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diff --git a/include/jsoncons/json_decoder.hpp b/include/jsoncons/json_decoder.hpp
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+++ b/include/jsoncons/json_decoder.hpp
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+// Copyright 2013-2016 Daniel Parker
+// Distributed under the Boost license, Version 1.0.
+// (See accompanying file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+
+// See https://github.com/danielaparker/jsoncons for latest version
+
+#ifndef JSONCONS_JSON_DECODER_HPP
+#define JSONCONS_JSON_DECODER_HPP
+
+#include <string>
+#include <vector>
+#include <type_traits> // std::true_type
+#include <memory> // std::allocator
+#include <iterator> // std::make_move_iterator
+#include <utility> // std::move
+#include <jsoncons/json_exception.hpp>
+#include <jsoncons/json_visitor.hpp>
+
+namespace jsoncons {
+
+template <class Json,class TempAllocator=std::allocator<char>>
+class json_decoder final : public basic_json_visitor<typename Json::char_type>
+{
+public:
+    using char_type = typename Json::char_type;
+    using typename basic_json_visitor<char_type>::string_view_type;
+
+    using key_value_type = typename Json::key_value_type;
+    using key_type = typename Json::key_type;
+    using array = typename Json::array;
+    using object = typename Json::object;
+    using result_allocator_type = typename Json::allocator_type;
+    using json_string_allocator = typename key_type::allocator_type;
+    using json_array_allocator = typename array::allocator_type;
+    using json_object_allocator = typename object::allocator_type;
+    typedef typename std::allocator_traits<result_allocator_type>:: template rebind_alloc<uint8_t> json_byte_allocator_type;
+private:
+    struct stack_item
+    {
+        key_type name_;
+        Json value_;
+
+        template <class... Args>
+        stack_item(key_type&& name, Args&& ... args) 
+            : name_(std::move(name)), value_(std::forward<Args>(args)...)
+        {
+        }
+
+        stack_item() = default;
+        stack_item(const stack_item&) = default;
+        stack_item(stack_item&&) = default;
+        stack_item& operator=(const stack_item&) = default;
+        stack_item& operator=(stack_item&&) = default;
+    };
+
+    enum class structure_type {root_t, array_t, object_t};
+
+    struct structure_info
+    {
+        structure_type type_;
+        std::size_t container_index_;
+
+        structure_info(structure_type type, std::size_t offset) noexcept
+            : type_(type), container_index_(offset)
+        {
+        }
+
+    };
+
+    using temp_allocator_type = TempAllocator;
+    typedef typename std::allocator_traits<temp_allocator_type>:: template rebind_alloc<stack_item> stack_item_allocator_type;
+    typedef typename std::allocator_traits<temp_allocator_type>:: template rebind_alloc<structure_info> structure_info_allocator_type;
+ 
+    result_allocator_type result_allocator_;
+    temp_allocator_type temp_allocator_;
+
+    Json result_;
+
+    key_type name_;
+    std::vector<stack_item,stack_item_allocator_type> item_stack_;
+    std::vector<structure_info,structure_info_allocator_type> structure_stack_;
+    bool is_valid_;
+
+public:
+    json_decoder(const temp_allocator_type& temp_alloc = temp_allocator_type())
+        : result_allocator_(result_allocator_type()),
+          temp_allocator_(temp_alloc),
+          result_(),
+          name_(result_allocator_),
+          item_stack_(temp_allocator_),
+          structure_stack_(temp_allocator_),
+          is_valid_(false) 
+    {
+        item_stack_.reserve(1000);
+        structure_stack_.reserve(100);
+        structure_stack_.emplace_back(structure_type::root_t, 0);
+    }
+
+    json_decoder(result_allocator_arg_t,
+                 const result_allocator_type& result_alloc)
+        : result_allocator_(result_alloc),
+          temp_allocator_(),
+          result_(),
+          name_(result_allocator_),
+          item_stack_(),
+          structure_stack_(),
+          is_valid_(false)
+    {
+        item_stack_.reserve(1000);
+        structure_stack_.reserve(100);
+        structure_stack_.emplace_back(structure_type::root_t, 0);
+    }
+
+    json_decoder(result_allocator_arg_t,
+                 const result_allocator_type& result_alloc, 
+                 const temp_allocator_type& temp_alloc)
+        : result_allocator_(result_alloc),
+          temp_allocator_(temp_alloc),
+          result_(),
+          name_(result_allocator_),
+          item_stack_(temp_allocator_),
+          structure_stack_(temp_allocator_),
+          is_valid_(false)
+    {
+        item_stack_.reserve(1000);
+        structure_stack_.reserve(100);
+        structure_stack_.emplace_back(structure_type::root_t, 0);
+    }
+
+    void reset()
+    {
+        is_valid_ = false;
+        item_stack_.clear();
+        structure_stack_.clear();
+        structure_stack_.emplace_back(structure_type::root_t, 0);
+    }
+
+    bool is_valid() const
+    {
+        return is_valid_;
+    }
+
+    Json get_result()
+    {
+        JSONCONS_ASSERT(is_valid_);
+        is_valid_ = false;
+        return std::move(result_);
+    }
+
+#if !defined(JSONCONS_NO_DEPRECATED)
+    JSONCONS_DEPRECATED_MSG("Instead, use get_result()")
+    Json& root()
+    {
+        return result_;
+    }
+#endif
+
+private:
+
+    void visit_flush() override
+    {
+    }
+
+    bool visit_begin_object(semantic_tag tag, const ser_context&, std::error_code&) override
+    {
+        if (structure_stack_.back().type_ == structure_type::root_t)
+        {
+            item_stack_.clear();
+            is_valid_ = false;
+        }
+        item_stack_.emplace_back(std::forward<key_type>(name_), json_object_arg, tag, result_allocator_);
+        structure_stack_.emplace_back(structure_type::object_t, item_stack_.size()-1);
+        return true;
+    }
+
+    bool visit_end_object(const ser_context&, std::error_code&) override
+    {
+        JSONCONS_ASSERT(structure_stack_.size() > 0);
+        JSONCONS_ASSERT(structure_stack_.back().type_ == structure_type::object_t);
+        const size_t structure_index = structure_stack_.back().container_index_;
+        JSONCONS_ASSERT(item_stack_.size() > structure_index);
+        const size_t count = item_stack_.size() - (structure_index + 1);
+        auto first = item_stack_.begin() + (structure_index+1);
+        auto last = first + count;
+        item_stack_[structure_index].value_.object_value().insert(
+            std::make_move_iterator(first),
+            std::make_move_iterator(last),
+            [](stack_item&& val){return key_value_type(std::move(val.name_), std::move(val.value_));}
+        );
+        item_stack_.erase(item_stack_.begin()+structure_index+1, item_stack_.end());
+        structure_stack_.pop_back();
+        if (structure_stack_.back().type_ == structure_type::root_t)
+        {
+            result_.swap(item_stack_.front().value_);
+            item_stack_.pop_back();
+            is_valid_ = true;
+            return false;
+        }
+        return true;
+    }
+
+    bool visit_begin_array(semantic_tag tag, const ser_context&, std::error_code&) override
+    {
+        if (structure_stack_.back().type_ == structure_type::root_t)
+        {
+            item_stack_.clear();
+            is_valid_ = false;
+        }
+        item_stack_.emplace_back(std::forward<key_type>(name_), json_array_arg, tag, result_allocator_);
+        structure_stack_.emplace_back(structure_type::array_t, item_stack_.size()-1);
+        return true;
+    }
+
+    bool visit_end_array(const ser_context&, std::error_code&) override
+    {
+        JSONCONS_ASSERT(structure_stack_.size() > 1);
+        JSONCONS_ASSERT(structure_stack_.back().type_ == structure_type::array_t);
+        const size_t container_index = structure_stack_.back().container_index_;
+        JSONCONS_ASSERT(item_stack_.size() > container_index);
+
+        auto& container = item_stack_[container_index].value_;
+
+        const size_t size = item_stack_.size() - (container_index + 1);
+        //std::cout << "size on item stack: " << size << "\n";
+
+        if (size > 0)
+        {
+            container.reserve(size);
+            auto first = item_stack_.begin() + (container_index+1);
+            auto last = first + size;
+            for (auto it = first; it != last; ++it)
+            {
+                container.push_back(std::move(it->value_));
+            }
+            item_stack_.erase(first, item_stack_.end());
+        }
+
+        structure_stack_.pop_back();
+        if (structure_stack_.back().type_ == structure_type::root_t)
+        {
+            result_.swap(item_stack_.front().value_);
+            item_stack_.pop_back();
+            is_valid_ = true;
+            return false;
+        }
+        return true;
+    }
+
+    bool visit_key(const string_view_type& name, const ser_context&, std::error_code&) override
+    {
+        name_ = key_type(name.data(),name.length(),result_allocator_);
+        return true;
+    }
+
+    bool visit_string(const string_view_type& sv, semantic_tag tag, const ser_context&, std::error_code&) override
+    {
+        switch (structure_stack_.back().type_)
+        {
+            case structure_type::object_t:
+            case structure_type::array_t:
+                item_stack_.emplace_back(std::forward<key_type>(name_), sv, tag, result_allocator_);
+                break;
+            case structure_type::root_t:
+                result_ = Json(sv, tag, result_allocator_);
+                is_valid_ = true;
+                return false;
+        }
+        return true;
+    }
+
+    bool visit_byte_string(const byte_string_view& b, 
+                           semantic_tag tag, 
+                           const ser_context&,
+                           std::error_code&) override
+    {
+        switch (structure_stack_.back().type_)
+        {
+            case structure_type::object_t:
+            case structure_type::array_t:
+                item_stack_.emplace_back(std::forward<key_type>(name_), byte_string_arg, b, tag, result_allocator_);
+                break;
+            case structure_type::root_t:
+                result_ = Json(byte_string_arg, b, tag, result_allocator_);
+                is_valid_ = true;
+                return false;
+        }
+        return true;
+    }
+
+    bool visit_byte_string(const byte_string_view& b, 
+                           uint64_t ext_tag, 
+                           const ser_context&,
+                           std::error_code&) override
+    {
+        switch (structure_stack_.back().type_)
+        {
+            case structure_type::object_t:
+            case structure_type::array_t:
+                item_stack_.emplace_back(std::forward<key_type>(name_), byte_string_arg, b, ext_tag, result_allocator_);
+                break;
+            case structure_type::root_t:
+                result_ = Json(byte_string_arg, b, ext_tag, result_allocator_);
+                is_valid_ = true;
+                return false;
+        }
+        return true;
+    }
+
+    bool visit_int64(int64_t value, 
+                        semantic_tag tag, 
+                        const ser_context&,
+                        std::error_code&) override
+    {
+        switch (structure_stack_.back().type_)
+        {
+            case structure_type::object_t:
+            case structure_type::array_t:
+                item_stack_.emplace_back(std::forward<key_type>(name_), value, tag);
+                break;
+            case structure_type::root_t:
+                result_ = Json(value,tag);
+                is_valid_ = true;
+                return false;
+        }
+        return true;
+    }
+
+    bool visit_uint64(uint64_t value, 
+                         semantic_tag tag, 
+                         const ser_context&,
+                         std::error_code&) override
+    {
+        switch (structure_stack_.back().type_)
+        {
+            case structure_type::object_t:
+            case structure_type::array_t:
+                item_stack_.emplace_back(std::forward<key_type>(name_), value, tag);
+                break;
+            case structure_type::root_t:
+                result_ = Json(value,tag);
+                is_valid_ = true;
+                return false;
+        }
+        return true;
+    }
+
+    bool visit_half(uint16_t value, 
+                       semantic_tag tag,   
+                       const ser_context&,
+                       std::error_code&) override
+    {
+        switch (structure_stack_.back().type_)
+        {
+            case structure_type::object_t:
+            case structure_type::array_t:
+                item_stack_.emplace_back(std::forward<key_type>(name_), half_arg, value, tag);
+                break;
+            case structure_type::root_t:
+                result_ = Json(half_arg, value, tag);
+                is_valid_ = true;
+                return false;
+        }
+        return true;
+    }
+
+    bool visit_double(double value, 
+                         semantic_tag tag,   
+                         const ser_context&,
+                         std::error_code&) override
+    {
+        switch (structure_stack_.back().type_)
+        {
+            case structure_type::object_t:
+            case structure_type::array_t:
+                item_stack_.emplace_back(std::forward<key_type>(name_), value, tag);
+                break;
+            case structure_type::root_t:
+                result_ = Json(value, tag);
+                is_valid_ = true;
+                return false;
+        }
+        return true;
+    }
+
+    bool visit_bool(bool value, semantic_tag tag, const ser_context&, std::error_code&) override
+    {
+        switch (structure_stack_.back().type_)
+        {
+            case structure_type::object_t:
+            case structure_type::array_t:
+                item_stack_.emplace_back(std::forward<key_type>(name_), value, tag);
+                break;
+            case structure_type::root_t:
+                result_ = Json(value, tag);
+                is_valid_ = true;
+                return false;
+        }
+        return true;
+    }
+
+    bool visit_null(semantic_tag tag, const ser_context&, std::error_code&) override
+    {
+        switch (structure_stack_.back().type_)
+        {
+            case structure_type::object_t:
+            case structure_type::array_t:
+                item_stack_.emplace_back(std::forward<key_type>(name_), null_type(), tag);
+                break;
+            case structure_type::root_t:
+                result_ = Json(null_type(), tag);
+                is_valid_ = true;
+                return false;
+        }
+        return true;
+    }
+};
+
+}
+
+#endif