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1 files changed, 2097 insertions, 0 deletions

diff --git a/include/jsoncons_ext/csv/csv_parser.hpp b/include/jsoncons_ext/csv/csv_parser.hpp
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--- /dev/null
+++ b/include/jsoncons_ext/csv/csv_parser.hpp
@@ -0,0 +1,2097 @@
+// Copyright 2015 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_CSV_CSV_PARSER_HPP
+#define JSONCONS_CSV_CSV_PARSER_HPP
+
+#include <memory> // std::allocator
+#include <string>
+#include <sstream>
+#include <vector>
+#include <stdexcept>
+#include <system_error>
+#include <cctype>
+#include <jsoncons/json_exception.hpp>
+#include <jsoncons/json_visitor.hpp>
+#include <jsoncons/json_reader.hpp>
+#include <jsoncons/json_filter.hpp>
+#include <jsoncons/json.hpp>
+#include <jsoncons/detail/parse_number.hpp>
+#include <jsoncons_ext/csv/csv_error.hpp>
+#include <jsoncons_ext/csv/csv_options.hpp>
+
+namespace jsoncons { namespace csv {
+
+enum class csv_mode 
+{
+    initial,
+    header,
+    data,
+    subfields
+};
+
+enum class csv_parse_state 
+{
+    start,
+    cr, 
+    column_labels,
+    expect_comment_or_record,
+    expect_record,
+    end_record,
+    no_more_records,
+    comment,
+    between_values,
+    quoted_string,
+    unquoted_string,
+    before_unquoted_string,
+    escaped_value,
+    minus, 
+    zero,  
+    integer,
+    fraction,
+    exp1,
+    exp2,
+    exp3,
+    accept,
+    before_unquoted_field,
+    before_unquoted_field_tail, 
+    before_unquoted_field_tail1,
+    before_last_unquoted_field,
+    before_last_unquoted_field_tail,
+    before_unquoted_subfield,
+    before_unquoted_subfield_tail,
+    before_quoted_subfield,
+    before_quoted_subfield_tail,
+    before_quoted_field,
+    before_quoted_field_tail,
+    before_last_quoted_field,
+    before_last_quoted_field_tail,
+    done
+};
+
+enum class cached_state
+{
+    begin_object,
+    end_object,
+    begin_array,
+    end_array,
+    name,
+    item,
+    done
+};
+
+struct default_csv_parsing
+{
+    bool operator()(csv_errc, const ser_context&) noexcept
+    {
+        return false;
+    }
+};
+
+namespace detail {
+
+    template <class CharT,class TempAllocator>
+    class parse_event
+    {
+        using temp_allocator_type = TempAllocator;
+        using string_view_type = typename basic_json_visitor<CharT>::string_view_type;
+        using char_allocator_type = typename std::allocator_traits<temp_allocator_type>:: template rebind_alloc<CharT>;
+        using byte_allocator_type = typename std::allocator_traits<temp_allocator_type>:: template rebind_alloc<uint8_t>;                  
+        using string_type = std::basic_string<CharT,std::char_traits<CharT>,char_allocator_type>;
+        using byte_string_type = basic_byte_string<byte_allocator_type>;
+
+        staj_event_type event_type;
+        string_type string_value;
+        byte_string_type byte_string_value;
+        union
+        {
+            bool bool_value;
+            int64_t int64_value;
+            uint64_t uint64_value;
+            double double_value;
+        };
+        semantic_tag tag;
+    public:
+        parse_event(staj_event_type event_type, semantic_tag tag, const TempAllocator& alloc)
+            : event_type(event_type), 
+              string_value(alloc),
+              byte_string_value(alloc),
+              tag(tag)
+        {
+        }
+
+        parse_event(const string_view_type& value, semantic_tag tag, const TempAllocator& alloc)
+            : event_type(staj_event_type::string_value), 
+              string_value(value.data(),value.length(),alloc), 
+              byte_string_value(alloc),
+              tag(tag)
+        {
+        }
+
+        parse_event(const byte_string_view& value, semantic_tag tag, const TempAllocator& alloc)
+            : event_type(staj_event_type::byte_string_value), 
+              string_value(alloc),
+              byte_string_value(value.data(),value.size(),alloc), 
+              tag(tag)
+        {
+        }
+
+        parse_event(bool value, semantic_tag tag, const TempAllocator& alloc)
+            : event_type(staj_event_type::bool_value), 
+              string_value(alloc),
+              byte_string_value(alloc),
+              bool_value(value), 
+              tag(tag)
+        {
+        }
+
+        parse_event(int64_t value, semantic_tag tag, const TempAllocator& alloc)
+            : event_type(staj_event_type::int64_value), 
+              string_value(alloc),
+              byte_string_value(alloc),
+              int64_value(value), 
+              tag(tag)
+        {
+        }
+
+        parse_event(uint64_t value, semantic_tag tag, const TempAllocator& alloc)
+            : event_type(staj_event_type::uint64_value), 
+              string_value(alloc),
+              byte_string_value(alloc),
+              uint64_value(value), 
+              tag(tag)
+        {
+        }
+
+        parse_event(double value, semantic_tag tag, const TempAllocator& alloc)
+            : event_type(staj_event_type::double_value), 
+              string_value(alloc),
+              byte_string_value(alloc),
+              double_value(value), 
+              tag(tag)
+        {
+        }
+
+        parse_event(const parse_event&) = default;
+        parse_event(parse_event&&) = default;
+        parse_event& operator=(const parse_event&) = default;
+        parse_event& operator=(parse_event&&) = default;
+
+        bool replay(basic_json_visitor<CharT>& visitor) const
+        {
+            switch (event_type)
+            {
+                case staj_event_type::begin_array:
+                    return visitor.begin_array(tag, ser_context());
+                case staj_event_type::end_array:
+                    return visitor.end_array(ser_context());
+                case staj_event_type::string_value:
+                    return visitor.string_value(string_value, tag, ser_context());
+                case staj_event_type::byte_string_value:
+                case staj_event_type::null_value:
+                    return visitor.null_value(tag, ser_context());
+                case staj_event_type::bool_value:
+                    return visitor.bool_value(bool_value, tag, ser_context());
+                case staj_event_type::int64_value:
+                    return visitor.int64_value(int64_value, tag, ser_context());
+                case staj_event_type::uint64_value:
+                    return visitor.uint64_value(uint64_value, tag, ser_context());
+                case staj_event_type::double_value:
+                    return visitor.double_value(double_value, tag, ser_context());
+                default:
+                    return false;
+            }
+        }
+    };
+
+    template <class CharT, class TempAllocator>
+    class m_columns_filter : public basic_json_visitor<CharT>
+    {
+    public:
+        using string_view_type = typename basic_json_visitor<CharT>::string_view_type;
+        using char_type = CharT;
+        using temp_allocator_type = TempAllocator;
+
+        using char_allocator_type = typename std::allocator_traits<temp_allocator_type>:: template rebind_alloc<CharT>;
+        using string_type = std::basic_string<CharT,std::char_traits<CharT>,char_allocator_type>;
+
+        using string_allocator_type = typename std::allocator_traits<temp_allocator_type>:: template rebind_alloc<string_type>;
+        using parse_event_allocator_type = typename std::allocator_traits<temp_allocator_type>:: template rebind_alloc<parse_event<CharT,TempAllocator>>;
+        using parse_event_vector_type = std::vector<parse_event<CharT,TempAllocator>, parse_event_allocator_type>;
+        using parse_event_vector_allocator_type = typename std::allocator_traits<temp_allocator_type>:: template rebind_alloc<parse_event_vector_type>;
+    private:
+        TempAllocator alloc_;
+        std::size_t name_index_;
+        int level_;
+        cached_state state_;
+        std::size_t column_index_;
+        std::size_t row_index_;
+
+        std::vector<string_type, string_allocator_type> column_names_;
+        std::vector<parse_event_vector_type,parse_event_vector_allocator_type> cached_events_;
+    public:
+
+        m_columns_filter(const TempAllocator& alloc)
+            : alloc_(alloc),
+              name_index_(0), 
+              level_(0), 
+              state_(cached_state::begin_object), 
+              column_index_(0), 
+              row_index_(0),
+              column_names_(alloc),
+              cached_events_(alloc)
+        {
+        }
+
+        void reset()
+        {
+            name_index_ = 0;
+            level_ = 0;
+            state_ = cached_state::begin_object;
+            column_index_ = 0;
+            row_index_ = 0;
+            column_names_.clear();
+            cached_events_.clear();
+        }
+
+        bool done() const
+        {
+            return state_ == cached_state::done;
+        }
+
+        void initialize(const std::vector<string_type, string_allocator_type>& column_names)
+        {
+            for (const auto& name : column_names)
+            {
+                column_names_.push_back(name);
+                cached_events_.emplace_back(alloc_);
+            }
+            name_index_ = 0;
+            level_ = 0;
+            column_index_ = 0;
+            row_index_ = 0;
+            state_ = cached_state::begin_object;
+        }
+
+        void skip_column()
+        {
+            ++name_index_;
+        }
+
+        bool replay_parse_events(basic_json_visitor<CharT>& visitor)
+        {
+            bool more = true;
+            while (more)
+            {
+                switch (state_)
+                {
+                    case cached_state::begin_object:
+                        more = visitor.begin_object(semantic_tag::none, ser_context());
+                        column_index_ = 0;
+                        state_ = cached_state::name;
+                        break;
+                    case cached_state::end_object:
+                        more = visitor.end_object(ser_context());
+                        state_ = cached_state::done;
+                        break;
+                    case cached_state::name:
+                        if (column_index_ < column_names_.size())
+                        {
+                            more = visitor.key(column_names_[column_index_], ser_context());
+                            state_ = cached_state::begin_array;
+                        }
+                        else
+                        {
+                            state_ = cached_state::end_object;
+                        }
+                        break;
+                    case cached_state::begin_array:
+                        more = visitor.begin_array(semantic_tag::none, ser_context());
+                        row_index_ = 0;
+                        state_ = cached_state::item;
+                        break;
+                    case cached_state::end_array:
+                        more = visitor.end_array(ser_context());
+                        ++column_index_;
+                        state_ = cached_state::name;
+                        break;
+                    case cached_state::item:
+                        if (row_index_ < cached_events_[column_index_].size())
+                        {
+                            more = cached_events_[column_index_][row_index_].replay(visitor);
+                            ++row_index_;
+                        }
+                        else
+                        {
+                            state_ = cached_state::end_array;
+                        }
+                        break;
+                    default:
+                        more = false;
+                        break;
+                }
+            }
+            return more;
+        }
+
+        void visit_flush() override
+        {
+        }
+
+        bool visit_begin_object(semantic_tag, const ser_context&, std::error_code& ec) override
+        {
+            ec = csv_errc::invalid_parse_state;
+            return false;
+        }
+
+        bool visit_end_object(const ser_context&, std::error_code& ec) override
+        {
+            ec = csv_errc::invalid_parse_state;
+            return false;
+        }
+
+        bool visit_begin_array(semantic_tag tag, const ser_context&, std::error_code&) override
+        {
+            if (name_index_ < column_names_.size())
+            {
+                cached_events_[name_index_].emplace_back(staj_event_type::begin_array, tag, alloc_);
+                
+                ++level_;
+            }
+            return true;
+        }
+
+        bool visit_end_array(const ser_context&, std::error_code&) override
+        {
+            if (level_ > 0)
+            {
+                cached_events_[name_index_].emplace_back(staj_event_type::end_array, semantic_tag::none, alloc_);
+                ++name_index_;
+                --level_;
+            }
+            else
+            {
+                name_index_ = 0;
+            }
+            return true;
+        }
+
+        bool visit_key(const string_view_type&, const ser_context&, std::error_code& ec) override
+        {
+            ec = csv_errc::invalid_parse_state;
+            return false;
+        }
+
+        bool visit_null(semantic_tag tag, const ser_context&, std::error_code&) override
+        {
+            if (name_index_ < column_names_.size())
+            {
+                cached_events_[name_index_].emplace_back(staj_event_type::null_value, tag, alloc_);
+                if (level_ == 0)
+                {
+                    ++name_index_;
+                }
+            }
+            return true;
+        }
+
+        bool visit_string(const string_view_type& value, semantic_tag tag, const ser_context&, std::error_code&) override
+        {
+            if (name_index_ < column_names_.size())
+            {
+                cached_events_[name_index_].emplace_back(value, tag, alloc_);
+
+                if (level_ == 0)
+                {
+                    ++name_index_;
+                }
+            }
+            return true;
+        }
+
+        bool visit_byte_string(const byte_string_view& value,
+                                  semantic_tag tag,
+                                  const ser_context&,
+                                  std::error_code&) override
+        {
+            if (name_index_ < column_names_.size())
+            {
+                cached_events_[name_index_].emplace_back(value, tag, alloc_);
+                if (level_ == 0)
+                {
+                    ++name_index_;
+                }
+            }
+            return true;
+        }
+
+        bool visit_double(double value,
+                             semantic_tag tag, 
+                             const ser_context&,
+                             std::error_code&) override
+        {
+            if (name_index_ < column_names_.size())
+            {
+                cached_events_[name_index_].emplace_back(value, tag, alloc_);
+                if (level_ == 0)
+                {
+                    ++name_index_;
+                }
+            }
+            return true;
+        }
+
+        bool visit_int64(int64_t value,
+                            semantic_tag tag,
+                            const ser_context&,
+                            std::error_code&) override
+        {
+            if (name_index_ < column_names_.size())
+            {
+                cached_events_[name_index_].emplace_back(value, tag, alloc_);
+                if (level_ == 0)
+                {
+                    ++name_index_;
+                }
+            }
+            return true;
+        }
+
+        bool visit_uint64(uint64_t value,
+                             semantic_tag tag,
+                             const ser_context&,
+                             std::error_code&) override
+        {
+            if (name_index_ < column_names_.size())
+            {
+                cached_events_[name_index_].emplace_back(value, tag, alloc_);
+                if (level_ == 0)
+                {
+                    ++name_index_;
+                }
+            }
+            return true;
+        }
+
+        bool visit_bool(bool value, semantic_tag tag, const ser_context&, std::error_code&) override
+        {
+            if (name_index_ < column_names_.size())
+            {
+                cached_events_[name_index_].emplace_back(value, tag, alloc_);
+                if (level_ == 0)
+                {
+                    ++name_index_;
+                }
+            }
+            return true;
+        }
+    };
+
+} // namespace detail
+
+template<class CharT,class TempAllocator=std::allocator<char>>
+class basic_csv_parser : public ser_context
+{
+public:
+    using string_view_type = jsoncons::basic_string_view<CharT>;
+    using char_type = CharT;
+private:
+    struct string_maps_to_double
+    {
+        string_view_type s;
+
+        bool operator()(const std::pair<string_view_type,double>& val) const
+        {
+            return val.first == s;
+        }
+    };
+
+    using temp_allocator_type = TempAllocator;
+    typedef typename std::allocator_traits<temp_allocator_type>:: template rebind_alloc<CharT> char_allocator_type;
+    using string_type = std::basic_string<CharT,std::char_traits<CharT>,char_allocator_type>;
+    typedef typename std::allocator_traits<temp_allocator_type>:: template rebind_alloc<string_type> string_allocator_type;
+    typedef typename std::allocator_traits<temp_allocator_type>:: template rebind_alloc<csv_mode> csv_mode_allocator_type;
+    typedef typename std::allocator_traits<temp_allocator_type>:: template rebind_alloc<csv_type_info> csv_type_info_allocator_type;
+    typedef typename std::allocator_traits<temp_allocator_type>:: template rebind_alloc<std::vector<string_type,string_allocator_type>> string_vector_allocator_type;
+    typedef typename std::allocator_traits<temp_allocator_type>:: template rebind_alloc<csv_parse_state> csv_parse_state_allocator_type;
+
+    static constexpr int default_depth = 3;
+
+    temp_allocator_type alloc_;
+    csv_parse_state state_;
+    basic_json_visitor<CharT>* visitor_;
+    std::function<bool(csv_errc,const ser_context&)> err_handler_;
+    std::size_t column_;
+    std::size_t line_;
+    int depth_;
+    const basic_csv_decode_options<CharT> options_;
+    std::size_t column_index_;
+    std::size_t level_;
+    std::size_t offset_;
+    jsoncons::detail::chars_to to_double_; 
+    const CharT* begin_input_;
+    const CharT* input_end_;
+    const CharT* input_ptr_;
+    bool more_;
+    std::size_t header_line_;
+
+    detail::m_columns_filter<CharT,TempAllocator> m_columns_filter_;
+    std::vector<csv_mode,csv_mode_allocator_type> stack_;
+    std::vector<string_type,string_allocator_type> column_names_;
+    std::vector<csv_type_info,csv_type_info_allocator_type> column_types_;
+    std::vector<string_type,string_allocator_type> column_defaults_;
+    std::vector<csv_parse_state,csv_parse_state_allocator_type> state_stack_;
+    string_type buffer_;
+    std::vector<std::pair<string_view_type,double>> string_double_map_;
+
+public:
+    basic_csv_parser(const TempAllocator& alloc = TempAllocator())
+       : basic_csv_parser(basic_csv_decode_options<CharT>(), 
+                          default_csv_parsing(),
+                          alloc)
+    {
+    }
+
+    basic_csv_parser(const basic_csv_decode_options<CharT>& options,
+                     const TempAllocator& alloc = TempAllocator())
+        : basic_csv_parser(options, 
+                           default_csv_parsing(),
+                           alloc)
+    {
+    }
+
+    basic_csv_parser(std::function<bool(csv_errc,const ser_context&)> err_handler,
+                     const TempAllocator& alloc = TempAllocator())
+        : basic_csv_parser(basic_csv_decode_options<CharT>(), 
+                           err_handler,
+                           alloc)
+    {
+    }
+
+    basic_csv_parser(const basic_csv_decode_options<CharT>& options,
+                     std::function<bool(csv_errc,const ser_context&)> err_handler,
+                     const TempAllocator& alloc = TempAllocator())
+       : alloc_(alloc),
+         state_(csv_parse_state::start),
+         visitor_(nullptr),
+         err_handler_(err_handler),
+         column_(1),
+         line_(1),
+         depth_(default_depth),
+         options_(options),
+         column_index_(0),
+         level_(0),
+         offset_(0),
+         begin_input_(nullptr),
+         input_end_(nullptr),
+         input_ptr_(nullptr),
+         more_(true),
+         header_line_(1),
+         m_columns_filter_(alloc),
+         stack_(alloc),
+         column_names_(alloc),
+         column_types_(alloc),
+         column_defaults_(alloc),
+         state_stack_(alloc),
+         buffer_(alloc)
+    {
+        if (options_.enable_str_to_nan())
+        {
+            string_double_map_.emplace_back(options_.nan_to_str(),std::nan(""));
+        }
+        if (options_.enable_str_to_inf())
+        {
+            string_double_map_.emplace_back(options_.inf_to_str(),std::numeric_limits<double>::infinity());
+        }
+        if (options_.enable_str_to_neginf())
+        {
+            string_double_map_.emplace_back(options_.neginf_to_str(),-std::numeric_limits<double>::infinity());
+        }
+
+        initialize();
+    }
+
+    ~basic_csv_parser() noexcept
+    {
+    }
+
+    bool done() const
+    {
+        return state_ == csv_parse_state::done;
+    }
+
+    bool accept() const
+    {
+        return state_ == csv_parse_state::accept || state_ == csv_parse_state::done;
+    }
+
+    bool stopped() const
+    {
+        return !more_;
+    }
+
+    bool source_exhausted() const
+    {
+        return input_ptr_ == input_end_;
+    }
+
+    const std::vector<string_type,string_allocator_type>& column_labels() const
+    {
+        return column_names_;
+    }
+
+    void reinitialize()
+    {
+        state_ = csv_parse_state::start;
+        visitor_ = nullptr;
+        column_ = 1;
+        line_ = 1;
+        depth_ = default_depth;
+        column_index_ = 0;
+        level_ = 0;
+        offset_ = 0;
+        begin_input_ = nullptr;
+        input_end_ = nullptr;
+        input_ptr_ = nullptr;
+        more_ = true;
+        header_line_ = 1;
+        m_columns_filter_.reset();
+        stack_.clear();
+        column_names_.clear();
+        column_types_.clear();
+        column_defaults_.clear();
+        state_stack_.clear();
+        buffer_.clear();
+
+        initialize();
+    }
+
+    void restart()
+    {
+        more_ = true;
+    }
+
+    void parse_some(basic_json_visitor<CharT>& visitor)
+    {
+        std::error_code ec;
+        parse_some(visitor,ec);
+        if (ec)
+        {
+            JSONCONS_THROW(ser_error(ec,line_,column_));
+        }
+    }
+
+    void parse_some(basic_json_visitor<CharT>& visitor, std::error_code& ec)
+    {
+        switch (options_.mapping_kind())
+        {
+            case csv_mapping_kind::m_columns:
+                visitor_ = &m_columns_filter_;
+                break;
+            default:
+                visitor_ = std::addressof(visitor);
+                break;
+        } 
+
+        const CharT* local_input_end = input_end_;
+
+        if (input_ptr_ == local_input_end && more_)
+        {
+            switch (state_)
+            {
+                case csv_parse_state::start:
+                    ec = csv_errc::source_error;
+                    more_ = false;
+                    return;
+                case csv_parse_state::before_unquoted_field:
+                case csv_parse_state::before_last_unquoted_field:
+                    end_unquoted_string_value(ec);
+                    state_ = csv_parse_state::before_last_unquoted_field_tail;
+                    break;
+                case csv_parse_state::before_last_unquoted_field_tail:
+                    if (stack_.back() == csv_mode::subfields)
+                    {
+                        stack_.pop_back();
+                        more_ = visitor_->end_array(*this, ec);
+                    }
+                    ++column_index_;
+                    state_ = csv_parse_state::end_record;
+                    break;
+                case csv_parse_state::before_unquoted_string: 
+                    buffer_.clear();
+                    JSONCONS_FALLTHROUGH;
+                case csv_parse_state::unquoted_string: 
+                    if (options_.trim_leading() || options_.trim_trailing())
+                    {
+                        trim_string_buffer(options_.trim_leading(),options_.trim_trailing());
+                    }
+                    if (options_.ignore_empty_values() && buffer_.empty())
+                    {
+                        state_ = csv_parse_state::end_record;
+                    }
+                    else
+                    {
+                        before_value(ec);
+                        state_ = csv_parse_state::before_unquoted_field;
+                    }
+                    break;
+                case csv_parse_state::before_last_quoted_field:
+                    end_quoted_string_value(ec);
+                    ++column_index_;
+                    state_ = csv_parse_state::end_record;
+                    break;
+                case csv_parse_state::escaped_value:
+                    if (options_.quote_escape_char() == options_.quote_char())
+                    {
+                        if (!(options_.ignore_empty_values() && buffer_.empty()))
+                        {
+                            before_value(ec);
+                            ++column_;
+                            state_ = csv_parse_state::before_last_quoted_field;
+                        }
+                        else
+                        {
+                            state_ = csv_parse_state::end_record;
+                        }
+                    }
+                    else
+                    {
+                        ec = csv_errc::invalid_escaped_char;
+                        more_ = false;
+                        return;
+                    }
+                    break;
+                case csv_parse_state::end_record:
+                    if (column_index_ > 0)
+                    {
+                        after_record(ec);
+                    }
+                    state_ = csv_parse_state::no_more_records;
+                    break;
+                case csv_parse_state::no_more_records: 
+                    switch (stack_.back()) 
+                    {
+                        case csv_mode::header:
+                            stack_.pop_back();
+                            break;
+                        case csv_mode::data:
+                            stack_.pop_back();
+                            break;
+                        default:
+                            break;
+                    }
+                    more_ = visitor_->end_array(*this, ec);
+                    if (options_.mapping_kind() == csv_mapping_kind::m_columns)
+                    {
+                        if (!m_columns_filter_.done())
+                        {
+                            more_ = m_columns_filter_.replay_parse_events(visitor);
+                        }
+                        else
+                        {
+                            state_ = csv_parse_state::accept;
+                        }
+                    }
+                    else
+                    {
+                        state_ = csv_parse_state::accept;
+                    }
+                    break;
+                case csv_parse_state::accept:
+                    if (!(stack_.size() == 1 && stack_.back() == csv_mode::initial))
+                    {
+                        err_handler_(csv_errc::unexpected_eof, *this);
+                        ec = csv_errc::unexpected_eof;
+                        more_ = false;
+                        return;
+                    }
+                    stack_.pop_back();
+                    visitor_->flush();
+                    state_ = csv_parse_state::done;
+                    more_ = false;
+                    return;
+                default:
+                    state_ = csv_parse_state::end_record;
+                    break;
+            }
+        }
+
+        for (; (input_ptr_ < local_input_end) && more_;)
+        {
+            CharT curr_char = *input_ptr_;
+
+            switch (state_) 
+            {
+                case csv_parse_state::cr:
+                    ++line_;
+                    column_ = 1;
+                    switch (*input_ptr_)
+                    {
+                        case '\n':
+                            ++input_ptr_;
+                            state_ = pop_state();
+                            break;
+                        default:
+                            state_ = pop_state();
+                            break;
+                    }
+                    break;
+                case csv_parse_state::start:
+                    if (options_.mapping_kind() != csv_mapping_kind::m_columns)
+                    {
+                        more_ = visitor_->begin_array(semantic_tag::none, *this, ec);
+                    }
+                    if (options_.assume_header() && options_.mapping_kind() == csv_mapping_kind::n_rows && options_.column_names().size() > 0)
+                    {
+                        column_index_ = 0;
+                        state_ = csv_parse_state::column_labels;
+                        more_ = visitor_->begin_array(semantic_tag::none, *this, ec);
+                        state_ = csv_parse_state::expect_comment_or_record;
+                    }
+                    else
+                    {
+                        state_ = csv_parse_state::expect_comment_or_record;
+                    }
+                    break;
+                case csv_parse_state::column_labels:
+                    if (column_index_ < column_names_.size())
+                    {
+                        more_ = visitor_->string_value(column_names_[column_index_], semantic_tag::none, *this, ec);
+                        ++column_index_;
+                    }
+                    else
+                    {
+                        more_ = visitor_->end_array(*this, ec);
+                        state_ = csv_parse_state::expect_comment_or_record; 
+                        //stack_.back() = csv_mode::data;
+                        column_index_ = 0;
+                    }
+                    break;
+                case csv_parse_state::comment: 
+                    switch (curr_char)
+                    {
+                        case '\n':
+                        {
+                            ++line_;
+                            if (stack_.back() == csv_mode::header)
+                            {
+                                ++header_line_;
+                            }
+                            column_ = 1;
+                            state_ = csv_parse_state::expect_comment_or_record;
+                            break;
+                        }
+                        case '\r':
+                            ++line_;
+                            if (stack_.back() == csv_mode::header)
+                            {
+                                ++header_line_;
+                            }
+                            column_ = 1;
+                            state_ = csv_parse_state::expect_comment_or_record;
+                            push_state(state_);
+                            state_ = csv_parse_state::cr;
+                            break;
+                        default:
+                            ++column_;
+                            break;
+                    }
+                    ++input_ptr_;
+                    break;
+                
+                case csv_parse_state::expect_comment_or_record:
+                    buffer_.clear();
+                    if (curr_char == options_.comment_starter())
+                    {
+                        state_ = csv_parse_state::comment;
+                        ++column_;
+                        ++input_ptr_;
+                    }
+                    else
+                    {
+                        state_ = csv_parse_state::expect_record;
+                    }
+                    break;
+                case csv_parse_state::quoted_string: 
+                    {
+                        if (curr_char == options_.quote_escape_char())
+                        {
+                            state_ = csv_parse_state::escaped_value;
+                        }
+                        else if (curr_char == options_.quote_char())
+                        {
+                            state_ = csv_parse_state::between_values;
+                        }
+                        else
+                        {
+                            buffer_.push_back(static_cast<CharT>(curr_char));
+                        }
+                    }
+                    ++column_;
+                    ++input_ptr_;
+                    break;
+                case csv_parse_state::escaped_value: 
+                    {
+                        if (curr_char == options_.quote_char())
+                        {
+                            buffer_.push_back(static_cast<CharT>(curr_char));
+                            state_ = csv_parse_state::quoted_string;
+                            ++column_;
+                            ++input_ptr_;
+                        }
+                        else if (options_.quote_escape_char() == options_.quote_char())
+                        {
+                            state_ = csv_parse_state::between_values;
+                        }
+                        else
+                        {
+                            ec = csv_errc::invalid_escaped_char;
+                            more_ = false;
+                            return;
+                        }
+                    }
+                    break;
+                case csv_parse_state::between_values:
+                    switch (curr_char)
+                    {
+                        case '\r':
+                        case '\n':
+                        {
+                            if (options_.trim_leading() || options_.trim_trailing())
+                            {
+                                trim_string_buffer(options_.trim_leading(),options_.trim_trailing());
+                            }
+                            if (!(options_.ignore_empty_values() && buffer_.empty()))
+                            {
+                                before_value(ec);
+                                state_ = csv_parse_state::before_last_quoted_field;
+                            }
+                            else
+                            {
+                                state_ = csv_parse_state::end_record;
+                            }
+                            break;
+                        }
+                        default:
+                            if (curr_char == options_.field_delimiter())
+                            {
+                                if (options_.trim_leading() || options_.trim_trailing())
+                                {
+                                    trim_string_buffer(options_.trim_leading(),options_.trim_trailing());
+                                }
+                                before_value(ec);
+                                state_ = csv_parse_state::before_quoted_field;
+                            }
+                            else if (options_.subfield_delimiter() != char_type() && curr_char == options_.subfield_delimiter())
+                            {
+                                if (options_.trim_leading() || options_.trim_trailing())
+                                {
+                                    trim_string_buffer(options_.trim_leading(),options_.trim_trailing());
+                                }
+                                before_value(ec);
+                                state_ = csv_parse_state::before_quoted_subfield;
+                            }
+                            else if (curr_char == ' ' || curr_char == '\t')
+                            {
+                                ++column_;
+                                ++input_ptr_;
+                            }
+                            else
+                            {
+                                ec = csv_errc::unexpected_char_between_fields;
+                                more_ = false;
+                                return;
+                            }
+                            break;
+                    }
+                    break;
+                case csv_parse_state::before_unquoted_string: 
+                {
+                    buffer_.clear();
+                    state_ = csv_parse_state::unquoted_string;
+                    break;
+                }
+                case csv_parse_state::before_unquoted_field:
+                    end_unquoted_string_value(ec);
+                    state_ = csv_parse_state::before_unquoted_field_tail;
+                    break;
+                case csv_parse_state::before_unquoted_field_tail:
+                {
+                    if (stack_.back() == csv_mode::subfields)
+                    {
+                        stack_.pop_back();
+                        more_ = visitor_->end_array(*this, ec);
+                    }
+                    ++column_index_;
+                    state_ = csv_parse_state::before_unquoted_string;
+                    ++column_;
+                    ++input_ptr_;
+                    break;
+                }
+                case csv_parse_state::before_unquoted_field_tail1:
+                {
+                    if (stack_.back() == csv_mode::subfields)
+                    {
+                        stack_.pop_back();
+                        more_ = visitor_->end_array(*this, ec);
+                    }
+                    state_ = csv_parse_state::end_record;
+                    ++column_;
+                    ++input_ptr_;
+                    break;
+                }
+
+                case csv_parse_state::before_last_unquoted_field:
+                    end_unquoted_string_value(ec);
+                    state_ = csv_parse_state::before_last_unquoted_field_tail;
+                    break;
+
+                case csv_parse_state::before_last_unquoted_field_tail:
+                    if (stack_.back() == csv_mode::subfields)
+                    {
+                        stack_.pop_back();
+                        more_ = visitor_->end_array(*this, ec);
+                    }
+                    ++column_index_;
+                    state_ = csv_parse_state::end_record;
+                    break;
+
+                case csv_parse_state::before_unquoted_subfield:
+                    if (stack_.back() == csv_mode::data)
+                    {
+                        stack_.push_back(csv_mode::subfields);
+                        more_ = visitor_->begin_array(semantic_tag::none, *this, ec);
+                    }
+                    state_ = csv_parse_state::before_unquoted_subfield_tail;
+                    break; 
+                case csv_parse_state::before_unquoted_subfield_tail:
+                    end_unquoted_string_value(ec);
+                    state_ = csv_parse_state::before_unquoted_string;
+                    ++column_;
+                    ++input_ptr_;
+                    break;
+                case csv_parse_state::before_quoted_field:
+                    end_quoted_string_value(ec);
+                    state_ = csv_parse_state::before_unquoted_field_tail; // return to unquoted
+                    break;
+                case csv_parse_state::before_quoted_subfield:
+                    if (stack_.back() == csv_mode::data)
+                    {
+                        stack_.push_back(csv_mode::subfields);
+                        more_ = visitor_->begin_array(semantic_tag::none, *this, ec);
+                    }
+                    state_ = csv_parse_state::before_quoted_subfield_tail;
+                    break; 
+                case csv_parse_state::before_quoted_subfield_tail:
+                    end_quoted_string_value(ec);
+                    state_ = csv_parse_state::before_unquoted_string;
+                    ++column_;
+                    ++input_ptr_;
+                    break;
+                case csv_parse_state::before_last_quoted_field:
+                    end_quoted_string_value(ec);
+                    state_ = csv_parse_state::before_last_quoted_field_tail;
+                    break;
+                case csv_parse_state::before_last_quoted_field_tail:
+                    if (stack_.back() == csv_mode::subfields)
+                    {
+                        stack_.pop_back();
+                        more_ = visitor_->end_array(*this, ec);
+                    }
+                    ++column_index_;
+                    state_ = csv_parse_state::end_record;
+                    break;
+                case csv_parse_state::unquoted_string: 
+                {
+                    switch (curr_char)
+                    {
+                        case '\n':
+                        case '\r':
+                        {
+                            if (options_.trim_leading() || options_.trim_trailing())
+                            {
+                                trim_string_buffer(options_.trim_leading(),options_.trim_trailing());
+                            }
+                            if (!(options_.ignore_empty_values() && buffer_.empty()))
+                            {
+                                before_value(ec);
+                                state_ = csv_parse_state::before_last_unquoted_field;
+                            }
+                            else
+                            {
+                                state_ = csv_parse_state::end_record;
+                            }
+                            break;
+                        }
+                        default:
+                            if (curr_char == options_.field_delimiter())
+                            {
+                                if (options_.trim_leading() || options_.trim_trailing())
+                                {
+                                    trim_string_buffer(options_.trim_leading(),options_.trim_trailing());
+                                }
+                                before_value(ec);
+                                state_ = csv_parse_state::before_unquoted_field;
+                            }
+                            else if (options_.subfield_delimiter() != char_type() && curr_char == options_.subfield_delimiter())
+                            {
+                                if (options_.trim_leading() || options_.trim_trailing())
+                                {
+                                    trim_string_buffer(options_.trim_leading(),options_.trim_trailing());
+                                }
+                                before_value(ec);
+                                state_ = csv_parse_state::before_unquoted_subfield;
+                            }
+                            else if (curr_char == options_.quote_char())
+                            {
+                                buffer_.clear();
+                                state_ = csv_parse_state::quoted_string;
+                                ++column_;
+                                ++input_ptr_;
+                            }
+                            else
+                            {
+                                buffer_.push_back(static_cast<CharT>(curr_char));
+                                ++column_;
+                                ++input_ptr_;
+                            }
+                            break;
+                    }
+                    break;
+                }
+                case csv_parse_state::expect_record: 
+                {
+                    switch (curr_char)
+                    {
+                        case '\n':
+                        {
+                            if (!options_.ignore_empty_lines())
+                            {
+                                before_record(ec);
+                                state_ = csv_parse_state::end_record;
+                            }
+                            else
+                            {
+                                ++line_;
+                                column_ = 1;
+                                state_ = csv_parse_state::expect_comment_or_record;
+                                ++input_ptr_;
+                            }
+                            break;
+                        }
+                        case '\r':
+                            if (!options_.ignore_empty_lines())
+                            {
+                                before_record(ec);
+                                state_ = csv_parse_state::end_record;
+                            }
+                            else
+                            {
+                                ++line_;
+                                column_ = 1;
+                                state_ = csv_parse_state::expect_comment_or_record;
+                                ++input_ptr_;
+                                push_state(state_);
+                                state_ = csv_parse_state::cr;
+                            }
+                            break;
+                        case ' ':
+                        case '\t':
+                            if (!options_.trim_leading())
+                            {
+                                buffer_.push_back(static_cast<CharT>(curr_char));
+                                before_record(ec);
+                                state_ = csv_parse_state::unquoted_string;
+                            }
+                            ++column_;
+                            ++input_ptr_;
+                            break;
+                        default:
+                            before_record(ec);
+                            if (curr_char == options_.quote_char())
+                            {
+                                buffer_.clear();
+                                state_ = csv_parse_state::quoted_string;
+                                ++column_;
+                                ++input_ptr_;
+                            }
+                            else
+                            {
+                                state_ = csv_parse_state::unquoted_string;
+                            }
+                            break;
+                        }
+                    break;
+                    }
+                case csv_parse_state::end_record: 
+                {
+                    switch (curr_char)
+                    {
+                        case '\n':
+                        {
+                            ++line_;
+                            column_ = 1;
+                            state_ = csv_parse_state::expect_comment_or_record;
+                            after_record(ec);
+                            ++input_ptr_;
+                            break;
+                        }
+                        case '\r':
+                            ++line_;
+                            column_ = 1;
+                            state_ = csv_parse_state::expect_comment_or_record;
+                            after_record(ec);
+                            push_state(state_);
+                            state_ = csv_parse_state::cr;
+                            ++input_ptr_;
+                            break;
+                        case ' ':
+                        case '\t':
+                            ++column_;
+                            ++input_ptr_;
+                            break;
+                        default:
+                            err_handler_(csv_errc::syntax_error, *this);
+                            ec = csv_errc::syntax_error;
+                            more_ = false;
+                            return;
+                        }
+                    break;
+                }
+                default:
+                    err_handler_(csv_errc::invalid_parse_state, *this);
+                    ec = csv_errc::invalid_parse_state;
+                    more_ = false;
+                    return;
+            }
+            if (line_ > options_.max_lines())
+            {
+                state_ = csv_parse_state::done;
+                more_ = false;
+            }
+        }
+    }
+
+    void finish_parse()
+    {
+        std::error_code ec;
+        finish_parse(ec);
+        if (ec)
+        {
+            JSONCONS_THROW(ser_error(ec,line_,column_));
+        }
+    }
+
+    void finish_parse(std::error_code& ec)
+    {
+        while (more_)
+        {
+            parse_some(ec);
+        }
+    }
+
+    csv_parse_state state() const
+    {
+        return state_;
+    }
+
+    void update(const string_view_type sv)
+    {
+        update(sv.data(),sv.length());
+    }
+
+    void update(const CharT* data, std::size_t length)
+    {
+        begin_input_ = data;
+        input_end_ = data + length;
+        input_ptr_ = begin_input_;
+    }
+
+    std::size_t line() const override
+    {
+        return line_;
+    }
+
+    std::size_t column() const override
+    {
+        return column_;
+    }
+
+private:
+    void initialize()
+    {
+        jsoncons::csv::detail::parse_column_names(options_.column_names(), column_names_);
+        jsoncons::csv::detail::parse_column_types(options_.column_types(), column_types_);
+        jsoncons::csv::detail::parse_column_names(options_.column_defaults(), column_defaults_);
+
+        stack_.reserve(default_depth);
+        stack_.push_back(csv_mode::initial);
+        stack_.push_back((options_.header_lines() > 0) ? csv_mode::header
+                                                       : csv_mode::data);
+    }
+
+    // name
+    void before_value(std::error_code& ec)
+    {
+        switch (stack_.back())
+        {
+            case csv_mode::header:
+                if (options_.trim_leading_inside_quotes() || options_.trim_trailing_inside_quotes())
+                {
+                    trim_string_buffer(options_.trim_leading_inside_quotes(),options_.trim_trailing_inside_quotes());
+                }
+                if (line_ == header_line_)
+                {
+                    column_names_.push_back(buffer_);
+                    if (options_.assume_header() && options_.mapping_kind() == csv_mapping_kind::n_rows)
+                    {
+                        more_ = visitor_->string_value(buffer_, semantic_tag::none, *this, ec);
+                    }
+                }
+                break;
+            case csv_mode::data:
+                if (options_.mapping_kind() == csv_mapping_kind::n_objects)
+                {
+                    if (!(options_.ignore_empty_values() && buffer_.empty()))
+                    {
+                        if (column_index_ < column_names_.size() + offset_)
+                        {
+                            more_ = visitor_->key(column_names_[column_index_ - offset_], *this, ec);
+                        }
+                    }
+                }
+                break;
+            default:
+                break;
+        }
+    }
+
+    // begin_array or begin_record
+    void before_record(std::error_code& ec)
+    {
+        offset_ = 0;
+
+        switch (stack_.back())
+        {
+            case csv_mode::header:
+                if (options_.assume_header() && line_ == header_line_)
+                {
+                    if (options_.mapping_kind() == csv_mapping_kind::n_rows)
+                    {
+                        more_ = visitor_->begin_array(semantic_tag::none, *this, ec);
+                    }
+                }
+                break;
+            case csv_mode::data:
+                switch (options_.mapping_kind())
+                {
+                    case csv_mapping_kind::n_rows:
+                        more_ = visitor_->begin_array(semantic_tag::none, *this, ec);
+                        break;
+                    case csv_mapping_kind::n_objects:
+                        more_ = visitor_->begin_object(semantic_tag::none, *this, ec);
+                        break;
+                    case csv_mapping_kind::m_columns:
+                        break;
+                    default:
+                        break;
+                }
+                break;
+            default:
+                break;
+        }
+    }
+
+    // end_array, begin_array, string_value (headers)
+    void after_record(std::error_code& ec)
+    {
+        if (column_types_.size() > 0)
+        {
+            if (level_ > 0)
+            {
+                more_ = visitor_->end_array(*this, ec);
+                level_ = 0;
+            }
+        }
+        switch (stack_.back())
+        {
+            case csv_mode::header:
+                if (line_ >= options_.header_lines())
+                {
+                    stack_.back() = csv_mode::data;
+                }
+                switch (options_.mapping_kind())
+                {
+                    case csv_mapping_kind::n_rows:
+                        if (options_.assume_header())
+                        {
+                            more_ = visitor_->end_array(*this, ec);
+                        }
+                        break;
+                    case csv_mapping_kind::m_columns:
+                        m_columns_filter_.initialize(column_names_);
+                        break;
+                    default:
+                        break;
+                }
+                break;
+            case csv_mode::data:
+            case csv_mode::subfields:
+            {
+                switch (options_.mapping_kind())
+                {
+                    case csv_mapping_kind::n_rows:
+                        more_ = visitor_->end_array(*this, ec);
+                        break;
+                    case csv_mapping_kind::n_objects:
+                        more_ = visitor_->end_object(*this, ec);
+                        break;
+                    case csv_mapping_kind::m_columns:
+                        more_ = visitor_->end_array(*this, ec);
+                        break;
+                }
+                break;
+            }
+            default:
+                break;
+        }
+        column_index_ = 0;
+    }
+
+    void trim_string_buffer(bool trim_leading, bool trim_trailing)
+    {
+        std::size_t start = 0;
+        std::size_t length = buffer_.length();
+        if (trim_leading)
+        {
+            bool done = false;
+            while (!done && start < buffer_.length())
+            {
+                if ((buffer_[start] < 256) && std::isspace(buffer_[start]))
+                {
+                    ++start;
+                }
+                else
+                {
+                    done = true;
+                }
+            }
+        }
+        if (trim_trailing)
+        {
+            bool done = false;
+            while (!done && length > 0)
+            {
+                if ((buffer_[length-1] < 256) && std::isspace(buffer_[length-1]))
+                {
+                    --length;
+                }
+                else
+                {
+                    done = true;
+                }
+            }
+        }
+        if (start != 0 || length != buffer_.size())
+        {
+            buffer_ = buffer_.substr(start,length-start);
+        }
+    }
+
+    /*
+        end_array, begin_array, xxx_value (end_value)
+    */
+    void end_unquoted_string_value(std::error_code& ec) 
+    {
+        switch (stack_.back())
+        {
+            case csv_mode::data:
+            case csv_mode::subfields:
+                switch (options_.mapping_kind())
+                {
+                case csv_mapping_kind::n_rows:
+                    if (options_.unquoted_empty_value_is_null() && buffer_.length() == 0)
+                    {
+                        more_ = visitor_->null_value(semantic_tag::none, *this, ec);
+                    }
+                    else
+                    {
+                        end_value(options_.infer_types(), ec);
+                    }
+                    break;
+                case csv_mapping_kind::n_objects:
+                    if (!(options_.ignore_empty_values() && buffer_.empty()))
+                    {
+                        if (column_index_ < column_names_.size() + offset_)
+                        {
+                            if (options_.unquoted_empty_value_is_null() && buffer_.length() == 0)
+                            {
+                                more_ = visitor_->null_value(semantic_tag::none, *this, ec);
+                            }
+                            else
+                            {
+                                end_value(options_.infer_types(), ec);
+                            }
+                        }
+                        else if (level_ > 0)
+                        {
+                            if (options_.unquoted_empty_value_is_null() && buffer_.length() == 0)
+                            {
+                                more_ = visitor_->null_value(semantic_tag::none, *this, ec);
+                            }
+                            else
+                            {
+                                end_value(options_.infer_types(), ec);
+                            }
+                        }
+                    }
+                    break;
+                case csv_mapping_kind::m_columns:
+                    if (!(options_.ignore_empty_values() && buffer_.empty()))
+                    {
+                        end_value(options_.infer_types(), ec);
+                    }
+                    else
+                    {
+                        m_columns_filter_.skip_column();
+                    }
+                    break;
+                }
+                break;
+            default:
+                break;
+        }
+    }
+
+    void end_quoted_string_value(std::error_code& ec) 
+    {
+        switch (stack_.back())
+        {
+            case csv_mode::data:
+            case csv_mode::subfields:
+                if (options_.trim_leading_inside_quotes() || options_.trim_trailing_inside_quotes())
+                {
+                    trim_string_buffer(options_.trim_leading_inside_quotes(),options_.trim_trailing_inside_quotes());
+                }
+                switch (options_.mapping_kind())
+                {
+                case csv_mapping_kind::n_rows:
+                    end_value(false, ec);
+                    break;
+                case csv_mapping_kind::n_objects:
+                    if (!(options_.ignore_empty_values() && buffer_.empty()))
+                    {
+                        if (column_index_ < column_names_.size() + offset_)
+                        {
+                            if (options_.unquoted_empty_value_is_null() && buffer_.length() == 0)
+                            {
+                                more_ = visitor_->null_value(semantic_tag::none, *this, ec);
+                            }
+                            else 
+                            {
+                                end_value(false, ec);
+                            }
+                        }
+                        else if (level_ > 0)
+                        {
+                            if (options_.unquoted_empty_value_is_null() && buffer_.length() == 0)
+                            {
+                                more_ = visitor_->null_value(semantic_tag::none, *this, ec);
+                            }
+                            else
+                            {
+                                end_value(false, ec);
+                            }
+                        }
+                    }
+                    break;
+                case csv_mapping_kind::m_columns:
+                    if (!(options_.ignore_empty_values() && buffer_.empty()))
+                    {
+                        end_value(false, ec);
+                    }
+                    else
+                    {
+                        m_columns_filter_.skip_column();
+                    }
+                    break;
+                }
+                break;
+            default:
+                break;
+        }
+    }
+
+    void end_value(bool infer_types, std::error_code&  ec)
+    {
+        auto it = std::find_if(string_double_map_.begin(), string_double_map_.end(), string_maps_to_double{ buffer_ });
+        if (it != string_double_map_.end())
+        {
+            more_ = visitor_->double_value(it->second, semantic_tag::none, *this, ec);
+        }
+        else if (column_index_ < column_types_.size() + offset_)
+        {
+            if (column_types_[column_index_ - offset_].col_type == csv_column_type::repeat_t)
+            {
+                offset_ = offset_ + column_types_[column_index_ - offset_].rep_count;
+                if (column_index_ - offset_ + 1 < column_types_.size())
+                {
+                    if (column_index_ == offset_ || level_ > column_types_[column_index_-offset_].level)
+                    {
+                        more_ = visitor_->end_array(*this, ec);
+                    }
+                    level_ = column_index_ == offset_ ? 0 : column_types_[column_index_ - offset_].level;
+                }
+            }
+            if (level_ < column_types_[column_index_ - offset_].level)
+            {
+                more_ = visitor_->begin_array(semantic_tag::none, *this, ec);
+                level_ = column_types_[column_index_ - offset_].level;
+            }
+            else if (level_ > column_types_[column_index_ - offset_].level)
+            {
+                more_ = visitor_->end_array(*this, ec);
+                level_ = column_types_[column_index_ - offset_].level;
+            }
+            switch (column_types_[column_index_ - offset_].col_type)
+            {
+                case csv_column_type::integer_t:
+                    {
+                        std::basic_istringstream<CharT,std::char_traits<CharT>,char_allocator_type> iss{buffer_};
+                        int64_t val;
+                        iss >> val;
+                        if (!iss.fail())
+                        {
+                            more_ = visitor_->int64_value(val, semantic_tag::none, *this, ec);
+                        }
+                        else
+                        {
+                            if (column_index_ - offset_ < column_defaults_.size() && column_defaults_[column_index_ - offset_].length() > 0)
+                            {
+                                basic_json_parser<CharT,temp_allocator_type> parser(alloc_);
+                                parser.update(column_defaults_[column_index_ - offset_].data(),column_defaults_[column_index_ - offset_].length());
+                                parser.parse_some(*visitor_);
+                                parser.finish_parse(*visitor_);
+                            }
+                            else
+                            {
+                                more_ = visitor_->null_value(semantic_tag::none, *this, ec);
+                            }
+                        }
+                    }
+                    break;
+                case csv_column_type::float_t:
+                    {
+                        if (options_.lossless_number())
+                        {
+                            more_ = visitor_->string_value(buffer_,semantic_tag::bigdec, *this, ec);
+                        }
+                        else
+                        {
+                            std::basic_istringstream<CharT, std::char_traits<CharT>, char_allocator_type> iss{ buffer_ };
+                            double val;
+                            iss >> val;
+                            if (!iss.fail())
+                            {
+                                more_ = visitor_->double_value(val, semantic_tag::none, *this, ec);
+                            }
+                            else
+                            {
+                                if (column_index_ - offset_ < column_defaults_.size() && column_defaults_[column_index_ - offset_].length() > 0)
+                                {
+                                    basic_json_parser<CharT,temp_allocator_type> parser(alloc_);
+                                    parser.update(column_defaults_[column_index_ - offset_].data(),column_defaults_[column_index_ - offset_].length());
+                                    parser.parse_some(*visitor_);
+                                    parser.finish_parse(*visitor_);
+                                }
+                                else
+                                {
+                                    more_ = visitor_->null_value(semantic_tag::none, *this, ec);
+                                }
+                            }
+                        }
+                    }
+                    break;
+                case csv_column_type::boolean_t:
+                    {
+                        if (buffer_.length() == 1 && buffer_[0] == '0')
+                        {
+                            more_ = visitor_->bool_value(false, semantic_tag::none, *this, ec);
+                        }
+                        else if (buffer_.length() == 1 && buffer_[0] == '1')
+                        {
+                            more_ = visitor_->bool_value(true, semantic_tag::none, *this, ec);
+                        }
+                        else if (buffer_.length() == 5 && ((buffer_[0] == 'f' || buffer_[0] == 'F') && (buffer_[1] == 'a' || buffer_[1] == 'A') && (buffer_[2] == 'l' || buffer_[2] == 'L') && (buffer_[3] == 's' || buffer_[3] == 'S') && (buffer_[4] == 'e' || buffer_[4] == 'E')))
+                        {
+                            more_ = visitor_->bool_value(false, semantic_tag::none, *this, ec);
+                        }
+                        else if (buffer_.length() == 4 && ((buffer_[0] == 't' || buffer_[0] == 'T') && (buffer_[1] == 'r' || buffer_[1] == 'R') && (buffer_[2] == 'u' || buffer_[2] == 'U') && (buffer_[3] == 'e' || buffer_[3] == 'E')))
+                        {
+                            more_ = visitor_->bool_value(true, semantic_tag::none, *this, ec);
+                        }
+                        else
+                        {
+                            if (column_index_ - offset_ < column_defaults_.size() && column_defaults_[column_index_ - offset_].length() > 0)
+                            {
+                                basic_json_parser<CharT,temp_allocator_type> parser(alloc_);
+                                parser.update(column_defaults_[column_index_ - offset_].data(),column_defaults_[column_index_ - offset_].length());
+                                parser.parse_some(*visitor_);
+                                parser.finish_parse(*visitor_);
+                            }
+                            else
+                            {
+                                more_ = visitor_->null_value(semantic_tag::none, *this, ec);
+                            }
+                        }
+                    }
+                    break;
+                default:
+                    if (buffer_.length() > 0)
+                    {
+                        more_ = visitor_->string_value(buffer_, semantic_tag::none, *this, ec);
+                    }
+                    else
+                    {
+                        if (column_index_ < column_defaults_.size() + offset_ && column_defaults_[column_index_ - offset_].length() > 0)
+                        {
+                            basic_json_parser<CharT,temp_allocator_type> parser(alloc_);
+                            parser.update(column_defaults_[column_index_ - offset_].data(),column_defaults_[column_index_ - offset_].length());
+                            parser.parse_some(*visitor_);
+                            parser.finish_parse(*visitor_);
+                        }
+                        else
+                        {
+                            more_ = visitor_->string_value(string_view_type(), semantic_tag::none, *this, ec);
+                        }
+                    }
+                    break;  
+            }
+        }
+        else
+        {
+            if (infer_types)
+            {
+                end_value_with_numeric_check(ec);
+            }
+            else
+            {
+                more_ = visitor_->string_value(buffer_, semantic_tag::none, *this, ec);
+            }
+        }
+    }
+
+    enum class numeric_check_state 
+    {
+        initial,
+        null,
+        boolean_true,
+        boolean_false,
+        minus,
+        zero,
+        integer,
+        fraction1,
+        fraction,
+        exp1,
+        exp,
+        not_a_number
+    };
+
+    /*
+        xxx_value 
+    */
+    void end_value_with_numeric_check(std::error_code& ec)
+    {
+        numeric_check_state state = numeric_check_state::initial;
+        bool is_negative = false;
+        int precision = 0;
+        uint8_t decimal_places = 0;
+
+        auto last = buffer_.end();
+
+        std::string buffer;
+        for (auto p = buffer_.begin(); state != numeric_check_state::not_a_number && p != last; ++p)
+        {
+            switch (state)
+            {
+                case numeric_check_state::initial:
+                {
+                    switch (*p)
+                    {
+                    case 'n':case 'N':
+                        if ((last-p) == 4 && (p[1] == 'u' || p[1] == 'U') && (p[2] == 'l' || p[2] == 'L') && (p[3] == 'l' || p[3] == 'L'))
+                        {
+                            state = numeric_check_state::null;
+                        }
+                        else
+                        {
+                            state = numeric_check_state::not_a_number;
+                        }
+                        break;
+                    case 't':case 'T':
+                        if ((last-p) == 4 && (p[1] == 'r' || p[1] == 'R') && (p[2] == 'u' || p[2] == 'U') && (p[3] == 'e' || p[3] == 'U'))
+                        {
+                            state = numeric_check_state::boolean_true;
+                        }
+                        else
+                        {
+                            state = numeric_check_state::not_a_number;
+                        }
+                        break;
+                    case 'f':case 'F':
+                        if ((last-p) == 5 && (p[1] == 'a' || p[1] == 'A') && (p[2] == 'l' || p[2] == 'L') && (p[3] == 's' || p[3] == 'S') && (p[4] == 'e' || p[4] == 'E'))
+                        {
+                            state = numeric_check_state::boolean_false;
+                        }
+                        else
+                        {
+                            state = numeric_check_state::not_a_number;
+                        }
+                        break;
+                    case '-':
+                        is_negative = true;
+                        buffer.push_back(*p);
+                        state = numeric_check_state::minus;
+                        break;
+                    case '0':
+                        ++precision;
+                        buffer.push_back(*p);
+                        state = numeric_check_state::zero;
+                        break;
+                    case '1':case '2':case '3':case '4':case '5':case '6':case '7':case '8':case '9':
+                        ++precision;
+                        buffer.push_back(*p);
+                        state = numeric_check_state::integer;
+                        break;
+                    default:
+                        state = numeric_check_state::not_a_number;
+                        break;
+                    }
+                    break;
+                }
+                case numeric_check_state::zero:
+                {
+                    switch (*p)
+                    {
+                    case '.':
+                        buffer.push_back(to_double_.get_decimal_point());
+                        state = numeric_check_state::fraction1;
+                        break;
+                    case 'e':case 'E':
+                        buffer.push_back(*p);
+                        state = numeric_check_state::exp1;
+                        break;
+                    default:
+                        state = numeric_check_state::not_a_number;
+                        break;
+                    }
+                    break;
+                }
+                case numeric_check_state::integer:
+                {
+                    switch (*p)
+                    {
+                    case '0':case '1':case '2':case '3':case '4':case '5':case '6':case '7':case '8':case '9':
+                        ++precision;
+                        buffer.push_back(*p);
+                        break;
+                    case '.':
+                        buffer.push_back(to_double_.get_decimal_point());
+                        state = numeric_check_state::fraction1;
+                        break;
+                    case 'e':case 'E':
+                        buffer.push_back(*p);
+                        state = numeric_check_state::exp1;
+                        break;
+                    default:
+                        state = numeric_check_state::not_a_number;
+                        break;
+                    }
+                    break;
+                }
+                case numeric_check_state::minus:
+                {
+                    switch (*p)
+                    {
+                    case '0':
+                        ++precision;
+                        buffer.push_back(*p);
+                        state = numeric_check_state::zero;
+                        break;
+                    case '1':case '2':case '3':case '4':case '5':case '6':case '7':case '8':case '9':
+                        ++precision;
+                        buffer.push_back(*p);
+                        state = numeric_check_state::integer;
+                        break;
+                    default:
+                        state = numeric_check_state::not_a_number;
+                        break;
+                    }
+                    break;
+                }
+                case numeric_check_state::fraction1:
+                {
+                    switch (*p)
+                    {
+                    case '0':case '1':case '2':case '3':case '4':case '5':case '6':case '7':case '8':case '9':
+                        ++precision;
+                        ++decimal_places;
+                        buffer.push_back(*p);
+                        state = numeric_check_state::fraction;
+                        break;
+                    default:
+                        state = numeric_check_state::not_a_number;
+                        break;
+                    }
+                    break;
+                }
+                case numeric_check_state::fraction:
+                {
+                    switch (*p)
+                    {
+                    case '0':case '1':case '2':case '3':case '4':case '5':case '6':case '7':case '8':case '9':
+                        ++precision;
+                        ++decimal_places;
+                        buffer.push_back(*p);
+                        break;
+                    case 'e':case 'E':
+                        buffer.push_back(*p);
+                        state = numeric_check_state::exp1;
+                        break;
+                    default:
+                        state = numeric_check_state::not_a_number;
+                        break;
+                    }
+                    break;
+                }
+                case numeric_check_state::exp1:
+                {
+                    switch (*p)
+                    {
+                    case '-':
+                        buffer.push_back(*p);
+                        break;
+                    case '+':
+                        break;
+                    case '0':case '1':case '2':case '3':case '4':case '5':case '6':case '7':case '8':case '9':
+                        state = numeric_check_state::exp;
+                        buffer.push_back(*p);
+                        break;
+                    default:
+                        state = numeric_check_state::not_a_number;
+                        break;
+                    }
+                    break;
+                }
+                case numeric_check_state::exp:
+                {
+                    switch (*p)
+                    {
+                    case '0':case '1':case '2':case '3':case '4':case '5':case '6':case '7':case '8':case '9':
+                        buffer.push_back(*p);
+                        break;
+                    default:
+                        state = numeric_check_state::not_a_number;
+                        break;
+                    }
+                    break;
+                }
+                default:
+                    break;
+            }
+        }
+
+        switch (state)
+        {
+            case numeric_check_state::null:
+                more_ = visitor_->null_value(semantic_tag::none, *this, ec);
+                break;
+            case numeric_check_state::boolean_true:
+                more_ = visitor_->bool_value(true, semantic_tag::none, *this, ec);
+                break;
+            case numeric_check_state::boolean_false:
+                more_ = visitor_->bool_value(false, semantic_tag::none, *this, ec);
+                break;
+            case numeric_check_state::zero:
+            case numeric_check_state::integer:
+            {
+                if (is_negative)
+                {
+                    int64_t val{ 0 };
+                    auto result = jsoncons::detail::to_integer_decimal(buffer_.data(), buffer_.length(), val);
+                    if (result)
+                    {
+                        more_ = visitor_->int64_value(val, semantic_tag::none, *this, ec);
+                    }
+                    else // Must be overflow
+                    {
+                        more_ = visitor_->string_value(buffer_, semantic_tag::bigint, *this, ec);
+                    }
+                }
+                else
+                {
+                    uint64_t val{ 0 };
+                    auto result = jsoncons::detail::to_integer_decimal(buffer_.data(), buffer_.length(), val);
+                    if (result)
+                    {
+                        more_ = visitor_->uint64_value(val, semantic_tag::none, *this, ec);
+                    }
+                    else if (result.ec == jsoncons::detail::to_integer_errc::overflow)
+                    {
+                        more_ = visitor_->string_value(buffer_, semantic_tag::bigint, *this, ec);
+                    }
+                    else
+                    {
+                        ec = result.ec;
+                        more_ = false;
+                        return;
+                    }
+                }
+                break;
+            }
+            case numeric_check_state::fraction:
+            case numeric_check_state::exp:
+            {
+                if (options_.lossless_number())
+                {
+                    more_ = visitor_->string_value(buffer_,semantic_tag::bigdec, *this, ec);
+                }
+                else
+                {
+                    double d = to_double_(buffer.c_str(), buffer.length());
+                    more_ = visitor_->double_value(d, semantic_tag::none, *this, ec);
+                }
+                break;
+            }
+            default:
+            {
+                more_ = visitor_->string_value(buffer_, semantic_tag::none, *this, ec);
+                break;
+            }
+        }
+    } 
+
+    void push_state(csv_parse_state state)
+    {
+        state_stack_.push_back(state);
+    }
+
+    csv_parse_state pop_state()
+    {
+        JSONCONS_ASSERT(!state_stack_.empty())
+        csv_parse_state state = state_stack_.back();
+        state_stack_.pop_back();
+        return state;
+    }
+};
+
+using csv_parser = basic_csv_parser<char>;
+using wcsv_parser = basic_csv_parser<wchar_t>;
+
+}}
+
+#endif
+