=(TComparand comparand,
-                         const JsonVariantComparisons &variant) {
-    return comparand >= variant.as<TComparand>();
-  }
-
-  template <typename TComparand>
-  friend bool operator<(const JsonVariantComparisons &varian,
-                        TComparand comparand) {
-    return varian.as<TComparand>() < comparand;
-  }
-
-  template <typename TComparand>
-  friend bool operator<(TComparand comparand,
-                        const JsonVariantComparisons &variant) {
-    return comparand < variant.as<TComparand>();
-  }
-
-  template <typename TComparand>
-  friend bool operator>(const JsonVariantComparisons &variant,
-                        TComparand comparand) {
-    return variant.as<TComparand>() > comparand;
-  }
-
-  template <typename TComparand>
-  friend bool operator>(TComparand comparand,
-                        const JsonVariantComparisons &variant) {
-    return comparand > variant.as<TComparand>();
-  }
-
- private:
-  const TImpl *impl() const {
-    return static_cast<const TImpl *>(this);
-  }
-
+  // const char* == TVariant
   template <typename T>
-  const typename JsonVariantAs<T>::type as() const {
-    return impl()->template as<T>();
+  friend typename enable_if<IsString<T *>::value, bool>::type operator==(
+      T *lhs, TVariant rhs) {
+    return makeString(lhs).equals(rhs.template as<const char *>());
   }
 
+  // std::string == TVariant
   template <typename T>
-  bool is() const {
-    return impl()->template is<T>();
+  friend typename enable_if<IsString<T>::value, bool>::type operator==(
+      const T &lhs, TVariant rhs) {
+    return makeString(lhs).equals(rhs.template as<const char *>());
   }
 
-  template <typename TString>
-  typename enable_if<IsString<TString>::value, bool>::type equals(
-      const TString &comparand) const {
-    return makeString(comparand).equals(as<const char *>());
+  // TVariant == const char*
+  template <typename T>
+  friend typename enable_if<IsString<T *>::value, bool>::type operator==(
+      TVariant lhs, T *rhs) {
+    return makeString(rhs).equals(lhs.template as<const char *>());
   }
 
-  template <typename TComparand>
-  typename enable_if<
-      !IsVariant<TComparand>::value && !IsString<TComparand>::value, bool>::type
-  equals(const TComparand &comparand) const {
-    return as<TComparand>() == comparand;
+  // TVariant == std::string
+  template <typename T>
+  friend typename enable_if<IsString<T>::value, bool>::type operator==(
+      TVariant lhs, const T &rhs) {
+    return makeString(rhs).equals(lhs.template as<const char *>());
   }
 
-  template <typename TVariant2>
-  bool equals(const JsonVariantComparisons<TVariant2> &right) const {
-    using namespace Internals;
-    if (is<bool>() && right.template is<bool>())
-      return as<bool>() == right.template as<bool>();
-    if (is<JsonInteger>() && right.template is<JsonInteger>())
-      return as<JsonInteger>() == right.template as<JsonInteger>();
-    if (is<JsonFloat>() && right.template is<JsonFloat>())
-      return as<JsonFloat>() == right.template as<JsonFloat>();
-    if (is<JsonArray>() && right.template is<JsonArray>())
-      return as<JsonArray>() == right.template as<JsonArray>();
-    if (is<JsonObject>() && right.template is<JsonObject>())
-      return as<JsonObject>() == right.template as<JsonObject>();
-    if (is<char *>() && right.template is<char *>())
-      return makeString(as<char *>()).equals(right.template as<char *>());
+  // bool/int/float == TVariant
+  template <typename T>
+  friend typename enable_if<is_simple_value<T>::value, bool>::type operator==(
+      const T &lhs, TVariant rhs) {
+    return lhs == rhs.template as<T>();
+  }
 
-    return false;
+  // TVariant == bool/int/float
+  template <typename T>
+  friend typename enable_if<is_simple_value<T>::value, bool>::type operator==(
+      TVariant lhs, const T &rhs) {
+    return lhs.template as<T>() == rhs;
+  }
+
+  // const char* != TVariant
+  template <typename T>
+  friend typename enable_if<IsString<T *>::value, bool>::type operator!=(
+      T *lhs, TVariant rhs) {
+    return !makeString(lhs).equals(rhs.template as<const char *>());
+  }
+
+  // std::string != TVariant
+  template <typename T>
+  friend typename enable_if<IsString<T>::value, bool>::type operator!=(
+      const T &lhs, TVariant rhs) {
+    return !makeString(lhs).equals(rhs.template as<const char *>());
+  }
+
+  // TVariant != const char*
+  template <typename T>
+  friend typename enable_if<IsString<T *>::value, bool>::type operator!=(
+      TVariant lhs, T *rhs) {
+    return !makeString(rhs).equals(lhs.template as<const char *>());
+  }
+
+  // TVariant != std::string
+  template <typename T>
+  friend typename enable_if<IsString<T>::value, bool>::type operator!=(
+      TVariant lhs, const T &rhs) {
+    return !makeString(rhs).equals(lhs.template as<const char *>());
+  }
+
+  // bool/int/float != TVariant
+  template <typename T>
+  friend typename enable_if<is_simple_value<T>::value, bool>::type operator!=(
+      const T &lhs, TVariant rhs) {
+    return lhs != rhs.template as<T>();
+  }
+
+  // TVariant != bool/int/float
+  template <typename T>
+  friend typename enable_if<is_simple_value<T>::value, bool>::type operator!=(
+      TVariant lhs, const T &rhs) {
+    return lhs.template as<T>() != rhs;
+  }
+
+  // bool/int/float < TVariant
+  template <typename T>
+  friend typename enable_if<is_simple_value<T>::value, bool>::type operator<(
+      const T &lhs, TVariant rhs) {
+    return lhs < rhs.template as<T>();
+  }
+
+  // TVariant < bool/int/float
+  template <typename T>
+  friend typename enable_if<is_simple_value<T>::value, bool>::type operator<(
+      TVariant lhs, const T &rhs) {
+    return lhs.template as<T>() < rhs;
+  }
+
+  // bool/int/float <= TVariant
+  template <typename T>
+  friend typename enable_if<is_simple_value<T>::value, bool>::type operator<=(
+      const T &lhs, TVariant rhs) {
+    return lhs <= rhs.template as<T>();
+  }
+
+  // TVariant <= bool/int/float
+  template <typename T>
+  friend typename enable_if<is_simple_value<T>::value, bool>::type operator<=(
+      TVariant lhs, const T &rhs) {
+    return lhs.template as<T>() <= rhs;
+  }
+
+  // bool/int/float > TVariant
+  template <typename T>
+  friend typename enable_if<is_simple_value<T>::value, bool>::type operator>(
+      const T &lhs, TVariant rhs) {
+    return lhs > rhs.template as<T>();
+  }
+
+  // TVariant > bool/int/float
+  template <typename T>
+  friend typename enable_if<is_simple_value<T>::value, bool>::type operator>(
+      TVariant lhs, const T &rhs) {
+    return lhs.template as<T>() > rhs;
+  }
+
+  // bool/int/float >= TVariant
+  template <typename T>
+  friend typename enable_if<is_simple_value<T>::value, bool>::type operator>=(
+      const T &lhs, TVariant rhs) {
+    return lhs >= rhs.template as<T>();
+  }
+
+  // TVariant >= bool/int/float
+  template <typename T>
+  friend typename enable_if<is_simple_value<T>::value, bool>::type operator>=(
+      TVariant lhs, const T &rhs) {
+    return lhs.template as<T>() >= rhs;
   }
 };
-}  // namespace Internals
-}  // namespace ArduinoJson
+
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/JsonVariantImpl.hpp

@@ -5,123 +5,119 @@
 #pragma once
 
 #include "Configuration.hpp"
-#include "JsonArrayData.hpp"
-#include "JsonObjectData.hpp"
 #include "JsonVariant.hpp"
-#include "Numbers/isFloat.hpp"
-#include "Numbers/isInteger.hpp"
 #include "Numbers/parseFloat.hpp"
 #include "Numbers/parseInteger.hpp"
 
 #include <string.h>  // for strcmp
 
-namespace ArduinoJson {
+namespace ARDUINOJSON_NAMESPACE {
 
-inline JsonVariant::JsonVariant(JsonArray array) {
-  if (!array.isNull()) {
-    _type = Internals::JSON_ARRAY;
-    _content.asArray = array._data;
-  } else {
-    _type = Internals::JSON_UNDEFINED;
-  }
+inline bool JsonVariant::set(JsonArray array) const {
+  return to<JsonArray>().copyFrom(array);
 }
 
-inline JsonVariant::JsonVariant(JsonObject object) {
-  if (!object.isNull()) {
-    _type = Internals::JSON_OBJECT;
-    _content.asObject = object._data;
-  } else {
-    _type = Internals::JSON_UNDEFINED;
-  }
+inline bool JsonVariant::set(const JsonArraySubscript& value) const {
+  return set(value.as<JsonVariant>());
+}
+
+inline bool JsonVariant::set(JsonObject object) const {
+  return to<JsonObject>().copyFrom(object);
+}
+
+template <typename TString>
+inline bool JsonVariant::set(const JsonObjectSubscript<TString>& value) const {
+  return set(value.template as<JsonVariant>());
+}
+
+inline bool JsonVariant::set(JsonVariantConst value) const {
+  return variantCopy(_data, value._data, _memoryPool);
+}
+
+inline bool JsonVariant::set(JsonVariant value) const {
+  return variantCopy(_data, value._data, _memoryPool);
 }
 
 template <typename T>
-inline typename Internals::enable_if<
-    Internals::is_same<typename Internals::remove_const<T>::type,
-                       JsonArray>::value,
-    JsonArray>::type
+inline typename enable_if<is_same<T, JsonArray>::value, T>::type
 JsonVariant::as() const {
-  return variantAsArray();
+  return JsonArray(_memoryPool, variantAsArray(_data));
 }
 
 template <typename T>
-inline typename Internals::enable_if<
-    Internals::is_same<typename Internals::remove_const<T>::type,
-                       JsonObject>::value,
-    T>::type
+inline typename enable_if<is_same<T, JsonObject>::value, T>::type
 JsonVariant::as() const {
-  return variantAsObject();
-}
-
-inline JsonArray JsonVariant::variantAsArray() const {
-  if (_type == Internals::JSON_ARRAY) return _content.asArray;
-  return JsonArray();
-}
-
-inline JsonObject JsonVariant::variantAsObject() const {
-  if (_type == Internals::JSON_OBJECT) return _content.asObject;
-  return JsonObject();
+  return JsonObject(_memoryPool, variantAsObject(_data));
 }
 
 template <typename T>
-inline T JsonVariant::variantAsInteger() const {
-  using namespace Internals;
-  switch (_type) {
-    case JSON_UNDEFINED:
-    case JSON_UNPARSED:
-      return 0;
-    case JSON_POSITIVE_INTEGER:
-    case JSON_BOOLEAN:
-      return T(_content.asInteger);
-    case JSON_NEGATIVE_INTEGER:
-      return T(~_content.asInteger + 1);
-    case JSON_STRING:
-      return parseInteger<T>(_content.asString);
-    default:
-      return T(_content.asFloat);
-  }
-}
-
-inline const char *JsonVariant::variantAsString() const {
-  using namespace Internals;
-  return _type == JSON_STRING ? _content.asString : NULL;
+inline typename enable_if<is_same<T, JsonArray>::value, JsonArray>::type
+JsonVariant::to() const {
+  return JsonArray(_memoryPool, variantToArray(_data, _memoryPool));
 }
 
 template <typename T>
-inline T JsonVariant::variantAsFloat() const {
-  using namespace Internals;
-  switch (_type) {
-    case JSON_UNDEFINED:
-    case JSON_UNPARSED:
-      return 0;
-    case JSON_POSITIVE_INTEGER:
-    case JSON_BOOLEAN:
-      return static_cast<T>(_content.asInteger);
+typename enable_if<is_same<T, JsonObject>::value, JsonObject>::type
+JsonVariant::to() const {
+  return JsonObject(_memoryPool, variantToObject(_data, _memoryPool));
+}
+
+template <typename T>
+typename enable_if<is_same<T, JsonVariant>::value, JsonVariant>::type
+JsonVariant::to() const {
+  variantSetNull(_data, _memoryPool);
+  return *this;
+}
+
+template <typename Visitor>
+inline void JsonVariant::accept(Visitor& visitor) const {
+  return JsonVariantConst(_data).accept(visitor);
+}
+
+template <typename Visitor>
+inline void JsonVariantConst::accept(Visitor& visitor) const {
+  if (!_data) return visitor.visitNull();
+
+  switch (_data->type) {
+    case JSON_FLOAT:
+      return visitor.visitFloat(_data->content.asFloat);
+
+    case JSON_ARRAY:
+      return visitor.visitArray(JsonArrayConst(&_data->content.asArray));
+
+    case JSON_OBJECT:
+      return visitor.visitObject(JsonObjectConst(&_data->content.asObject));
+
+    case JSON_LINKED_STRING:
+      return visitor.visitString(_data->content.asString);
+
+    case JSON_OWNED_STRING:
+      return visitor.visitString(_data->content.asOwnedString->value);
+
+    case JSON_OWNED_RAW:
+      return visitor.visitRawJson(_data->content.asOwnedRaw->value,
+                                  _data->content.asOwnedRaw->size);
+
+    case JSON_LINKED_RAW:
+      return visitor.visitRawJson(_data->content.asRaw.data,
+                                  _data->content.asRaw.size);
+
     case JSON_NEGATIVE_INTEGER:
-      return -static_cast<T>(_content.asInteger);
-    case JSON_STRING:
-      return parseFloat<T>(_content.asString);
+      return visitor.visitNegativeInteger(_data->content.asInteger);
+
+    case JSON_POSITIVE_INTEGER:
+      return visitor.visitPositiveInteger(_data->content.asInteger);
+
+    case JSON_BOOLEAN:
+      return visitor.visitBoolean(_data->content.asInteger != 0);
+
     default:
-      return static_cast<T>(_content.asFloat);
+      return visitor.visitNull();
   }
 }
 
-inline bool JsonVariant::variantIsBoolean() const {
-  using namespace Internals;
-  return _type == JSON_BOOLEAN;
+inline JsonVariantConst JsonVariantConst::operator[](size_t index) const {
+  return JsonArrayConst(variantAsArray(_data))[index];
 }
 
-inline bool JsonVariant::variantIsInteger() const {
-  using namespace Internals;
-
-  return _type == JSON_POSITIVE_INTEGER || _type == JSON_NEGATIVE_INTEGER;
-}
-
-inline bool JsonVariant::variantIsFloat() const {
-  using namespace Internals;
-
-  return _type == JSON_FLOAT || _type == JSON_POSITIVE_INTEGER ||
-         _type == JSON_NEGATIVE_INTEGER;
-}
-
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/JsonVariantOr.hpp

@@ -8,8 +8,7 @@
 #include "Polyfills/attributes.hpp"
 #include "Polyfills/type_traits.hpp"
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 template <typename TImpl>
 class JsonVariantOr {
@@ -47,5 +46,4 @@ class JsonVariantOr {
     return static_cast<const TImpl *>(this);
   }
 };
-}  // namespace Internals
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/JsonVariantSubscripts.hpp

@@ -9,10 +9,9 @@
 #include "Polyfills/type_traits.hpp"
 #include "Strings/StringTypes.hpp"
 
-namespace ArduinoJson {
+namespace ARDUINOJSON_NAMESPACE {
 class JsonArray;
 class JsonObject;
-namespace Internals {
 
 // Forward declarations.
 class JsonArraySubscript;
@@ -22,57 +21,31 @@ class JsonObjectSubscript;
 template <typename TImpl>
 class JsonVariantSubscripts {
  public:
-  // Mimics an array or an object.
-  // Returns the size of the array or object if the variant has that type.
-  // Returns 0 if the variant is neither an array nor an object
-  size_t size() const {
-    return impl()->template as<JsonArray>().size() +
-           impl()->template as<JsonObject>().size();
-  }
-
   // Mimics an array.
   // Returns the element at specified index if the variant is an array.
-  FORCE_INLINE const JsonArraySubscript operator[](size_t index) const;
-  FORCE_INLINE JsonArraySubscript operator[](size_t index);
+  FORCE_INLINE JsonArraySubscript operator[](size_t index) const;
 
   // Mimics an object.
   // Returns the value associated with the specified key if the variant is
   // an object.
   //
-  // const JsonObjectSubscript operator[](TKey) const;
-  // TKey = const std::string&, const String&
-  template <typename TString>
-  FORCE_INLINE
-      typename enable_if<IsString<TString>::value,
-                         const JsonObjectSubscript<const TString &> >::type
-      operator[](const TString &key) const;
-  //
-  // const JsonObjectSubscript operator[](TKey) const;
+  // JsonObjectSubscript operator[](TKey) const;
   // TKey = const std::string&, const String&
   template <typename TString>
   FORCE_INLINE typename enable_if<IsString<TString>::value,
                                   JsonObjectSubscript<const TString &> >::type
-  operator[](const TString &key);
+  operator[](const TString &key) const;
   //
-  // JsonObjectSubscript operator[](TKey);
+  // JsonObjectSubscript operator[](TKey) const;
   // TKey = const char*, const char[N], const FlashStringHelper*
   template <typename TString>
-  FORCE_INLINE typename enable_if<IsString<const TString *>::value,
-                                  JsonObjectSubscript<const TString *> >::type
-  operator[](const TString *key);
-  //
-  // JsonObjectSubscript operator[](TKey);
-  // TKey = const char*, const char[N], const FlashStringHelper*
-  template <typename TString>
-  FORCE_INLINE
-      typename enable_if<IsString<TString *>::value,
-                         const JsonObjectSubscript<const TString *> >::type
-      operator[](const TString *key) const;
+  FORCE_INLINE typename enable_if<IsString<TString *>::value,
+                                  JsonObjectSubscript<TString *> >::type
+  operator[](TString *key) const;
 
  private:
   const TImpl *impl() const {
     return static_cast<const TImpl *>(this);
   }
 };
-}  // namespace Internals
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Memory/Alignment.hpp

@@ -0,0 +1,28 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2018
+// MIT License
+
+#pragma once
+
+#include <stddef.h>  // size_t
+
+namespace ARDUINOJSON_NAMESPACE {
+
+inline bool isAligned(void *ptr) {
+  const size_t mask = sizeof(void *) - 1;
+  size_t addr = reinterpret_cast<size_t>(ptr);
+  return (addr & mask) == 0;
+}
+
+inline size_t addPadding(size_t bytes) {
+  const size_t mask = sizeof(void *) - 1;
+  return (bytes + mask) & ~mask;
+}
+
+template <size_t bytes>
+struct AddPadding {
+  static const size_t mask = sizeof(void *) - 1;
+  static const size_t value = (bytes + mask) & ~mask;
+};
+
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Memory/DynamicJsonBuffer.hpp

@@ -1,169 +0,0 @@
-// ArduinoJson - arduinojson.org
-// Copyright Benoit Blanchon 2014-2018
-// MIT License
-
-#pragma once
-
-#include "JsonBuffer.hpp"
-
-#include <stdlib.h>
-
-#if defined(__clang__)
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wnon-virtual-dtor"
-#elif defined(__GNUC__)
-#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
-#pragma GCC diagnostic push
-#endif
-#pragma GCC diagnostic ignored "-Wnon-virtual-dtor"
-#endif
-
-namespace ArduinoJson {
-namespace Internals {
-class DefaultAllocator {
- public:
-  void* allocate(size_t size) {
-    return malloc(size);
-  }
-  void deallocate(void* pointer) {
-    free(pointer);
-  }
-};
-
-template <typename TAllocator>
-class DynamicJsonBufferBase : public JsonBuffer {
-  struct Block;
-  struct EmptyBlock {
-    Block* next;
-    size_t capacity;
-    size_t size;
-  };
-  struct Block : EmptyBlock {
-    uint8_t data[1];
-  };
-
- public:
-  enum { EmptyBlockSize = sizeof(EmptyBlock) };
-
-  DynamicJsonBufferBase(size_t initialSize = 256)
-      : _head(NULL), _nextBlockCapacity(initialSize) {}
-
-  ~DynamicJsonBufferBase() {
-    clear();
-  }
-
-  // Gets the number of bytes occupied in the buffer
-  size_t size() const {
-    size_t total = 0;
-    for (const Block* b = _head; b; b = b->next) total += b->size;
-    return total;
-  }
-
-  // Allocates the specified amount of bytes in the buffer
-  virtual void* alloc(size_t bytes) {
-    alignNextAlloc();
-    return canAllocInHead(bytes) ? allocInHead(bytes) : allocInNewBlock(bytes);
-  }
-
-  // Resets the buffer.
-  // USE WITH CAUTION: this invalidates all previously allocated data
-  void clear() {
-    Block* currentBlock = _head;
-    while (currentBlock != NULL) {
-      _nextBlockCapacity = currentBlock->capacity;
-      Block* nextBlock = currentBlock->next;
-      _allocator.deallocate(currentBlock);
-      currentBlock = nextBlock;
-    }
-    _head = 0;
-  }
-
-  class String {
-   public:
-    String(DynamicJsonBufferBase* parent)
-        : _parent(parent), _start(NULL), _length(0) {}
-
-    void append(char c) {
-      if (_parent->canAllocInHead(1)) {
-        char* end = static_cast<char*>(_parent->allocInHead(1));
-        *end = c;
-        if (_length == 0) _start = end;
-      } else {
-        char* newStart =
-            static_cast<char*>(_parent->allocInNewBlock(_length + 1));
-        if (_start && newStart) memcpy(newStart, _start, _length);
-        if (newStart) newStart[_length] = c;
-        _start = newStart;
-      }
-      _length++;
-    }
-
-    const char* c_str() {
-      append(0);
-      return _start;
-    }
-
-   private:
-    DynamicJsonBufferBase* _parent;
-    char* _start;
-    size_t _length;
-  };
-
-  String startString() {
-    return String(this);
-  }
-
- private:
-  void alignNextAlloc() {
-    if (_head) _head->size = this->round_size_up(_head->size);
-  }
-
-  bool canAllocInHead(size_t bytes) const {
-    return _head != NULL && _head->size + bytes <= _head->capacity;
-  }
-
-  void* allocInHead(size_t bytes) {
-    void* p = _head->data + _head->size;
-    _head->size += bytes;
-    return p;
-  }
-
-  void* allocInNewBlock(size_t bytes) {
-    size_t capacity = _nextBlockCapacity;
-    if (bytes > capacity) capacity = bytes;
-    if (!addNewBlock(capacity)) return NULL;
-    _nextBlockCapacity *= 2;
-    return allocInHead(bytes);
-  }
-
-  bool addNewBlock(size_t capacity) {
-    size_t bytes = EmptyBlockSize + capacity;
-    Block* block = static_cast<Block*>(_allocator.allocate(bytes));
-    if (block == NULL) return false;
-    block->capacity = capacity;
-    block->size = 0;
-    block->next = _head;
-    _head = block;
-    return true;
-  }
-
-  TAllocator _allocator;
-  Block* _head;
-  size_t _nextBlockCapacity;
-};
-
-// Implements a JsonBuffer with dynamic memory allocation.
-// You are strongly encouraged to consider using StaticJsonBuffer which is much
-// more suitable for embedded systems.
-typedef Internals::DynamicJsonBufferBase<Internals::DefaultAllocator>
-    DynamicJsonBuffer;
-}  // namespace Internals
-
-#if defined(__clang__)
-#pragma clang diagnostic pop
-#elif defined(__GNUC__)
-#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
-#pragma GCC diagnostic pop
-#endif
-#endif
-}  // namespace ArduinoJson

src/ArduinoJson/Memory/DynamicMemoryPool.hpp

@@ -0,0 +1,187 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2018
+// MIT License
+
+#pragma once
+
+#include "../Strings/StringInMemoryPool.hpp"
+#include "Alignment.hpp"
+#include "MemoryPool.hpp"
+#include "StaticMemoryPool.hpp"
+
+#include <stdlib.h>  // malloc, free
+
+#if defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wnon-virtual-dtor"
+#elif defined(__GNUC__)
+#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
+#pragma GCC diagnostic push
+#endif
+#pragma GCC diagnostic ignored "-Wnon-virtual-dtor"
+#endif
+
+namespace ARDUINOJSON_NAMESPACE {
+class DefaultAllocator {
+ public:
+  void* allocate(size_t size) {
+    return malloc(size);
+  }
+  void deallocate(void* pointer) {
+    free(pointer);
+  }
+};
+
+template <typename TAllocator>
+class DynamicMemoryPoolBase : public MemoryPool {
+  class Block : public StaticMemoryPoolBase {
+   public:
+    Block(char* buf, size_t sz, Block* nxt)
+        : StaticMemoryPoolBase(buf, sz), next(nxt) {}
+    Block* next;
+  };
+
+ public:
+  enum { EmptyBlockSize = sizeof(Block) };
+
+  DynamicMemoryPoolBase(size_t initialSize = ARDUINOJSON_DEFAULT_POOL_SIZE)
+      : _head(NULL), _nextBlockCapacity(initialSize) {}
+
+  ~DynamicMemoryPoolBase() {
+    clear();
+  }
+
+  void reserve(size_t capacity) {
+    _nextBlockCapacity = capacity;
+  }
+
+  virtual size_t size() const {
+    size_t sum = 0;
+    for (Block* b = _head; b; b = b->next) {
+      sum += b->size();
+    }
+    return sum;
+  }
+
+  virtual VariantSlot* allocVariant() {
+    for (Block* b = _head; b; b = b->next) {
+      VariantSlot* s = b->allocVariant();
+      if (s) return s;
+    }
+
+    if (!addNewBlock(sizeof(VariantSlot))) return 0;
+
+    return _head->allocVariant();
+  }
+
+  virtual void freeVariant(VariantSlot* slot) {
+    for (Block* b = _head; b; b = b->next) {
+      if (b->owns(slot)) {
+        b->freeVariant(slot);
+        break;
+      }
+    }
+  }
+
+  virtual void freeString(StringSlot* slot) {
+    for (Block* b = _head; b; b = b->next) {
+      if (b->owns(slot)) {
+        b->freeString(slot);
+        break;
+      }
+    }
+  }
+
+  virtual StringSlot* allocFrozenString(size_t n) {
+    for (Block* b = _head; b; b = b->next) {
+      StringSlot* s = b->allocFrozenString(n);
+      if (s) return s;
+    }
+
+    if (!addNewBlock(sizeof(StringSlot) + n)) return 0;
+
+    return _head->allocFrozenString(n);
+  }
+
+  virtual StringSlot* allocExpandableString() {
+    for (Block* b = _head; b; b = b->next) {
+      StringSlot* s = b->allocExpandableString();
+      if (s) return s;
+    }
+
+    if (!addNewBlock(sizeof(StringSlot))) return 0;
+
+    return _head->allocExpandableString();
+  }
+
+  virtual StringSlot* expandString(StringSlot* oldSlot) {
+    if (!addNewBlock(sizeof(StringSlot) + oldSlot->size)) return 0;
+
+    StringSlot* newSlot = _head->allocExpandableString();
+
+    ARDUINOJSON_ASSERT(newSlot->size > oldSlot->size);
+    memcpy(newSlot->value, oldSlot->value, oldSlot->size);
+    freeString(oldSlot);
+
+    return newSlot;
+  }
+
+  virtual void freezeString(StringSlot* slot, size_t newSize) {
+    for (Block* b = _head; b; b = b->next) {
+      if (b->owns(slot)) {
+        b->freezeString(slot, newSize);
+      }
+    }
+  }
+
+  // Resets the memoryPool.
+  // USE WITH CAUTION: this invalidates all previously allocated data
+  void clear() {
+    Block* currentBlock = _head;
+    while (currentBlock != NULL) {
+      _nextBlockCapacity = currentBlock->capacity();
+      Block* nextBlock = currentBlock->next;
+      _allocator.deallocate(currentBlock);
+      currentBlock = nextBlock;
+    }
+    _head = 0;
+  }
+
+  size_t blockCount() const {
+    size_t sum = 0;
+    for (Block* b = _head; b; b = b->next) sum++;
+    return sum;
+  }
+
+ private:
+  bool addNewBlock(size_t minCapacity) {
+    size_t capacity = _nextBlockCapacity;
+    if (minCapacity > capacity) capacity = minCapacity;
+    capacity = addPadding(capacity);
+    size_t bytes = sizeof(Block) + capacity;
+    char* p = reinterpret_cast<char*>(_allocator.allocate(bytes));
+    if (!p) return false;
+    Block* block = new (p) Block(p + sizeof(Block), capacity, _head);
+    _nextBlockCapacity = capacity * 2;
+    _head = block;
+    return true;
+  }
+
+  TAllocator _allocator;
+  Block* _head;
+  size_t _nextBlockCapacity;
+};
+
+// Implements a MemoryPool with dynamic memory allocation.
+// You are strongly encouraged to consider using StaticMemoryPool which is much
+// more suitable for embedded systems.
+typedef DynamicMemoryPoolBase<DefaultAllocator> DynamicMemoryPool;
+}  // namespace ARDUINOJSON_NAMESPACE
+
+#if defined(__clang__)
+#pragma clang diagnostic pop
+#elif defined(__GNUC__)
+#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
+#pragma GCC diagnostic pop
+#endif
+#endif

src/ArduinoJson/Memory/JsonBuffer.hpp

@@ -1,42 +0,0 @@
-// ArduinoJson - arduinojson.org
-// Copyright Benoit Blanchon 2014-2018
-// MIT License
-
-#pragma once
-
-#include <stddef.h>  // for size_t
-#include <stdint.h>  // for uint8_t
-#include <string.h>
-
-#include "../Configuration.hpp"
-#include "../Polyfills/attributes.hpp"
-
-namespace ArduinoJson {
-namespace Internals {
-// Handle the memory management (done in derived classes) and calls the parser.
-// This abstract class is implemented by StaticJsonBuffer which implements a
-// fixed memory allocation.
-class JsonBuffer {
- public:
-  // Allocates n bytes in the JsonBuffer.
-  // Return a pointer to the allocated memory or NULL if allocation fails.
-  virtual void *alloc(size_t size) = 0;
-
- protected:
-  // CAUTION: NO VIRTUAL DESTRUCTOR!
-  // If we add a virtual constructor the Arduino compiler will add malloc()
-  // and free() to the binary, adding 706 useless bytes.
-  ~JsonBuffer() {}
-
-  // Preserve aligment if necessary
-  static FORCE_INLINE size_t round_size_up(size_t bytes) {
-#if ARDUINOJSON_ENABLE_ALIGNMENT
-    const size_t x = sizeof(void *) - 1;
-    return (bytes + x) & ~x;
-#else
-    return bytes;
-#endif
-  }
-};
-}  // namespace Internals
-}  // namespace ArduinoJson

src/ArduinoJson/Memory/JsonBufferAllocated.hpp

@@ -1,22 +0,0 @@
-// ArduinoJson - arduinojson.org
-// Copyright Benoit Blanchon 2014-2018
-// MIT License
-
-#pragma once
-
-#include "JsonBuffer.hpp"
-
-namespace ArduinoJson {
-namespace Internals {
-
-class JsonBufferAllocated {
- public:
-  void *operator new(size_t n, JsonBuffer *jsonBuffer) throw() {
-    if (!jsonBuffer) return NULL;
-    return jsonBuffer->alloc(n);
-  }
-
-  void operator delete(void *, JsonBuffer *)throw();
-};
-}  // namespace Internals
-}  // namespace ArduinoJson

src/ArduinoJson/Memory/MemoryPool.hpp

@@ -0,0 +1,34 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2018
+// MIT License
+
+#pragma once
+
+#include <stddef.h>  // for size_t
+
+#include "../Polyfills/attributes.hpp"
+#include "StringSlot.hpp"
+#include "VariantSlot.hpp"
+
+namespace ARDUINOJSON_NAMESPACE {
+
+class MemoryPool {
+ public:
+  virtual StringSlot *allocExpandableString() = 0;
+  virtual StringSlot *allocFrozenString(size_t) = 0;
+  virtual StringSlot *expandString(StringSlot *) = 0;
+  virtual void freezeString(StringSlot *, size_t) = 0;
+  virtual void freeString(StringSlot *) = 0;
+
+  virtual VariantSlot *allocVariant() = 0;
+  virtual void freeVariant(VariantSlot *) = 0;
+
+  virtual size_t size() const = 0;
+
+ protected:
+  // CAUTION: NO VIRTUAL DESTRUCTOR!
+  // If we add a virtual constructor the Arduino compiler will add malloc()
+  // and free() to the binary, adding 706 useless bytes.
+  ~MemoryPool() {}
+};
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Memory/SlotList.hpp

@@ -0,0 +1,67 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2018
+// MIT License
+
+#pragma once
+
+#include <stddef.h>  // for size_t
+
+namespace ARDUINOJSON_NAMESPACE {
+
+template <typename TSlot>
+class SlotList {
+ public:
+  SlotList() : _head(0) {}
+
+  TSlot *pop() {
+    TSlot *slot = _head;
+    if (slot) _head = slot->next;
+    return slot;
+  }
+
+  void push(TSlot *slot) {
+    slot->next = _head;
+    _head = slot;
+  }
+
+  bool remove(const TSlot *slot) {
+    if (_head == slot) {
+      _head = slot->next;
+      return true;
+    }
+
+    for (TSlot *s = _head; s; s = s->next) {
+      if (s->next == slot) {
+        s->next = slot->next;
+        return true;
+      }
+    }
+
+    return false;
+  }
+
+  bool remove(const void *slot) {
+    return remove(reinterpret_cast<const TSlot *>(slot));
+  }
+
+  template <typename Functor>
+  void forEach(const Functor &f) {
+    for (TSlot *s = _head; s; s = s->next) {
+      f(s);
+    }
+  }
+
+  size_t size() const {
+    size_t sum = 0;
+    for (TSlot *s = _head; s; s = s->next) sum += sizeof(TSlot);
+    return sum;
+  }
+
+  void clear() {
+    _head = 0;
+  }
+
+ private:
+  TSlot *_head;
+};
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Memory/StaticJsonBuffer.hpp

@@ -1,129 +0,0 @@
-// ArduinoJson - arduinojson.org
-// Copyright Benoit Blanchon 2014-2018
-// MIT License
-
-#pragma once
-
-#include "../Polyfills/mpl/max.hpp"
-#include "JsonBuffer.hpp"
-
-namespace ArduinoJson {
-namespace Internals {
-
-class StaticJsonBufferBase : public JsonBuffer {
- public:
-  class String {
-   public:
-    String(StaticJsonBufferBase* parent) : _parent(parent) {
-      _start = parent->_buffer + parent->_size;
-    }
-
-    void append(char c) {
-      if (_parent->canAlloc(1)) {
-        char* last = static_cast<char*>(_parent->doAlloc(1));
-        *last = c;
-      }
-    }
-
-    const char* c_str() const {
-      if (_parent->canAlloc(1)) {
-        char* last = static_cast<char*>(_parent->doAlloc(1));
-        *last = '\0';
-        return _start;
-      } else {
-        return NULL;
-      }
-    }
-
-   private:
-    StaticJsonBufferBase* _parent;
-    char* _start;
-  };
-
-  StaticJsonBufferBase(char* buffer, size_t capa)
-      : _buffer(buffer), _capacity(capa), _size(0) {}
-
-  // Gets the capacity of the buffer in bytes
-  size_t capacity() const {
-    return _capacity;
-  }
-
-  // Gets the current usage of the buffer in bytes
-  size_t size() const {
-    return _size;
-  }
-
-  // Allocates the specified amount of bytes in the buffer
-  virtual void* alloc(size_t bytes) {
-    alignNextAlloc();
-    if (!canAlloc(bytes)) return NULL;
-    return doAlloc(bytes);
-  }
-
-  // Resets the buffer.
-  // USE WITH CAUTION: this invalidates all previously allocated data
-  void clear() {
-    _size = 0;
-  }
-
-  String startString() {
-    return String(this);
-  }
-
- protected:
-  ~StaticJsonBufferBase() {}
-
- private:
-  void alignNextAlloc() {
-    _size = round_size_up(_size);
-  }
-
-  bool canAlloc(size_t bytes) const {
-    return _size + bytes <= _capacity;
-  }
-
-  void* doAlloc(size_t bytes) {
-    void* p = &_buffer[_size];
-    _size += bytes;
-    return p;
-  }
-
-  char* _buffer;
-  size_t _capacity;
-  size_t _size;
-};
-
-#if defined(__clang__)
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wnon-virtual-dtor"
-#elif defined(__GNUC__)
-#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
-#pragma GCC diagnostic push
-#endif
-#pragma GCC diagnostic ignored "-Wnon-virtual-dtor"
-#endif
-
-// Implements a JsonBuffer with fixed memory allocation.
-// The template paramenter CAPACITY specifies the capacity of the buffer in
-// bytes.
-template <size_t CAPACITY>
-class StaticJsonBuffer : public Internals::StaticJsonBufferBase {
-  static const size_t ACTUAL_CAPACITY = Internals::Max<1, CAPACITY>::value;
-
- public:
-  explicit StaticJsonBuffer()
-      : Internals::StaticJsonBufferBase(_buffer, ACTUAL_CAPACITY) {}
-
- private:
-  char _buffer[ACTUAL_CAPACITY];
-};
-}  // namespace Internals
-}  // namespace ArduinoJson
-
-#if defined(__clang__)
-#pragma clang diagnostic pop
-#elif defined(__GNUC__)
-#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
-#pragma GCC diagnostic pop
-#endif
-#endif

src/ArduinoJson/Memory/StaticMemoryPool.hpp

@@ -0,0 +1,236 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2018
+// MIT License
+
+#pragma once
+
+#include "../Polyfills/assert.hpp"
+#include "../Polyfills/mpl/max.hpp"
+#include "../Strings/StringInMemoryPool.hpp"
+#include "Alignment.hpp"
+#include "MemoryPool.hpp"
+#include "SlotList.hpp"
+
+namespace ARDUINOJSON_NAMESPACE {
+
+// _begin                                _end
+// v                                        v
+// +-------------+--------------+-----------+
+// | strings...  |   (free)     |  ...slots |
+// +-------------+--------------+-----------+
+//               ^              ^
+//             _left          _right
+
+class StaticMemoryPoolBase : public MemoryPool {
+  class UpdateStringSlotAddress {
+   public:
+    UpdateStringSlotAddress(const char* address, size_t offset)
+        : _address(address), _offset(offset) {}
+
+    void operator()(StringSlot* slot) const {
+      ARDUINOJSON_ASSERT(slot != NULL);
+      if (slot->value > _address) slot->value -= _offset;
+    }
+
+   private:
+    const char* _address;
+    size_t _offset;
+  };
+
+ public:
+  // Gets the capacity of the memoryPool in bytes
+  size_t capacity() const {
+    return size_t(_end - _begin);
+  }
+
+  virtual size_t size() const {
+    return allocated_bytes() - _freeVariants.size() - _freeStrings.size();
+  }
+
+  virtual VariantSlot* allocVariant() {
+    VariantSlot* s = _freeVariants.pop();
+    if (s) return s;
+    return s ? s : allocRight<VariantSlot>();
+  }
+
+  virtual void freeVariant(VariantSlot* slot) {
+    freeVariantSlot(slot);
+    compactRightSide();
+  }
+
+  virtual void freeString(StringSlot* slot) {
+    freeStringSlot(slot);
+    compactLeftSide(slot->value, slot->size);
+    compactRightSide();
+  }
+
+  virtual StringSlot* allocFrozenString(size_t n) {
+    StringSlot* s = allocStringSlot();
+    if (!s) return 0;
+    if (!canAlloc(n)) return 0;
+
+    s->value = _left;
+    s->size = n;
+    _left += n;
+    _usedString.push(s);
+    checkInvariants();
+
+    return s;
+  }
+
+  virtual StringSlot* allocExpandableString() {
+    StringSlot* s = allocStringSlot();
+    if (!s) return 0;
+
+    s->value = _left;
+    s->size = size_t(_right - _left);
+    _usedString.push(s);
+    _left = _right;
+
+    checkInvariants();
+    return s;
+  }
+
+  virtual StringSlot* expandString(StringSlot*) {
+    return 0;
+  }
+
+  virtual void freezeString(StringSlot* slot, size_t newSize) {
+    _left -= (slot->size - newSize);
+    slot->size = newSize;
+    checkInvariants();
+  }
+
+  void clear() {
+    _left = _begin;
+    _right = _end;
+    _freeVariants.clear();
+    _freeStrings.clear();
+    _usedString.clear();
+  }
+
+  bool canAlloc(size_t bytes) const {
+    return _left + bytes <= _right;
+  }
+
+  bool owns(void* p) const {
+    return _begin <= p && p < _end;
+  }
+
+  template <typename T>
+  T* allocRight() {
+    return reinterpret_cast<T*>(allocRight(sizeof(T)));
+  }
+
+  char* allocRight(size_t bytes) {
+    if (!canAlloc(bytes)) return 0;
+    _right -= bytes;
+    return _right;
+  }
+
+  // Workaround for missing placement new
+  void* operator new(size_t, void* p) {
+    return p;
+  }
+
+ protected:
+  StaticMemoryPoolBase(char* buffer, size_t capa)
+      : _begin(buffer),
+        _left(buffer),
+        _right(buffer + capa),
+        _end(buffer + capa) {}
+
+  ~StaticMemoryPoolBase() {}
+
+  // Gets the current usage of the memoryPool in bytes
+  size_t allocated_bytes() const {
+    return size_t(_left - _begin + _end - _right);
+  }
+
+ private:
+  StringSlot* allocStringSlot() {
+    StringSlot* s = _freeStrings.pop();
+    if (s) return s;
+    return allocRight<StringSlot>();
+  }
+
+  void freeVariantSlot(VariantSlot* slot) {
+    _freeVariants.push(slot);
+  }
+
+  void freeStringSlot(StringSlot* slot) {
+    _usedString.remove(slot);
+    _freeStrings.push(slot);
+  }
+
+  void compactLeftSide(char* holeAddress, size_t holeSize) {
+    ARDUINOJSON_ASSERT(holeAddress >= _begin);
+    ARDUINOJSON_ASSERT(holeAddress + holeSize <= _left);
+    char* holeEnd = holeAddress + holeSize;
+    memmove(holeAddress,               // where the hole begun
+            holeEnd,                   // where the hole ended
+            size_t(_left - holeEnd));  // everything after the hole
+    _left -= holeSize;
+    _usedString.forEach(UpdateStringSlotAddress(holeAddress, holeSize));
+    checkInvariants();
+  }
+
+  void compactRightSide() {
+  loop:
+    if (_freeStrings.remove(_right)) {
+      _right += sizeof(StringSlot);
+      goto loop;
+    }
+    if (_freeVariants.remove(_right)) {
+      _right += sizeof(VariantSlot);
+      goto loop;
+    }
+    checkInvariants();
+  }
+
+  void checkInvariants() {
+    ARDUINOJSON_ASSERT(_begin <= _left);
+    ARDUINOJSON_ASSERT(_left <= _right);
+    ARDUINOJSON_ASSERT(_right <= _end);
+  }
+
+  char *_begin, *_left, *_right, *_end;
+  SlotList<VariantSlot> _freeVariants;
+  SlotList<StringSlot> _freeStrings;
+  SlotList<StringSlot> _usedString;
+};  // namespace ARDUINOJSON_NAMESPACE
+
+#if defined(__clang__)
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wnon-virtual-dtor"
+#elif defined(__GNUC__)
+#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
+#pragma GCC diagnostic push
+#endif
+#pragma GCC diagnostic ignored "-Wnon-virtual-dtor"
+#endif
+
+// Implements a MemoryPool with fixed memory allocation.
+// The template paramenter CAPACITY specifies the capacity of the memoryPool in
+// bytes.
+template <size_t CAPACITY>
+class StaticMemoryPool : public StaticMemoryPoolBase {
+  static const size_t ACTUAL_CAPACITY =
+      AddPadding<Max<1, CAPACITY>::value>::value;
+
+ public:
+  explicit StaticMemoryPool()
+      : StaticMemoryPoolBase(_buffer, ACTUAL_CAPACITY) {}
+
+ private:
+  char _buffer[ACTUAL_CAPACITY];
+};
+}  // namespace ARDUINOJSON_NAMESPACE
+
+#if defined(__clang__)
+#pragma clang diagnostic pop
+#elif defined(__GNUC__)
+#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 6)
+#pragma GCC diagnostic pop
+#endif
+#endif

src/ArduinoJson/Memory/StringBuilder.hpp

@@ -0,0 +1,53 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2018
+// MIT License
+
+#pragma once
+
+#include "../Strings/StringInMemoryPool.hpp"
+#include "MemoryPool.hpp"
+
+namespace ARDUINOJSON_NAMESPACE {
+
+class StringBuilder {
+ public:
+  typedef StringInMemoryPool StringType;
+
+  explicit StringBuilder(MemoryPool* parent) : _parent(parent), _size(0) {
+    _slot = _parent->allocExpandableString();
+  }
+
+  void append(const char* s) {
+    while (*s) append(*s++);
+  }
+
+  void append(const char* s, size_t n) {
+    while (n-- > 0) append(*s++);
+  }
+
+  void append(char c) {
+    if (!_slot) return;
+
+    if (_size >= _slot->size) {
+      _slot = _parent->expandString(_slot);
+      if (!_slot) return;
+    }
+
+    _slot->value[_size++] = c;
+  }
+
+  StringType complete() {
+    append('\0');
+    if (_slot) {
+      _parent->freezeString(_slot, _size);
+    }
+    return _slot;
+  }
+
+ private:
+  MemoryPool* _parent;
+  size_t _size;
+  StringSlot* _slot;
+};
+
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Memory/StringSlot.hpp

@@ -0,0 +1,20 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2018
+// MIT License
+
+#pragma once
+
+#include <stddef.h>  // for size_t
+#include "../Configuration.hpp"
+
+#define JSON_STRING_SIZE(SIZE) \
+  (sizeof(ARDUINOJSON_NAMESPACE::StringSlot) + (SIZE))
+
+namespace ARDUINOJSON_NAMESPACE {
+
+struct StringSlot {
+  char *value;
+  size_t size;
+  struct StringSlot *next;
+};
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Memory/VariantSlot.hpp

@@ -0,0 +1,21 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2018
+// MIT License
+
+#pragma once
+
+#include "../Data/JsonVariantData.hpp"
+
+namespace ARDUINOJSON_NAMESPACE {
+
+struct VariantSlot {
+  JsonVariantData value;
+  struct VariantSlot* next;
+  struct VariantSlot* prev;
+  union {
+    const char* linkedKey;
+    StringSlot* ownedKey;
+  };
+};
+
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/MsgPack/MsgPackDeserializer.hpp

@@ -6,35 +6,38 @@
 
 #include "../Deserialization/deserialize.hpp"
 #include "../JsonVariant.hpp"
-#include "../Memory/JsonBuffer.hpp"
+#include "../Memory/MemoryPool.hpp"
 #include "../Polyfills/type_traits.hpp"
 #include "./endianess.hpp"
 #include "./ieee754.hpp"
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 template <typename TReader, typename TStringStorage>
 class MsgPackDeserializer {
+  typedef typename remove_reference<TStringStorage>::type::StringBuilder
+      StringBuilder;
+  typedef typename StringBuilder::StringType StringType;
+
  public:
-  MsgPackDeserializer(JsonBuffer *buffer, TReader reader,
+  MsgPackDeserializer(MemoryPool &memoryPool, TReader reader,
                       TStringStorage stringStorage, uint8_t nestingLimit)
-      : _buffer(buffer),
+      : _memoryPool(&memoryPool),
         _reader(reader),
         _stringStorage(stringStorage),
         _nestingLimit(nestingLimit) {}
 
-  DeserializationError parse(JsonVariant &variant) {
+  DeserializationError parse(JsonVariant variant) {
     uint8_t code;
     if (!readByte(code)) return DeserializationError::IncompleteInput;
 
     if ((code & 0x80) == 0) {
-      variant = code;
+      variant.set(code);
       return DeserializationError::Ok;
     }
 
     if ((code & 0xe0) == 0xe0) {
-      variant = static_cast<int8_t>(code);
+      variant.set(static_cast<int8_t>(code));
       return DeserializationError::Ok;
     }
 
@@ -48,15 +51,15 @@ class MsgPackDeserializer {
 
     switch (code) {
       case 0xc0:
-        variant = static_cast<char *>(0);
+        // already null
         return DeserializationError::Ok;
 
       case 0xc2:
-        variant = false;
+        variant.set(false);
         return DeserializationError::Ok;
 
       case 0xc3:
-        variant = true;
+        variant.set(true);
         return DeserializationError::Ok;
 
       case 0xcc:
@@ -69,7 +72,7 @@ class MsgPackDeserializer {
         return readInteger<uint32_t>(variant);
 
       case 0xcf:
-#if ARDUINOJSON_USE_LONG_LONG || ARDUINOJSON_USE_INT64
+#if ARDUINOJSON_USE_LONG_LONG
         return readInteger<uint64_t>(variant);
 #else
         readInteger<uint32_t>();
@@ -86,7 +89,7 @@ class MsgPackDeserializer {
         return readInteger<int32_t>(variant);
 
       case 0xd3:
-#if ARDUINOJSON_USE_LONG_LONG || ARDUINOJSON_USE_INT64
+#if ARDUINOJSON_USE_LONG_LONG
         return readInteger<int64_t>(variant);
 #else
         if (!skip(4)) return DeserializationError::IncompleteInput;
@@ -171,78 +174,89 @@ class MsgPackDeserializer {
   }
 
   template <typename T>
-  DeserializationError readInteger(JsonVariant &variant) {
+  DeserializationError readInteger(JsonVariant variant) {
     T value;
     if (!readInteger(value)) return DeserializationError::IncompleteInput;
-    variant = value;
+    variant.set(value);
     return DeserializationError::Ok;
   }
 
   template <typename T>
   typename enable_if<sizeof(T) == 4, DeserializationError>::type readFloat(
-      JsonVariant &variant) {
+      JsonVariant variant) {
     T value;
     if (!readBytes(value)) return DeserializationError::IncompleteInput;
     fixEndianess(value);
-    variant = value;
+    variant.set(value);
     return DeserializationError::Ok;
   }
 
   template <typename T>
   typename enable_if<sizeof(T) == 8, DeserializationError>::type readDouble(
-      JsonVariant &variant) {
+      JsonVariant variant) {
     T value;
     if (!readBytes(value)) return DeserializationError::IncompleteInput;
     fixEndianess(value);
-    variant = value;
+    variant.set(value);
     return DeserializationError::Ok;
   }
 
   template <typename T>
   typename enable_if<sizeof(T) == 4, DeserializationError>::type readDouble(
-      JsonVariant &variant) {
+      JsonVariant variant) {
     uint8_t i[8];  // input is 8 bytes
     T value;       // output is 4 bytes
     uint8_t *o = reinterpret_cast<uint8_t *>(&value);
     if (!readBytes(i, 8)) return DeserializationError::IncompleteInput;
     doubleToFloat(i, o);
     fixEndianess(value);
-    variant = value;
+    variant.set(value);
     return DeserializationError::Ok;
   }
 
   template <typename T>
-  DeserializationError readString(JsonVariant &variant) {
+  DeserializationError readString(JsonVariant variant) {
     T size;
     if (!readInteger(size)) return DeserializationError::IncompleteInput;
     return readString(variant, size);
   }
 
-  DeserializationError readString(JsonVariant &variant, size_t n) {
-    typename remove_reference<TStringStorage>::type::String str =
-        _stringStorage.startString();
+  template <typename T>
+  DeserializationError readString(StringType &str) {
+    T size;
+    if (!readInteger(size)) return DeserializationError::IncompleteInput;
+    return readString(str, size);
+  }
+
+  DeserializationError readString(JsonVariant variant, size_t n) {
+    StringType s;
+    DeserializationError err = readString(s, n);
+    if (!err) variant.set(s);
+    return err;
+  }
+
+  DeserializationError readString(StringType &s, size_t n) {
+    StringBuilder builder = _stringStorage.startString();
     for (; n; --n) {
       uint8_t c;
       if (!readBytes(c)) return DeserializationError::IncompleteInput;
-      str.append(static_cast<char>(c));
+      builder.append(static_cast<char>(c));
     }
-    const char *s = str.c_str();
-    if (s == NULL) return DeserializationError::NoMemory;
-    variant = s;
+    s = builder.complete();
+    if (s.isNull()) return DeserializationError::NoMemory;
     return DeserializationError::Ok;
   }
 
   template <typename TSize>
-  DeserializationError readArray(JsonVariant &variant) {
+  DeserializationError readArray(JsonVariant variant) {
     TSize size;
     if (!readInteger(size)) return DeserializationError::IncompleteInput;
     return readArray(variant, size);
   }
 
-  DeserializationError readArray(JsonVariant &variant, size_t n) {
-    JsonArray array(_buffer);
+  DeserializationError readArray(JsonVariant variant, size_t n) {
+    JsonArray array = variant.to<JsonArray>();
     if (array.isNull()) return DeserializationError::NoMemory;
-    variant = array;
     return readArray(array, n);
   }
 
@@ -250,26 +264,27 @@ class MsgPackDeserializer {
     if (_nestingLimit == 0) return DeserializationError::TooDeep;
     --_nestingLimit;
     for (; n; --n) {
-      JsonVariant variant;
-      DeserializationError err = parse(variant);
+      JsonVariant value = array.add();
+      if (value.isInvalid()) return DeserializationError::NoMemory;
+
+      DeserializationError err = parse(value);
       if (err) return err;
-      if (!array.add(variant)) return DeserializationError::NoMemory;
     }
     ++_nestingLimit;
     return DeserializationError::Ok;
   }
 
   template <typename TSize>
-  DeserializationError readObject(JsonVariant &variant) {
+  DeserializationError readObject(JsonVariant variant) {
     TSize size;
     if (!readInteger(size)) return DeserializationError::IncompleteInput;
     return readObject(variant, size);
   }
 
-  DeserializationError readObject(JsonVariant &variant, size_t n) {
-    JsonObject object(_buffer);
+  DeserializationError readObject(JsonVariant variant, size_t n) {
+    JsonObject object = variant.to<JsonObject>();
     if (object.isNull()) return DeserializationError::NoMemory;
-    variant = object;
+
     return readObject(object, n);
   }
 
@@ -277,49 +292,65 @@ class MsgPackDeserializer {
     if (_nestingLimit == 0) return DeserializationError::TooDeep;
     --_nestingLimit;
     for (; n; --n) {
-      DeserializationError err;
-      JsonVariant variant;
-      err = parse(variant);
+      StringType key;
+      DeserializationError err = parseKey(key);
       if (err) return err;
-      const char *key = variant.as<char *>();
-      if (!key) return DeserializationError::NotSupported;
-      err = parse(variant);
+
+      JsonVariant value = object.set(key);
+      if (value.isInvalid()) return DeserializationError::NoMemory;
+
+      err = parse(value);
       if (err) return err;
-      if (!object.set(key, variant)) return DeserializationError::NoMemory;
     }
     ++_nestingLimit;
     return DeserializationError::Ok;
   }
 
-  JsonBuffer *_buffer;
+  DeserializationError parseKey(StringType &key) {
+    uint8_t code;
+    if (!readByte(code)) return DeserializationError::IncompleteInput;
+
+    if ((code & 0xe0) == 0xa0) return readString(key, code & 0x1f);
+
+    switch (code) {
+      case 0xd9:
+        return readString<uint8_t>(key);
+
+      case 0xda:
+        return readString<uint16_t>(key);
+
+      case 0xdb:
+        return readString<uint32_t>(key);
+
+      default:
+        return DeserializationError::NotSupported;
+    }
+  }
+
+  MemoryPool *_memoryPool;
   TReader _reader;
   TStringStorage _stringStorage;
   uint8_t _nestingLimit;
 };
-}  // namespace Internals
 
 template <typename TDocument, typename TInput>
 DeserializationError deserializeMsgPack(TDocument &doc, const TInput &input) {
-  using namespace Internals;
   return deserialize<MsgPackDeserializer>(doc, input);
 }
 
 template <typename TDocument, typename TInput>
 DeserializationError deserializeMsgPack(TDocument &doc, TInput *input) {
-  using namespace Internals;
   return deserialize<MsgPackDeserializer>(doc, input);
 }
 
 template <typename TDocument, typename TInput>
 DeserializationError deserializeMsgPack(TDocument &doc, TInput *input,
                                         size_t inputSize) {
-  using namespace Internals;
   return deserialize<MsgPackDeserializer>(doc, input, inputSize);
 }
 
 template <typename TDocument, typename TInput>
 DeserializationError deserializeMsgPack(TDocument &doc, TInput &input) {
-  using namespace Internals;
   return deserialize<MsgPackDeserializer>(doc, input);
 }
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/MsgPack/MsgPackSerializer.hpp

@@ -10,8 +10,7 @@
 #include "../Serialization/serialize.hpp"
 #include "./endianess.hpp"
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 template <typename TWriter>
 class MsgPackSerializer {
@@ -19,13 +18,13 @@ class MsgPackSerializer {
   MsgPackSerializer(TWriter& writer) : _writer(&writer), _bytesWritten(0) {}
 
   template <typename T>
-  typename enable_if<sizeof(T) == 4>::type acceptFloat(T value32) {
+  typename enable_if<sizeof(T) == 4>::type visitFloat(T value32) {
     writeByte(0xCA);
     writeInteger(value32);
   }
 
   template <typename T>
-  typename enable_if<sizeof(T) == 8>::type acceptFloat(T value64) {
+  typename enable_if<sizeof(T) == 8>::type visitFloat(T value64) {
     float value32 = float(value64);
     if (value32 == value64) {
       writeByte(0xCA);
@@ -36,7 +35,7 @@ class MsgPackSerializer {
     }
   }
 
-  void acceptArray(const JsonArray& array) {
+  void visitArray(JsonArrayConst array) {
     size_t n = array.size();
     if (n < 0x10) {
       writeByte(uint8_t(0x90 + array.size()));
@@ -47,13 +46,12 @@ class MsgPackSerializer {
       writeByte(0xDD);
       writeInteger(uint32_t(n));
     }
-    for (JsonArray::const_iterator it = array.begin(); it != array.end();
-         ++it) {
-      it->visit(*this);
+    for (JsonArrayConst::iterator it = array.begin(); it != array.end(); ++it) {
+      it->accept(*this);
     }
   }
 
-  void acceptObject(const JsonObject& object) {
+  void visitObject(JsonObjectConst object) {
     size_t n = object.size();
     if (n < 0x10) {
       writeByte(uint8_t(0x80 + n));
@@ -64,14 +62,14 @@ class MsgPackSerializer {
       writeByte(0xDF);
       writeInteger(uint32_t(n));
     }
-    for (JsonObject::const_iterator it = object.begin(); it != object.end();
+    for (JsonObjectConst::iterator it = object.begin(); it != object.end();
          ++it) {
-      acceptString(it->key);
-      it->value.visit(*this);
+      visitString(it->key());
+      it->value().accept(*this);
     }
   }
 
-  void acceptString(const char* value) {
+  void visitString(const char* value) {
     if (!value) return writeByte(0xC0);  // nil
 
     size_t n = strlen(value);
@@ -91,11 +89,11 @@ class MsgPackSerializer {
     writeBytes(reinterpret_cast<const uint8_t*>(value), n);
   }
 
-  void acceptRawJson(const char* data, size_t size) {
+  void visitRawJson(const char* data, size_t size) {
     writeBytes(reinterpret_cast<const uint8_t*>(data), size);
   }
 
-  void acceptNegativeInteger(JsonUInt value) {
+  void visitNegativeInteger(JsonUInt value) {
     JsonUInt negated = JsonUInt(~value + 1);
     if (value <= 0x20) {
       writeInteger(int8_t(negated));
@@ -109,7 +107,7 @@ class MsgPackSerializer {
       writeByte(0xD2);
       writeInteger(int32_t(negated));
     }
-#if ARDUINOJSON_USE_LONG_LONG || ARDUINOJSON_USE_INT64
+#if ARDUINOJSON_USE_LONG_LONG
     else {
       writeByte(0xD3);
       writeInteger(int64_t(negated));
@@ -117,7 +115,7 @@ class MsgPackSerializer {
 #endif
   }
 
-  void acceptPositiveInteger(JsonUInt value) {
+  void visitPositiveInteger(JsonUInt value) {
     if (value <= 0x7F) {
       writeInteger(uint8_t(value));
     } else if (value <= 0xFF) {
@@ -130,7 +128,7 @@ class MsgPackSerializer {
       writeByte(0xCE);
       writeInteger(uint32_t(value));
     }
-#if ARDUINOJSON_USE_LONG_LONG || ARDUINOJSON_USE_INT64
+#if ARDUINOJSON_USE_LONG_LONG
     else {
       writeByte(0xCF);
       writeInteger(uint64_t(value));
@@ -138,11 +136,11 @@ class MsgPackSerializer {
 #endif
   }
 
-  void acceptBoolean(bool value) {
+  void visitBoolean(bool value) {
     writeByte(value ? 0xC3 : 0xC2);
   }
 
-  void acceptNull() {
+  void visitNull() {
     writeByte(0xC0);
   }
 
@@ -168,25 +166,21 @@ class MsgPackSerializer {
   TWriter* _writer;
   size_t _bytesWritten;
 };
-}  // namespace Internals
 
 template <typename TSource, typename TDestination>
 inline size_t serializeMsgPack(const TSource& source, TDestination& output) {
-  using namespace Internals;
   return serialize<MsgPackSerializer>(source, output);
 }
 
 template <typename TSource, typename TDestination>
 inline size_t serializeMsgPack(const TSource& source, TDestination* output,
                                size_t size) {
-  using namespace Internals;
   return serialize<MsgPackSerializer>(source, output, size);
 }
 
 template <typename TSource>
 inline size_t measureMsgPack(const TSource& source) {
-  using namespace Internals;
   return measure<MsgPackSerializer>(source);
 }
 
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/MsgPack/endianess.hpp

@@ -7,8 +7,7 @@
 #include "../Polyfills/type_traits.hpp"
 #include "../Polyfills/utility.hpp"
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 inline void fixEndianess(uint8_t* p, integral_constant<size_t, 8>) {
   swap(p[0], p[7]);
@@ -36,5 +35,4 @@ inline void fixEndianess(T& value) {
 #endif
 }
 
-}  // namespace Internals
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/MsgPack/ieee754.hpp

@@ -4,8 +4,7 @@
 
 #pragma once
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 inline void doubleToFloat(const uint8_t d[8], uint8_t f[4]) {
   f[0] = uint8_t((d[0] & 0xC0) | (d[0] << 3 & 0x3f) | (d[1] >> 5));
@@ -14,5 +13,4 @@ inline void doubleToFloat(const uint8_t d[8], uint8_t f[4]) {
   f[3] = uint8_t((d[3] << 3) | (d[4] >> 5));
 }
 
-}  // namespace Internals
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Namespace.hpp

@@ -0,0 +1,22 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2018
+// MIT License
+
+#pragma once
+
+#include "version.hpp"
+
+#include "Configuration.hpp"
+
+#define ARDUINOJSON_DO_CONCAT(A, B) A##B
+#define ARDUINOJSON_CONCAT2(A, B) ARDUINOJSON_DO_CONCAT(A, B)
+#define ARDUINOJSON_CONCAT4(A, B, C, D) \
+  ARDUINOJSON_CONCAT2(ARDUINOJSON_CONCAT2(A, B), ARDUINOJSON_CONCAT2(C, D))
+#define ARDUINOJSON_CONCAT8(A, B, C, D, E, F, G, H)    \
+  ARDUINOJSON_CONCAT2(ARDUINOJSON_CONCAT4(A, B, C, D), \
+                      ARDUINOJSON_CONCAT4(E, F, G, H))
+
+#define ARDUINOJSON_NAMESPACE                                                  \
+  ARDUINOJSON_CONCAT8(ArduinoJson, ARDUINOJSON_VERSION_MAJOR,                  \
+                      ARDUINOJSON_VERSION_MINOR, ARDUINOJSON_VERSION_REVISION, \
+                      _, ARDUINOJSON_USE_LONG_LONG, _, ARDUINOJSON_USE_DOUBLE)

src/ArduinoJson/Numbers/FloatParts.hpp

@@ -8,8 +8,7 @@
 #include "../Polyfills/math.hpp"
 #include "./FloatTraits.hpp"
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 template <typename TFloat>
 struct FloatParts {
@@ -85,5 +84,4 @@ struct FloatParts {
     return powersOf10;
   }
 };
-}  // namespace Internals
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Numbers/FloatTraits.hpp

@@ -4,13 +4,12 @@
 
 #pragma once
 
+#include <stddef.h>  // for size_t
 #include <stdint.h>
-#include <stdlib.h>  // for size_t
 #include "../Configuration.hpp"
 #include "../Polyfills/math.hpp"
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 template <typename T, size_t = sizeof(T)>
 struct FloatTraits {};
@@ -167,5 +166,4 @@ struct FloatTraits<T, 4 /*32bits*/> {
     return forge(0x7f800000);
   }
 };
-}  // namespace Internals
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Numbers/isFloat.hpp

@@ -7,8 +7,7 @@
 #include <string.h>  // for strcmp
 #include "../Polyfills/ctype.hpp"
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 inline bool isFloat(const char* s) {
   if (!s) return false;
@@ -34,5 +33,4 @@ inline bool isFloat(const char* s) {
 
   return *s == '\0';
 }
-}  // namespace Internals
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Numbers/isInteger.hpp

@@ -6,8 +6,7 @@
 
 #include "../Polyfills/ctype.hpp"
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 inline bool isInteger(const char* s) {
   if (!s || !*s) return false;
@@ -15,5 +14,4 @@ inline bool isInteger(const char* s) {
   while (isdigit(*s)) s++;
   return *s == '\0';
 }
-}  // namespace Internals
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Numbers/parseFloat.hpp

@@ -8,8 +8,7 @@
 #include "../Polyfills/ctype.hpp"
 #include "../Polyfills/math.hpp"
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 template <typename T>
 inline T parseFloat(const char* s) {
@@ -86,5 +85,4 @@ inline T parseFloat(const char* s) {
 
   return negative_result ? -result : result;
 }
-}  // namespace Internals
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Numbers/parseInteger.hpp

@@ -4,13 +4,10 @@
 
 #pragma once
 
-#include <stdlib.h>
-
 #include "../Configuration.hpp"
 #include "../Polyfills/ctype.hpp"
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 template <typename T>
 T parseInteger(const char *s) {
   if (!s) return 0;  // NULL
@@ -37,5 +34,4 @@ T parseInteger(const char *s) {
 
   return negative_result ? T(~result + 1) : result;
 }
-}  // namespace Internals
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Polyfills/assert.hpp

@@ -0,0 +1,12 @@
+// ArduinoJson - arduinojson.org
+// Copyright Benoit Blanchon 2014-2018
+// MIT License
+
+#pragma once
+
+#ifdef ARDUINOJSON_DEBUG
+#include <assert.h>
+#define ARDUINOJSON_ASSERT(X) assert(X)
+#else
+#define ARDUINOJSON_ASSERT(X) ((void)0)
+#endif

src/ArduinoJson/Polyfills/attributes.hpp

@@ -27,3 +27,9 @@
 #define DEPRECATED(msg)
 
 #endif
+
+#if __cplusplus >= 201103L
+#define NOEXCEPT noexcept
+#else
+#define NOEXCEPT throw()
+#endif

src/ArduinoJson/Polyfills/ctype.hpp

@@ -4,8 +4,7 @@
 
 #pragma once
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 inline bool isdigit(char c) {
   return '0' <= c && c <= '9';
@@ -14,5 +13,4 @@ inline bool isdigit(char c) {
 inline bool issign(char c) {
   return '-' == c || c == '+';
 }
-}
-}
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Polyfills/math.hpp

@@ -4,8 +4,7 @@
 
 #pragma once
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 // Some libraries #define isnan() and isinf() so we need to check before
 // using this name
@@ -23,5 +22,4 @@ bool isinf(T x) {
   return x != 0.0 && x * 2 == x;
 }
 #endif
-}  // namespace Internals
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Polyfills/mpl/max.hpp

@@ -4,10 +4,9 @@
 
 #pragma once
 
-#include <stdlib.h>  // for size_t
+#include <stddef.h>  // for size_t
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 // A meta-function that returns the highest value
 template <size_t X, size_t Y, bool MaxIsX = (X > Y)>
@@ -22,5 +21,4 @@ template <size_t X, size_t Y>
 struct Max<X, Y, false> {
   static const size_t value = Y;
 };
-}  // namespace Internals
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Polyfills/type_traits/enable_if.hpp

@@ -4,8 +4,7 @@
 
 #pragma once
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 // A meta-function that return the type T if Condition is true.
 template <bool Condition, typename T = void>
@@ -15,5 +14,4 @@ template <typename T>
 struct enable_if<true, T> {
   typedef T type;
 };
-}  // namespace Internals
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE

src/ArduinoJson/Polyfills/type_traits/integral_constant.hpp

@@ -4,8 +4,7 @@
 
 #pragma once
 
-namespace ArduinoJson {
-namespace Internals {
+namespace ARDUINOJSON_NAMESPACE {
 
 template <typename T, T v>
 struct integral_constant {
@@ -15,5 +14,4 @@ struct integral_constant {
 typedef integral_constant<bool, true> true_type;
 typedef integral_constant<bool, false> false_type;
 
-}  // namespace Internals
-}  // namespace ArduinoJson
+}  // namespace ARDUINOJSON_NAMESPACE