diff --git a/source/cli/meojson/json.hpp b/source/cli/meojson/json.hpp
index aed9618..571d575 100644
--- a/source/cli/meojson/json.hpp
+++ b/source/cli/meojson/json.hpp
@@ -306,6 +306,7 @@ class basic_array
 
     void clear() noexcept;
     bool erase(size_t pos);
+    bool erase(iterator iter);
 
     iterator begin() noexcept;
     iterator end() noexcept;
@@ -419,6 +420,7 @@ class basic_object
 
     void clear() noexcept;
     bool erase(const string_t& key);
+    bool erase(iterator iter);
 
     iterator begin() noexcept;
     iterator end() noexcept;
@@ -563,8 +565,14 @@ namespace literals
 template <typename string_t = default_string_t>
 const basic_value<string_t> invalid_value();
 
-template <bool loose, typename any_t, typename string_t = default_string_t>
-basic_value<string_t> serialize(any_t&& arg);
+namespace _serialization_helper
+{
+    template <bool loose, typename string_t>
+    struct string_converter;
+}
+template <bool loose, typename any_t, typename string_t = default_string_t,
+          typename string_converter_t = _serialization_helper::string_converter<loose, string_t>>
+basic_value<string_t> serialize(any_t&& arg, string_converter_t&& string_converter = {});
 
 // ******************************
 // *      basic_value impl      *
@@ -1367,7 +1375,13 @@ MEOJSON_INLINE void basic_array<string_t>::clear() noexcept
 template <typename string_t>
 MEOJSON_INLINE bool basic_array<string_t>::erase(size_t pos)
 {
-    return _array_data.erase(pos) != _array_data.end();
+    return erase(_array_data.begin() + pos);
+}
+
+template <typename string_t>
+MEOJSON_INLINE bool basic_array<string_t>::erase(iterator iter)
+{
+    return _array_data.erase(iter) != _array_data.end();
 }
 
 template <typename string_t>
@@ -1693,6 +1707,12 @@ MEOJSON_INLINE bool basic_object<string_t>::erase(const string_t& key)
     return _object_data.erase(key) > 0 ? true : false;
 }
 
+template <typename string_t>
+MEOJSON_INLINE bool basic_object<string_t>::erase(iterator iter)
+{
+    return _object_data.erase(iter) != _object_data.end();
+}
+
 template <typename string_t>
 template <typename... args_t>
 MEOJSON_INLINE decltype(auto) basic_object<string_t>::emplace(args_t&&... args)
@@ -2514,11 +2534,13 @@ MEOJSON_INLINE const basic_value<string_t> invalid_value()
 
 namespace _serialization_helper
 {
-    template <typename T>
+    template <typename char_t, typename T>
     class has_output_operator
     {
+        using ostringstream_t = std::basic_ostringstream<char_t, std::char_traits<char_t>, std::allocator<char_t>>;
+
         template <typename U>
-        static auto test(int) -> decltype(std::declval<std::ostream&>() << std::declval<U>(), std::true_type());
+        static auto test(int) -> decltype(std::declval<ostringstream_t&>() << std::declval<U>(), std::true_type());
 
         template <typename U>
         static std::false_type test(...);
@@ -2549,44 +2571,40 @@ namespace _serialization_helper
     template <typename T>
     constexpr bool is_sequence_container<T> = is_container<T> && !is_associative_container<T>;
 
-    template <typename input_t, typename string_t>
-    MEOJSON_INLINE string_t to_stream_string(input_t&& arg)
-    {
-        if constexpr (has_output_operator<input_t>::value) {
-            using char_t = typename string_t::value_type;
-            using stringstream_t = std::basic_stringstream<char_t, std::char_traits<char_t>, std::allocator<char_t>>;
-
-            stringstream_t ss;
-            ss << std::forward<input_t>(arg);
-            return std::move(ss).str();
-        }
-        else {
-            static_assert(!sizeof(input_t), "Unable to convert type to string, there is no operator <<.");
-        }
-    }
-
-    template <bool loose, typename input_t, typename string_t>
-    MEOJSON_INLINE string_t to_string(input_t&& arg)
+    template <bool loose, typename string_t>
+    struct string_converter
     {
-        if constexpr (std::is_constructible_v<string_t, input_t>) {
-            return arg;
-        }
-        else if constexpr (loose) {
-            return to_stream_string<input_t, string_t>(std::forward<input_t>(arg));
-        }
-        else {
-            static_assert(!sizeof(input_t), "Unable to convert type to string.");
+        using char_t = typename string_t::value_type;
+        using ostringstream_t = std::basic_ostringstream<char_t, std::char_traits<char_t>, std::allocator<char_t>>;
+
+        template <typename input_t>
+        string_t operator()(input_t&& arg) const
+        {
+            if constexpr (std::is_constructible_v<string_t, input_t>) {
+                return string_t(std::forward<input_t>(arg));
+            }
+            else if constexpr (!loose) {
+                static_assert(!sizeof(input_t), "Unable to convert type to string.");
+            }
+            else if constexpr (has_output_operator<char_t, input_t>::value) {
+                ostringstream_t os;
+                os << std::forward<input_t>(arg);
+                return std::move(os).str();
+            }
+            else {
+                return serialize<loose, input_t, string_t>(std::forward<input_t>(arg), *this).dumps();
+            }
         }
-    }
+    };
 }
 
-template <bool loose, typename any_t, typename string_t>
-MEOJSON_INLINE basic_value<string_t> serialize(any_t&& arg)
+template <bool loose, typename any_t, typename string_t, typename string_converter_t>
+MEOJSON_INLINE basic_value<string_t> serialize(any_t&& arg, string_converter_t&& string_converter)
 {
     using namespace _serialization_helper;
 
     if constexpr (std::is_constructible_v<basic_value<string_t>, any_t>) {
-        return arg;
+        return basic_value<string_t>(std::forward<any_t>(arg));
     }
     else if constexpr (std::is_constructible_v<basic_array<string_t>, any_t>) {
         return basic_array<string_t>(std::forward<any_t>(arg));
@@ -2599,7 +2617,7 @@ MEOJSON_INLINE basic_value<string_t> serialize(any_t&& arg)
         for (auto&& val : arg) {
             using value_t = decltype(val);
 
-            result.emplace(serialize<loose, value_t, string_t>(std::forward<value_t>(val)));
+            result.emplace(serialize<loose, value_t, string_t>(std::forward<value_t>(val), string_converter));
         }
         return result;
     }
@@ -2609,13 +2627,13 @@ MEOJSON_INLINE basic_value<string_t> serialize(any_t&& arg)
             using key_t = decltype(key);
             using value_t = decltype(val);
 
-            result.emplace(to_string<loose, key_t, string_t>(std::forward<key_t>(key)),
-                           serialize<loose, value_t, string_t>(std::forward<value_t>(val)));
+            result.emplace(string_converter(std::forward<key_t>(key)),
+                           serialize<loose, value_t, string_t>(std::forward<value_t>(val), string_converter));
         }
         return result;
     }
     else {
-        return to_string<loose, any_t, string_t>(std::forward<any_t>(arg));
+        return string_converter(std::forward<any_t>(arg));
     }
 }
 
diff --git a/source/cli/meojson/json5.hpp b/source/cli/meojson/json5.hpp
new file mode 100644
index 0000000..d6ca3f5
--- /dev/null
+++ b/source/cli/meojson/json5.hpp
@@ -0,0 +1,1721 @@
+#pragma once
+
+#include <cctype>
+#include <clocale>
+#include <cmath>
+#include <iomanip>
+#include <regex>
+#include <sstream>
+#include <stack>
+
+#include "json.hpp"
+
+namespace json
+{
+    // *************************
+    // *         declare       *
+    // *************************
+
+    template<typename StringT>
+    class parser5
+    {
+    private:
+        using StringIterT = typename StringT::const_iterator;
+        using u8char = uint64_t;
+
+        /* exceptions */
+    public:
+        class exception : public json::exception
+        {
+        public:
+            exception() = default;
+            exception(const std::string& type, const std::string& msg,
+                      const std::string& detail)
+            {
+                std::stringstream ss;
+                ss << "JSON5: [" << type << "] " << msg << '\n';
+                ss << detail << std::endl;
+                _what = ss.str();
+            }
+            exception(const exception&) = default;
+            exception& operator=(const exception&) = default;
+            exception(exception&&) = default;
+            exception& operator=(exception&&) = default;
+
+            virtual ~exception() noexcept = default;
+        };
+
+        class InvalidChar : public exception
+        {
+        public:
+            InvalidChar(u8char ch = 0, const std::string& detail = "")
+                : exception("Invalid Char",
+                            "Unexpected token \'" + StringFromCharCode(ch) + "\'",
+                            detail)
+            {}
+        };
+
+        class InvalidIdentifier : public exception
+        {
+        public:
+            InvalidIdentifier(const std::string& msg = "",
+                              const std::string& detail = "")
+                : exception("Invalid Identifier", msg, detail)
+            {}
+        };
+
+        class InvalidEOF : public exception
+        {
+        public:
+            InvalidEOF(const std::string& msg = "", const std::string& detail = "")
+                : exception("Invalid EOF", msg, detail)
+            {}
+        };
+
+    public:
+        std::string exceptionDetailInfo()
+        {
+            size_t start_point = _col;
+            auto len = _print_len;
+            auto current_line = _line_begin_cur;
+            std::stringstream ss;
+            ss << "at line " << _line << ", column " << _col + 1 << '\n';
+
+            while (read() != '\n' && _cur != _end && (_col - start_point) < 5)
+                ;
+            ss << std::string(current_line, _cur) << '\n';
+            ss << std::setw(len) << '^' << '\n';
+            return ss.str();
+        }
+
+        /* helper class and type */
+    private:
+        class unicode
+        {
+        public:
+            static const std::wregex space_separator;
+            static const std::wregex id_start;
+            static const std::wregex id_continue;
+
+            static bool isSpaceSeparator(u8char ch);
+            static bool isIdStartChar(u8char ch);
+            static bool isIdContinueChar(u8char ch);
+            static bool isDigit(u8char ch);
+            static bool isHexDigit(u8char ch);
+        };
+
+        enum class LexState
+        {
+            default_ = 0,
+            comment,
+            multiLineComment,
+            multiLineCommentAsterisk,
+            singleLineComment,
+            value,
+            identifierNameStartEscape,
+            identifierName,
+            identifierNameEscape,
+            sign,
+            zero,
+            decimalInteger,
+            decimalPointLeading,
+            decimalPoint,
+            decimalFraction,
+            decimalExponent,
+            decimalExponentSign,
+            decimalExponentInteger,
+            hexadecimal,
+            hexadecimalInteger,
+            string,
+            start,
+            beforePropertyName,
+            afterPropertyName,
+            beforePropertyValue,
+            afterPropertyValue,
+            beforeArrayValue,
+            afterArrayValue,
+            end
+        };
+
+        enum class ParseState
+        {
+            start = 21,
+            beforePropertyName,
+            afterPropertyName,
+            beforePropertyValue,
+            afterPropertyValue,
+            beforeArrayValue,
+            afterArrayValue,
+            end
+        };
+
+        enum class TokenType
+        {
+            punctuator = 0,
+            identifier,
+            null,
+            boolean,
+            numeric,
+            string,
+            eof,
+        };
+
+        struct Token
+        {
+            TokenType type;
+            value _value;
+            size_t col = 0;
+            size_t line = 0;
+        };
+
+        /* constrators and callers */
+    public:
+        ~parser5() noexcept = default;
+        static std::optional<value> parse(const StringT& content, std::string* error = nullptr);
+
+    private:
+        parser5(const StringIterT& cbegin,
+                const StringIterT& cend) noexcept
+            : _cur(cbegin), _end(cend), _line_begin_cur(cbegin)
+        {}
+        std::optional<value> parse();
+
+    private:
+        /* utf-8 reader */
+        static u8char peek(StringIterT& begin,
+                           const StringIterT& end,
+                           size_t* len = nullptr);
+        static u8char peek(const std::string& str);
+        typename parser5<StringT>::u8char read();
+        static std::string StringFromCharCode(u8char code);
+        /* escape and format */
+        void literal(const std::string& s);
+        std::optional<u8char> escape();
+        u8char hexEscape();
+        u8char unicodeEscape();
+        /* lex, parse, token */
+        Token lex();
+        Token newToken(TokenType type, value value);
+
+        std::optional<Token> lex_default();
+        std::optional<Token> lex_comment();
+        std::optional<Token> lex_multiLineComment();
+        std::optional<Token> lex_multiLineCommentAsterisk();
+        std::optional<Token> lex_singleLineComment();
+        std::optional<Token> lex_value();
+        std::optional<Token> lex_identifierNameStartEscape();
+        std::optional<Token> lex_identifierName();
+        std::optional<Token> lex_identifierNameEscape();
+        std::optional<Token> lex_sign();
+        std::optional<Token> lex_zero();
+        std::optional<Token> lex_decimalInteger();
+        std::optional<Token> lex_decimalPointLeading();
+        std::optional<Token> lex_decimalPoint();
+        std::optional<Token> lex_decimalFraction();
+        std::optional<Token> lex_decimalExponent();
+        std::optional<Token> lex_decimalExponentSign();
+        std::optional<Token> lex_decimalExponentInteger();
+        std::optional<Token> lex_hexadecimal();
+        std::optional<Token> lex_hexdecimalInteger();
+        std::optional<Token> lex_string();
+        std::optional<Token> lex_start();
+        std::optional<Token> lex_beforePropertyName();
+        std::optional<Token> lex_afterPropertyName();
+        std::optional<Token> lex_beforePropertyValue();
+        std::optional<Token> lex_afterPropertyValue();
+        std::optional<Token> lex_beforeArrayValue();
+        std::optional<Token> lex_afterArrayValue();
+        std::optional<Token> lex_end();
+
+        std::optional<Token> lexStates(LexState state);
+
+        void parse_start();
+        void parse_beforePropertyName();
+        void parse_afterPropertyName();
+        void parse_beforePropertyValue();
+        void parse_beforeArrayValue();
+        void parse_afterPropertyValue();
+        void parse_afterArrayValue();
+        void parse_end();
+
+        void parseStates(ParseState state);
+
+        /* stack operation */
+        void push();
+        void pop();
+
+    private:
+        StringIterT _cur, _end;
+        StringIterT _line_begin_cur;
+        size_t _line = 1, _col = 0, _print_len = 0;
+        ParseState _parse_state = ParseState::start;
+        std::stack<value*> _stack;
+        std::optional<Token> _token;
+        std::string _key;
+        std::optional<value> _root;
+
+        LexState _lex_state = LexState::default_;
+        std::string _buffer;
+        bool _double_quote = false;
+        int64_t _sign = 1;
+        u8char _current_char = 0;
+    };
+
+    // *************************
+    // *    implementation     *
+    // *************************
+
+    /* parser5<StringT>::unicode */
+    template<typename StringT>
+    MEOJSON_INLINE const std::wregex parser5<StringT>::unicode::space_separator =
+        std::wregex(LR"([\u1680\u2000-\u200A\u202F\u205F\u3000])");
+
+    template<typename StringT>
+    MEOJSON_INLINE const std::wregex parser5<StringT>::unicode::id_start = std::wregex(
+        LR"([\xAA\xB5\xBA\xC0-\xD6\xD8-\xF6\xF8-\u02C1\u02C6-\u02D1\u02E0-)"
+        LR"(\u02E4\u02EC\u02EE\u0370-\u0374\u0376\u0377\u037A-)"
+        LR"(\u037D\u037F\u0386\u0388-\u038A\u038C\u038E-\u03A1\u03A3-\u03F5\u03F7-)"
+        LR"(\u0481\u048A-\u052F\u0531-\u0556\u0559\u0561-\u0587\u05D0-\u05EA\u05F0-)"
+        LR"(\u05F2\u0620-\u064A\u066E\u066F\u0671-)"
+        LR"(\u06D3\u06D5\u06E5\u06E6\u06EE\u06EF\u06FA-\u06FC\u06FF\u0710\u0712-)"
+        LR"(\u072F\u074D-\u07A5\u07B1\u07CA-\u07EA\u07F4\u07F5\u07FA\u0800-)"
+        LR"(\u0815\u081A\u0824\u0828\u0840-\u0858\u0860-\u086A\u08A0-\u08B4\u08B6-)"
+        LR"(\u08BD\u0904-\u0939\u093D\u0950\u0958-\u0961\u0971-\u0980\u0985-)"
+        LR"(\u098C\u098F\u0990\u0993-\u09A8\u09AA-\u09B0\u09B2\u09B6-)"
+        LR"(\u09B9\u09BD\u09CE\u09DC\u09DD\u09DF-\u09E1\u09F0\u09F1\u09FC\u0A05-)"
+        LR"(\u0A0A\u0A0F\u0A10\u0A13-\u0A28\u0A2A-)"
+        LR"(\u0A30\u0A32\u0A33\u0A35\u0A36\u0A38\u0A39\u0A59-\u0A5C\u0A5E\u0A72-)"
+        LR"(\u0A74\u0A85-\u0A8D\u0A8F-\u0A91\u0A93-\u0AA8\u0AAA-)"
+        LR"(\u0AB0\u0AB2\u0AB3\u0AB5-\u0AB9\u0ABD\u0AD0\u0AE0\u0AE1\u0AF9\u0B05-)"
+        LR"(\u0B0C\u0B0F\u0B10\u0B13-\u0B28\u0B2A-\u0B30\u0B32\u0B33\u0B35-)"
+        LR"(\u0B39\u0B3D\u0B5C\u0B5D\u0B5F-\u0B61\u0B71\u0B83\u0B85-\u0B8A\u0B8E-)"
+        LR"(\u0B90\u0B92-\u0B95\u0B99\u0B9A\u0B9C\u0B9E\u0B9F\u0BA3\u0BA4\u0BA8-)"
+        LR"(\u0BAA\u0BAE-\u0BB9\u0BD0\u0C05-\u0C0C\u0C0E-\u0C10\u0C12-\u0C28\u0C2A-)"
+        LR"(\u0C39\u0C3D\u0C58-\u0C5A\u0C60\u0C61\u0C80\u0C85-\u0C8C\u0C8E-)"
+        LR"(\u0C90\u0C92-\u0CA8\u0CAA-\u0CB3\u0CB5-)"
+        LR"(\u0CB9\u0CBD\u0CDE\u0CE0\u0CE1\u0CF1\u0CF2\u0D05-\u0D0C\u0D0E-)"
+        LR"(\u0D10\u0D12-\u0D3A\u0D3D\u0D4E\u0D54-\u0D56\u0D5F-\u0D61\u0D7A-)"
+        LR"(\u0D7F\u0D85-\u0D96\u0D9A-\u0DB1\u0DB3-\u0DBB\u0DBD\u0DC0-\u0DC6\u0E01-)"
+        LR"(\u0E30\u0E32\u0E33\u0E40-)"
+        LR"(\u0E46\u0E81\u0E82\u0E84\u0E87\u0E88\u0E8A\u0E8D\u0E94-\u0E97\u0E99-)"
+        LR"(\u0E9F\u0EA1-\u0EA3\u0EA5\u0EA7\u0EAA\u0EAB\u0EAD-)"
+        LR"(\u0EB0\u0EB2\u0EB3\u0EBD\u0EC0-\u0EC4\u0EC6\u0EDC-\u0EDF\u0F00\u0F40-)"
+        LR"(\u0F47\u0F49-\u0F6C\u0F88-\u0F8C\u1000-\u102A\u103F\u1050-\u1055\u105A-)"
+        LR"(\u105D\u1061\u1065\u1066\u106E-\u1070\u1075-\u1081\u108E\u10A0-)"
+        LR"(\u10C5\u10C7\u10CD\u10D0-\u10FA\u10FC-\u1248\u124A-\u124D\u1250-)"
+        LR"(\u1256\u1258\u125A-\u125D\u1260-\u1288\u128A-\u128D\u1290-\u12B0\u12B2-)"
+        LR"(\u12B5\u12B8-\u12BE\u12C0\u12C2-\u12C5\u12C8-\u12D6\u12D8-\u1310\u1312-)"
+        LR"(\u1315\u1318-\u135A\u1380-\u138F\u13A0-\u13F5\u13F8-\u13FD\u1401-)"
+        LR"(\u166C\u166F-\u167F\u1681-\u169A\u16A0-\u16EA\u16EE-\u16F8\u1700-)"
+        LR"(\u170C\u170E-\u1711\u1720-\u1731\u1740-\u1751\u1760-\u176C\u176E-)"
+        LR"(\u1770\u1780-\u17B3\u17D7\u17DC\u1820-\u1877\u1880-\u1884\u1887-)"
+        LR"(\u18A8\u18AA\u18B0-\u18F5\u1900-\u191E\u1950-\u196D\u1970-\u1974\u1980-)"
+        LR"(\u19AB\u19B0-\u19C9\u1A00-\u1A16\u1A20-\u1A54\u1AA7\u1B05-\u1B33\u1B45-)"
+        LR"(\u1B4B\u1B83-\u1BA0\u1BAE\u1BAF\u1BBA-\u1BE5\u1C00-\u1C23\u1C4D-)"
+        LR"(\u1C4F\u1C5A-\u1C7D\u1C80-\u1C88\u1CE9-\u1CEC\u1CEE-)"
+        LR"(\u1CF1\u1CF5\u1CF6\u1D00-\u1DBF\u1E00-\u1F15\u1F18-\u1F1D\u1F20-)"
+        LR"(\u1F45\u1F48-\u1F4D\u1F50-\u1F57\u1F59\u1F5B\u1F5D\u1F5F-\u1F7D\u1F80-)"
+        LR"(\u1FB4\u1FB6-\u1FBC\u1FBE\u1FC2-\u1FC4\u1FC6-\u1FCC\u1FD0-\u1FD3\u1FD6-)"
+        LR"(\u1FDB\u1FE0-\u1FEC\u1FF2-\u1FF4\u1FF6-\u1FFC\u2071\u207F\u2090-)"
+        LR"(\u209C\u2102\u2107\u210A-\u2113\u2115\u2119-)"
+        LR"(\u211D\u2124\u2126\u2128\u212A-\u212D\u212F-\u2139\u213C-\u213F\u2145-)"
+        LR"(\u2149\u214E\u2160-\u2188\u2C00-\u2C2E\u2C30-\u2C5E\u2C60-\u2CE4\u2CEB-)"
+        LR"(\u2CEE\u2CF2\u2CF3\u2D00-\u2D25\u2D27\u2D2D\u2D30-\u2D67\u2D6F\u2D80-)"
+        LR"(\u2D96\u2DA0-\u2DA6\u2DA8-\u2DAE\u2DB0-\u2DB6\u2DB8-\u2DBE\u2DC0-)"
+        LR"(\u2DC6\u2DC8-\u2DCE\u2DD0-\u2DD6\u2DD8-\u2DDE\u2E2F\u3005-\u3007\u3021-)"
+        LR"(\u3029\u3031-\u3035\u3038-\u303C\u3041-\u3096\u309D-\u309F\u30A1-)"
+        LR"(\u30FA\u30FC-\u30FF\u3105-\u312E\u3131-\u318E\u31A0-\u31BA\u31F0-)"
+        LR"(\u31FF\u3400-\u4DB5\u4E00-\u9FEA\uA000-\uA48C\uA4D0-\uA4FD\uA500-)"
+        LR"(\uA60C\uA610-\uA61F\uA62A\uA62B\uA640-\uA66E\uA67F-\uA69D\uA6A0-)"
+        LR"(\uA6EF\uA717-\uA71F\uA722-\uA788\uA78B-\uA7AE\uA7B0-\uA7B7\uA7F7-)"
+        LR"(\uA801\uA803-\uA805\uA807-\uA80A\uA80C-\uA822\uA840-\uA873\uA882-)"
+        LR"(\uA8B3\uA8F2-\uA8F7\uA8FB\uA8FD\uA90A-\uA925\uA930-\uA946\uA960-)"
+        LR"(\uA97C\uA984-\uA9B2\uA9CF\uA9E0-\uA9E4\uA9E6-\uA9EF\uA9FA-\uA9FE\uAA00-)"
+        LR"(\uAA28\uAA40-\uAA42\uAA44-\uAA4B\uAA60-\uAA76\uAA7A\uAA7E-)"
+        LR"(\uAAAF\uAAB1\uAAB5\uAAB6\uAAB9-\uAABD\uAAC0\uAAC2\uAADB-\uAADD\uAAE0-)"
+        LR"(\uAAEA\uAAF2-\uAAF4\uAB01-\uAB06\uAB09-\uAB0E\uAB11-\uAB16\uAB20-)"
+        LR"(\uAB26\uAB28-\uAB2E\uAB30-\uAB5A\uAB5C-\uAB65\uAB70-\uABE2\uAC00-)"
+        LR"(\uD7A3\uD7B0-\uD7C6\uD7CB-\uD7FB\uF900-\uFA6D\uFA70-\uFAD9\uFB00-)"
+        LR"(\uFB06\uFB13-\uFB17\uFB1D\uFB1F-\uFB28\uFB2A-\uFB36\uFB38-)"
+        LR"(\uFB3C\uFB3E\uFB40\uFB41\uFB43\uFB44\uFB46-\uFBB1\uFBD3-\uFD3D\uFD50-)"
+        LR"(\uFD8F\uFD92-\uFDC7\uFDF0-\uFDFB\uFE70-\uFE74\uFE76-\uFEFC\uFF21-)"
+        LR"(\uFF3A\uFF41-\uFF5A\uFF66-\uFFBE\uFFC2-\uFFC7\uFFCA-\uFFCF\uFFD2-)"
+        LR"(\uFFD7\uFFDA-\uFFDC]|\uD800[\uDC00-\uDC0B\uDC0D-\uDC26\uDC28-)"
+        LR"(\uDC3A\uDC3C\uDC3D\uDC3F-\uDC4D\uDC50-\uDC5D\uDC80-\uDCFA\uDD40-)"
+        LR"(\uDD74\uDE80-\uDE9C\uDEA0-\uDED0\uDF00-\uDF1F\uDF2D-\uDF4A\uDF50-)"
+        LR"(\uDF75\uDF80-\uDF9D\uDFA0-\uDFC3\uDFC8-\uDFCF\uDFD1-\uDFD5]|\uD801[\uDC00-)"
+        LR"(\uDC9D\uDCB0-\uDCD3\uDCD8-\uDCFB\uDD00-\uDD27\uDD30-\uDD63\uDE00-)"
+        LR"(\uDF36\uDF40-\uDF55\uDF60-\uDF67]|\uD802[\uDC00-\uDC05\uDC08\uDC0A-)"
+        LR"(\uDC35\uDC37\uDC38\uDC3C\uDC3F-\uDC55\uDC60-\uDC76\uDC80-\uDC9E\uDCE0-)"
+        LR"(\uDCF2\uDCF4\uDCF5\uDD00-\uDD15\uDD20-\uDD39\uDD80-)"
+        LR"(\uDDB7\uDDBE\uDDBF\uDE00\uDE10-\uDE13\uDE15-\uDE17\uDE19-\uDE33\uDE60-)"
+        LR"(\uDE7C\uDE80-\uDE9C\uDEC0-\uDEC7\uDEC9-\uDEE4\uDF00-\uDF35\uDF40-)"
+        LR"(\uDF55\uDF60-\uDF72\uDF80-\uDF91]|\uD803[\uDC00-\uDC48\uDC80-\uDCB2\uDCC0-)"
+        LR"(\uDCF2]|\uD804[\uDC03-\uDC37\uDC83-\uDCAF\uDCD0-\uDCE8\uDD03-\uDD26\uDD50-)"
+        LR"(\uDD72\uDD76\uDD83-\uDDB2\uDDC1-\uDDC4\uDDDA\uDDDC\uDE00-\uDE11\uDE13-)"
+        LR"(\uDE2B\uDE80-\uDE86\uDE88\uDE8A-\uDE8D\uDE8F-\uDE9D\uDE9F-\uDEA8\uDEB0-)"
+        LR"(\uDEDE\uDF05-\uDF0C\uDF0F\uDF10\uDF13-\uDF28\uDF2A-)"
+        LR"(\uDF30\uDF32\uDF33\uDF35-\uDF39\uDF3D\uDF50\uDF5D-\uDF61]|\uD805[\uDC00-)"
+        LR"(\uDC34\uDC47-\uDC4A\uDC80-\uDCAF\uDCC4\uDCC5\uDCC7\uDD80-\uDDAE\uDDD8-)"
+        LR"(\uDDDB\uDE00-\uDE2F\uDE44\uDE80-\uDEAA\uDF00-\uDF19]|\uD806[\uDCA0-)"
+        LR"(\uDCDF\uDCFF\uDE00\uDE0B-\uDE32\uDE3A\uDE50\uDE5C-\uDE83\uDE86-)"
+        LR"(\uDE89\uDEC0-\uDEF8]|\uD807[\uDC00-\uDC08\uDC0A-\uDC2E\uDC40\uDC72-)"
+        LR"(\uDC8F\uDD00-\uDD06\uDD08\uDD09\uDD0B-\uDD30\uDD46]|\uD808[\uDC00-\uDF99]|)"
+        LR"(\uD809[\uDC00-\uDC6E\uDC80-\uDD43]|[\uD80C\uD81C-\uD820\uD840-)"
+        LR"(\uD868\uD86A-\uD86C\uD86F-\uD872\uD874-\uD879][\uDC00-\uDFFF]|\uD80D[)"
+        LR"(\uDC00-\uDC2E]|\uD811[\uDC00-\uDE46]|\uD81A[\uDC00-\uDE38\uDE40-)"
+        LR"(\uDE5E\uDED0-\uDEED\uDF00-\uDF2F\uDF40-\uDF43\uDF63-\uDF77\uDF7D-\uDF8F]|)"
+        LR"(\uD81B[\uDF00-\uDF44\uDF50\uDF93-\uDF9F\uDFE0\uDFE1]|\uD821[\uDC00-\uDFEC])"
+        LR"(|\uD822[\uDC00-\uDEF2]|\uD82C[\uDC00-\uDD1E\uDD70-\uDEFB]|\uD82F[\uDC00-)"
+        LR"(\uDC6A\uDC70-\uDC7C\uDC80-\uDC88\uDC90-\uDC99]|\uD835[\uDC00-\uDC54\uDC56-)"
+        LR"(\uDC9C\uDC9E\uDC9F\uDCA2\uDCA5\uDCA6\uDCA9-\uDCAC\uDCAE-)"
+        LR"(\uDCB9\uDCBB\uDCBD-\uDCC3\uDCC5-\uDD05\uDD07-\uDD0A\uDD0D-\uDD14\uDD16-)"
+        LR"(\uDD1C\uDD1E-\uDD39\uDD3B-\uDD3E\uDD40-\uDD44\uDD46\uDD4A-\uDD50\uDD52-)"
+        LR"(\uDEA5\uDEA8-\uDEC0\uDEC2-\uDEDA\uDEDC-\uDEFA\uDEFC-\uDF14\uDF16-)"
+        LR"(\uDF34\uDF36-\uDF4E\uDF50-\uDF6E\uDF70-\uDF88\uDF8A-\uDFA8\uDFAA-)"
+        LR"(\uDFC2\uDFC4-\uDFCB]|\uD83A[\uDC00-\uDCC4\uDD00-\uDD43]|\uD83B[\uDE00-)"
+        LR"(\uDE03\uDE05-\uDE1F\uDE21\uDE22\uDE24\uDE27\uDE29-\uDE32\uDE34-)"
+        LR"(\uDE37\uDE39\uDE3B\uDE42\uDE47\uDE49\uDE4B\uDE4D-)"
+        LR"(\uDE4F\uDE51\uDE52\uDE54\uDE57\uDE59\uDE5B\uDE5D\uDE5F\uDE61\uDE62\uDE64)"
+        LR"(\uDE67-\uDE6A\uDE6C-\uDE72\uDE74-\uDE77\uDE79-\uDE7C\uDE7E\uDE80-)"
+        LR"(\uDE89\uDE8B-\uDE9B\uDEA1-\uDEA3\uDEA5-\uDEA9\uDEAB-\uDEBB]|\uD869[\uDC00-)"
+        LR"(\uDED6\uDF00-\uDFFF]|\uD86D[\uDC00-\uDF34\uDF40-\uDFFF]|\uD86E[\uDC00-)"
+        LR"(\uDC1D\uDC20-\uDFFF]|\uD873[\uDC00-\uDEA1\uDEB0-\uDFFF]|\uD87A[\uDC00-)"
+        LR"(\uDFE0]|\uD87E[\uDC00-\uDE1D])");
+    template<typename StringT>
+    MEOJSON_INLINE const std::wregex parser5<StringT>::unicode::id_continue = std::wregex(
+    LR"([\xAA\xB5\xBA\xC0-\xD6\xD8-\xF6\xF8-\u02C1\u02C6-\u02D1\u02E0-)"
+    LR"(\u02E4\u02EC\u02EE\u0300-\u0374\u0376\u0377\u037A-)"
+    LR"(\u037D\u037F\u0386\u0388-\u038A\u038C\u038E-\u03A1\u03A3-\u03F5\u03F7-)"
+    LR"(\u0481\u0483-\u0487\u048A-\u052F\u0531-\u0556\u0559\u0561-\u0587\u0591-)"
+    LR"(\u05BD\u05BF\u05C1\u05C2\u05C4\u05C5\u05C7\u05D0-\u05EA\u05F0-)"
+    LR"(\u05F2\u0610-\u061A\u0620-\u0669\u066E-\u06D3\u06D5-\u06DC\u06DF-)"
+    LR"(\u06E8\u06EA-\u06FC\u06FF\u0710-\u074A\u074D-\u07B1\u07C0-)"
+    LR"(\u07F5\u07FA\u0800-\u082D\u0840-\u085B\u0860-\u086A\u08A0-\u08B4\u08B6-)"
+    LR"(\u08BD\u08D4-\u08E1\u08E3-\u0963\u0966-\u096F\u0971-\u0983\u0985-)"
+    LR"(\u098C\u098F\u0990\u0993-\u09A8\u09AA-\u09B0\u09B2\u09B6-\u09B9\u09BC-)"
+    LR"(\u09C4\u09C7\u09C8\u09CB-\u09CE\u09D7\u09DC\u09DD\u09DF-\u09E3\u09E6-)"
+    LR"(\u09F1\u09FC\u0A01-\u0A03\u0A05-\u0A0A\u0A0F\u0A10\u0A13-\u0A28\u0A2A-)"
+    LR"(\u0A30\u0A32\u0A33\u0A35\u0A36\u0A38\u0A39\u0A3C\u0A3E-)"
+    LR"(\u0A42\u0A47\u0A48\u0A4B-\u0A4D\u0A51\u0A59-\u0A5C\u0A5E\u0A66-)"
+    LR"(\u0A75\u0A81-\u0A83\u0A85-\u0A8D\u0A8F-\u0A91\u0A93-\u0AA8\u0AAA-)"
+    LR"(\u0AB0\u0AB2\u0AB3\u0AB5-\u0AB9\u0ABC-\u0AC5\u0AC7-\u0AC9\u0ACB-)"
+    LR"(\u0ACD\u0AD0\u0AE0-\u0AE3\u0AE6-\u0AEF\u0AF9-\u0AFF\u0B01-\u0B03\u0B05-)"
+    LR"(\u0B0C\u0B0F\u0B10\u0B13-\u0B28\u0B2A-\u0B30\u0B32\u0B33\u0B35-)"
+    LR"(\u0B39\u0B3C-\u0B44\u0B47\u0B48\u0B4B-)"
+    LR"(\u0B4D\u0B56\u0B57\u0B5C\u0B5D\u0B5F-\u0B63\u0B66-)"
+    LR"(\u0B6F\u0B71\u0B82\u0B83\u0B85-\u0B8A\u0B8E-\u0B90\u0B92-)"
+    LR"(\u0B95\u0B99\u0B9A\u0B9C\u0B9E\u0B9F\u0BA3\u0BA4\u0BA8-\u0BAA\u0BAE-)"
+    LR"(\u0BB9\u0BBE-\u0BC2\u0BC6-\u0BC8\u0BCA-\u0BCD\u0BD0\u0BD7\u0BE6-)"
+    LR"(\u0BEF\u0C00-\u0C03\u0C05-\u0C0C\u0C0E-\u0C10\u0C12-\u0C28\u0C2A-)"
+    LR"(\u0C39\u0C3D-\u0C44\u0C46-\u0C48\u0C4A-\u0C4D\u0C55\u0C56\u0C58-)"
+    LR"(\u0C5A\u0C60-\u0C63\u0C66-\u0C6F\u0C80-\u0C83\u0C85-\u0C8C\u0C8E-)"
+    LR"(\u0C90\u0C92-\u0CA8\u0CAA-\u0CB3\u0CB5-\u0CB9\u0CBC-\u0CC4\u0CC6-)"
+    LR"(\u0CC8\u0CCA-\u0CCD\u0CD5\u0CD6\u0CDE\u0CE0-\u0CE3\u0CE6-)"
+    LR"(\u0CEF\u0CF1\u0CF2\u0D00-\u0D03\u0D05-\u0D0C\u0D0E-\u0D10\u0D12-)"
+    LR"(\u0D44\u0D46-\u0D48\u0D4A-\u0D4E\u0D54-\u0D57\u0D5F-\u0D63\u0D66-)"
+    LR"(\u0D6F\u0D7A-\u0D7F\u0D82\u0D83\u0D85-\u0D96\u0D9A-\u0DB1\u0DB3-)"
+    LR"(\u0DBB\u0DBD\u0DC0-\u0DC6\u0DCA\u0DCF-\u0DD4\u0DD6\u0DD8-\u0DDF\u0DE6-)"
+    LR"(\u0DEF\u0DF2\u0DF3\u0E01-\u0E3A\u0E40-\u0E4E\u0E50-)"
+    LR"(\u0E59\u0E81\u0E82\u0E84\u0E87\u0E88\u0E8A\u0E8D\u0E94-\u0E97\u0E99-)"
+    LR"(\u0E9F\u0EA1-\u0EA3\u0EA5\u0EA7\u0EAA\u0EAB\u0EAD-\u0EB9\u0EBB-)"
+    LR"(\u0EBD\u0EC0-\u0EC4\u0EC6\u0EC8-\u0ECD\u0ED0-\u0ED9\u0EDC-)"
+    LR"(\u0EDF\u0F00\u0F18\u0F19\u0F20-\u0F29\u0F35\u0F37\u0F39\u0F3E-)"
+    LR"(\u0F47\u0F49-\u0F6C\u0F71-\u0F84\u0F86-\u0F97\u0F99-\u0FBC\u0FC6\u1000-)"
+    LR"(\u1049\u1050-\u109D\u10A0-\u10C5\u10C7\u10CD\u10D0-\u10FA\u10FC-)"
+    LR"(\u1248\u124A-\u124D\u1250-\u1256\u1258\u125A-\u125D\u1260-\u1288\u128A-)"
+    LR"(\u128D\u1290-\u12B0\u12B2-\u12B5\u12B8-\u12BE\u12C0\u12C2-\u12C5\u12C8-)"
+    LR"(\u12D6\u12D8-\u1310\u1312-\u1315\u1318-\u135A\u135D-\u135F\u1380-)"
+    LR"(\u138F\u13A0-\u13F5\u13F8-\u13FD\u1401-\u166C\u166F-\u167F\u1681-)"
+    LR"(\u169A\u16A0-\u16EA\u16EE-\u16F8\u1700-\u170C\u170E-\u1714\u1720-)"
+    LR"(\u1734\u1740-\u1753\u1760-\u176C\u176E-\u1770\u1772\u1773\u1780-)"
+    LR"(\u17D3\u17D7\u17DC\u17DD\u17E0-\u17E9\u180B-\u180D\u1810-\u1819\u1820-)"
+    LR"(\u1877\u1880-\u18AA\u18B0-\u18F5\u1900-\u191E\u1920-\u192B\u1930-)"
+    LR"(\u193B\u1946-\u196D\u1970-\u1974\u1980-\u19AB\u19B0-\u19C9\u19D0-)"
+    LR"(\u19D9\u1A00-\u1A1B\u1A20-\u1A5E\u1A60-\u1A7C\u1A7F-\u1A89\u1A90-)"
+    LR"(\u1A99\u1AA7\u1AB0-\u1ABD\u1B00-\u1B4B\u1B50-\u1B59\u1B6B-\u1B73\u1B80-)"
+    LR"(\u1BF3\u1C00-\u1C37\u1C40-\u1C49\u1C4D-\u1C7D\u1C80-\u1C88\u1CD0-)"
+    LR"(\u1CD2\u1CD4-\u1CF9\u1D00-\u1DF9\u1DFB-\u1F15\u1F18-\u1F1D\u1F20-)"
+    LR"(\u1F45\u1F48-\u1F4D\u1F50-\u1F57\u1F59\u1F5B\u1F5D\u1F5F-\u1F7D\u1F80-)"
+    LR"(\u1FB4\u1FB6-\u1FBC\u1FBE\u1FC2-\u1FC4\u1FC6-\u1FCC\u1FD0-\u1FD3\u1FD6-)"
+    LR"(\u1FDB\u1FE0-\u1FEC\u1FF2-\u1FF4\u1FF6-)"
+    LR"(\u1FFC\u203F\u2040\u2054\u2071\u207F\u2090-\u209C\u20D0-)"
+    LR"(\u20DC\u20E1\u20E5-\u20F0\u2102\u2107\u210A-\u2113\u2115\u2119-)"
+    LR"(\u211D\u2124\u2126\u2128\u212A-\u212D\u212F-\u2139\u213C-\u213F\u2145-)"
+    LR"(\u2149\u214E\u2160-\u2188\u2C00-\u2C2E\u2C30-\u2C5E\u2C60-\u2CE4\u2CEB-)"
+    LR"(\u2CF3\u2D00-\u2D25\u2D27\u2D2D\u2D30-\u2D67\u2D6F\u2D7F-\u2D96\u2DA0-)"
+    LR"(\u2DA6\u2DA8-\u2DAE\u2DB0-\u2DB6\u2DB8-\u2DBE\u2DC0-\u2DC6\u2DC8-)"
+    LR"(\u2DCE\u2DD0-\u2DD6\u2DD8-\u2DDE\u2DE0-\u2DFF\u2E2F\u3005-\u3007\u3021-)"
+    LR"(\u302F\u3031-\u3035\u3038-\u303C\u3041-\u3096\u3099\u309A\u309D-)"
+    LR"(\u309F\u30A1-\u30FA\u30FC-\u30FF\u3105-\u312E\u3131-\u318E\u31A0-)"
+    LR"(\u31BA\u31F0-\u31FF\u3400-\u4DB5\u4E00-\u9FEA\uA000-\uA48C\uA4D0-)"
+    LR"(\uA4FD\uA500-\uA60C\uA610-\uA62B\uA640-\uA66F\uA674-\uA67D\uA67F-)"
+    LR"(\uA6F1\uA717-\uA71F\uA722-\uA788\uA78B-\uA7AE\uA7B0-\uA7B7\uA7F7-)"
+    LR"(\uA827\uA840-\uA873\uA880-\uA8C5\uA8D0-\uA8D9\uA8E0-)"
+    LR"(\uA8F7\uA8FB\uA8FD\uA900-\uA92D\uA930-\uA953\uA960-\uA97C\uA980-)"
+    LR"(\uA9C0\uA9CF-\uA9D9\uA9E0-\uA9FE\uAA00-\uAA36\uAA40-\uAA4D\uAA50-)"
+    LR"(\uAA59\uAA60-\uAA76\uAA7A-\uAAC2\uAADB-\uAADD\uAAE0-\uAAEF\uAAF2-)"
+    LR"(\uAAF6\uAB01-\uAB06\uAB09-\uAB0E\uAB11-\uAB16\uAB20-\uAB26\uAB28-)"
+    LR"(\uAB2E\uAB30-\uAB5A\uAB5C-\uAB65\uAB70-\uABEA\uABEC\uABED\uABF0-)"
+    LR"(\uABF9\uAC00-\uD7A3\uD7B0-\uD7C6\uD7CB-\uD7FB\uF900-\uFA6D\uFA70-)"
+    LR"(\uFAD9\uFB00-\uFB06\uFB13-\uFB17\uFB1D-\uFB28\uFB2A-\uFB36\uFB38-)"
+    LR"(\uFB3C\uFB3E\uFB40\uFB41\uFB43\uFB44\uFB46-\uFBB1\uFBD3-\uFD3D\uFD50-)"
+    LR"(\uFD8F\uFD92-\uFDC7\uFDF0-\uFDFB\uFE00-\uFE0F\uFE20-)"
+    LR"(\uFE2F\uFE33\uFE34\uFE4D-\uFE4F\uFE70-\uFE74\uFE76-\uFEFC\uFF10-)"
+    LR"(\uFF19\uFF21-\uFF3A\uFF3F\uFF41-\uFF5A\uFF66-\uFFBE\uFFC2-\uFFC7\uFFCA-)"
+    LR"(\uFFCF\uFFD2-\uFFD7\uFFDA-\uFFDC]|\uD800[\uDC00-\uDC0B\uDC0D-\uDC26\uDC28-)"
+    LR"(\uDC3A\uDC3C\uDC3D\uDC3F-\uDC4D\uDC50-\uDC5D\uDC80-\uDCFA\uDD40-)"
+    LR"(\uDD74\uDDFD\uDE80-\uDE9C\uDEA0-\uDED0\uDEE0\uDF00-\uDF1F\uDF2D-)"
+    LR"(\uDF4A\uDF50-\uDF7A\uDF80-\uDF9D\uDFA0-\uDFC3\uDFC8-\uDFCF\uDFD1-\uDFD5]|)"
+    LR"(\uD801[\uDC00-\uDC9D\uDCA0-\uDCA9\uDCB0-\uDCD3\uDCD8-\uDCFB\uDD00-)"
+    LR"(\uDD27\uDD30-\uDD63\uDE00-\uDF36\uDF40-\uDF55\uDF60-\uDF67]|\uD802[\uDC00-)"
+    LR"(\uDC05\uDC08\uDC0A-\uDC35\uDC37\uDC38\uDC3C\uDC3F-\uDC55\uDC60-)"
+    LR"(\uDC76\uDC80-\uDC9E\uDCE0-\uDCF2\uDCF4\uDCF5\uDD00-\uDD15\uDD20-)"
+    LR"(\uDD39\uDD80-\uDDB7\uDDBE\uDDBF\uDE00-\uDE03\uDE05\uDE06\uDE0C-)"
+    LR"(\uDE13\uDE15-\uDE17\uDE19-\uDE33\uDE38-\uDE3A\uDE3F\uDE60-\uDE7C\uDE80-)"
+    LR"(\uDE9C\uDEC0-\uDEC7\uDEC9-\uDEE6\uDF00-\uDF35\uDF40-\uDF55\uDF60-)"
+    LR"(\uDF72\uDF80-\uDF91]|\uD803[\uDC00-\uDC48\uDC80-\uDCB2\uDCC0-\uDCF2]|)"
+    LR"(\uD804[\uDC00-\uDC46\uDC66-\uDC6F\uDC7F-\uDCBA\uDCD0-\uDCE8\uDCF0-)"
+    LR"(\uDCF9\uDD00-\uDD34\uDD36-\uDD3F\uDD50-\uDD73\uDD76\uDD80-\uDDC4\uDDCA-)"
+    LR"(\uDDCC\uDDD0-\uDDDA\uDDDC\uDE00-\uDE11\uDE13-\uDE37\uDE3E\uDE80-)"
+    LR"(\uDE86\uDE88\uDE8A-\uDE8D\uDE8F-\uDE9D\uDE9F-\uDEA8\uDEB0-\uDEEA\uDEF0-)"
+    LR"(\uDEF9\uDF00-\uDF03\uDF05-\uDF0C\uDF0F\uDF10\uDF13-\uDF28\uDF2A-)"
+    LR"(\uDF30\uDF32\uDF33\uDF35-\uDF39\uDF3C-\uDF44\uDF47\uDF48\uDF4B-)"
+    LR"(\uDF4D\uDF50\uDF57\uDF5D-\uDF63\uDF66-\uDF6C\uDF70-\uDF74]|\uD805[\uDC00-)"
+    LR"(\uDC4A\uDC50-\uDC59\uDC80-\uDCC5\uDCC7\uDCD0-\uDCD9\uDD80-\uDDB5\uDDB8-)"
+    LR"(\uDDC0\uDDD8-\uDDDD\uDE00-\uDE40\uDE44\uDE50-\uDE59\uDE80-\uDEB7\uDEC0-)"
+    LR"(\uDEC9\uDF00-\uDF19\uDF1D-\uDF2B\uDF30-\uDF39]|\uD806[\uDCA0-)"
+    LR"(\uDCE9\uDCFF\uDE00-\uDE3E\uDE47\uDE50-\uDE83\uDE86-\uDE99\uDEC0-\uDEF8]|)"
+    LR"(\uD807[\uDC00-\uDC08\uDC0A-\uDC36\uDC38-\uDC40\uDC50-\uDC59\uDC72-)"
+    LR"(\uDC8F\uDC92-\uDCA7\uDCA9-\uDCB6\uDD00-\uDD06\uDD08\uDD09\uDD0B-)"
+    LR"(\uDD36\uDD3A\uDD3C\uDD3D\uDD3F-\uDD47\uDD50-\uDD59]|\uD808[\uDC00-\uDF99]|)"
+    LR"(\uD809[\uDC00-\uDC6E\uDC80-\uDD43]|[\uD80C\uD81C-\uD820\uD840-)"
+    LR"(\uD868\uD86A-\uD86C\uD86F-\uD872\uD874-\uD879][\uDC00-\uDFFF]|\uD80D[)"
+    LR"(\uDC00-\uDC2E]|\uD811[\uDC00-\uDE46]|\uD81A[\uDC00-\uDE38\uDE40-)"
+    LR"(\uDE5E\uDE60-\uDE69\uDED0-\uDEED\uDEF0-\uDEF4\uDF00-\uDF36\uDF40-)"
+    LR"(\uDF43\uDF50-\uDF59\uDF63-\uDF77\uDF7D-\uDF8F]|\uD81B[\uDF00-\uDF44\uDF50-)"
+    LR"(\uDF7E\uDF8F-\uDF9F\uDFE0\uDFE1]|\uD821[\uDC00-\uDFEC]|\uD822[\uDC00-)"
+    LR"(\uDEF2]|\uD82C[\uDC00-\uDD1E\uDD70-\uDEFB]|\uD82F[\uDC00-\uDC6A\uDC70-)"
+    LR"(\uDC7C\uDC80-\uDC88\uDC90-\uDC99\uDC9D\uDC9E]|\uD834[\uDD65-\uDD69\uDD6D-)"
+    LR"(\uDD72\uDD7B-\uDD82\uDD85-\uDD8B\uDDAA-\uDDAD\uDE42-\uDE44]|\uD835[\uDC00-)"
+    LR"(\uDC54\uDC56-\uDC9C\uDC9E\uDC9F\uDCA2\uDCA5\uDCA6\uDCA9-\uDCAC\uDCAE-)"
+    LR"(\uDCB9\uDCBB\uDCBD-\uDCC3\uDCC5-\uDD05\uDD07-\uDD0A\uDD0D-\uDD14\uDD16-)"
+    LR"(\uDD1C\uDD1E-\uDD39\uDD3B-\uDD3E\uDD40-\uDD44\uDD46\uDD4A-\uDD50\uDD52-)"
+    LR"(\uDEA5\uDEA8-\uDEC0\uDEC2-\uDEDA\uDEDC-\uDEFA\uDEFC-\uDF14\uDF16-)"
+    LR"(\uDF34\uDF36-\uDF4E\uDF50-\uDF6E\uDF70-\uDF88\uDF8A-\uDFA8\uDFAA-)"
+    LR"(\uDFC2\uDFC4-\uDFCB\uDFCE-\uDFFF]|\uD836[\uDE00-\uDE36\uDE3B-)"
+    LR"(\uDE6C\uDE75\uDE84\uDE9B-\uDE9F\uDEA1-\uDEAF]|\uD838[\uDC00-\uDC06\uDC08-)"
+    LR"(\uDC18\uDC1B-\uDC21\uDC23\uDC24\uDC26-\uDC2A]|\uD83A[\uDC00-\uDCC4\uDCD0-)"
+    LR"(\uDCD6\uDD00-\uDD4A\uDD50-\uDD59]|\uD83B[\uDE00-\uDE03\uDE05-)"
+    LR"(\uDE1F\uDE21\uDE22\uDE24\uDE27\uDE29-\uDE32\uDE34-)"
+    LR"(\uDE37\uDE39\uDE3B\uDE42\uDE47\uDE49\uDE4B\uDE4D-)"
+    LR"(\uDE4F\uDE51\uDE52\uDE54\uDE57\uDE59\uDE5B\uDE5D\uDE5F\uDE61\uDE62\uDE64)"
+    LR"(\uDE67-\uDE6A\uDE6C-\uDE72\uDE74-\uDE77\uDE79-\uDE7C\uDE7E\uDE80-)"
+    LR"(\uDE89\uDE8B-\uDE9B\uDEA1-\uDEA3\uDEA5-\uDEA9\uDEAB-\uDEBB]|\uD869[\uDC00-)"
+    LR"(\uDED6\uDF00-\uDFFF]|\uD86D[\uDC00-\uDF34\uDF40-\uDFFF]|\uD86E[\uDC00-)"
+    LR"(\uDC1D\uDC20-\uDFFF]|\uD873[\uDC00-\uDEA1\uDEB0-\uDFFF]|\uD87A[\uDC00-)"
+    LR"(\uDFE0]|\uD87E[\uDC00-\uDE1D]|\uDB40[\uDD00-\uDDEF]|[\u200C\u200D])");
+
+    template<typename StringT>
+    MEOJSON_INLINE bool parser5<StringT>::unicode::isSpaceSeparator(u8char ch)
+    {
+#ifdef _MSC_VER
+        std::wstring wstr = { (wchar_t)ch, 0 };
+#else
+        auto str = StringFromCharCode(ch);
+        auto len = str.size() + 1;
+        std::unique_ptr<wchar_t[]> p(new wchar_t[len]);
+        std::setlocale(LC_CTYPE, ".UTF8");
+        std::mbstowcs(p.get(), str.c_str(), len);
+        std::wstring wstr(p.get());
+#endif
+        return std::regex_search(wstr, unicode::space_separator);
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE bool parser5<StringT>::unicode::isIdStartChar(u8char ch)
+    {
+#ifdef _MSC_VER
+        std::wstring wstr = { (wchar_t)ch, 0 };
+#else
+        auto str = StringFromCharCode(ch);
+        auto len = str.size() + 1;
+        std::unique_ptr<wchar_t[]> p(new wchar_t[len]);
+        std::setlocale(LC_CTYPE, ".UTF8");
+        std::mbstowcs(p.get(), str.c_str(), len);
+        std::wstring wstr(p.get());
+#endif
+        return (ch >= 'a' && ch <= 'z') || (ch >= 'A' && ch <= 'Z') || (ch == '$') ||
+            (ch == '_') || std::regex_search(wstr, unicode::id_start);
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE bool parser5<StringT>::unicode::isIdContinueChar(u8char ch)
+    {
+#ifdef _MSC_VER
+        std::wstring wstr = { (wchar_t)ch, 0 };
+#else
+        auto str = StringFromCharCode(ch);
+        auto len = str.size() + 1;
+        std::unique_ptr<wchar_t[]> p(new wchar_t[len]);
+        std::setlocale(LC_CTYPE, ".UTF8");
+        std::mbstowcs(p.get(), str.c_str(), len);
+        std::wstring wstr(p.get());
+#endif
+        return (ch >= 'a' && ch <= 'z') || (ch >= 'A' && ch <= 'Z') ||
+            (ch >= '0' && ch <= '9') || (ch == '$') || (ch == '_') ||
+            std::regex_search(wstr, unicode::id_continue);
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE bool parser5<StringT>::unicode::isDigit(u8char ch)
+    {
+        auto str = StringFromCharCode(ch);
+        return std::regex_search(str, std::regex(R"([0-9])"));
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE bool parser5<StringT>::unicode::isHexDigit(u8char ch)
+    {
+        auto str = StringFromCharCode(ch);
+        return std::regex_search(str, std::regex(R"([0-9A-Fa-f])"));
+    }
+
+    /* constrators and callers */
+    template <typename StringT>
+    MEOJSON_INLINE std::optional<value> parse5(const StringT& content, std::string* error = nullptr)
+    {
+        return parser5<StringT>::parse(content, error);
+    }
+
+    /* Wrapper for handling input of C-style strings. */
+    template <typename CharT>
+    MEOJSON_INLINE std::optional<value> parse5(CharT* content, std::string* error = nullptr)
+    {
+        return parse5(std::basic_string_view<typename std::decay<CharT>::type>{content}, error);
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<value> parser5<StringT>::parse(const StringT& content, std::string* error)
+    {
+        try {
+            return parser5<StringT>(content.cbegin(), content.cend()).parse();
+        }
+        catch (json::parser5<StringT>::exception& ex) {
+            if (error) {
+                *error = ex.what();
+            }
+        }
+        return std::nullopt;
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<value> parser5<StringT>::parse()
+    {
+        do {
+            _token = lex();
+            parseStates(_parse_state);
+        } while (_token->type != TokenType::eof);
+
+        return _root;
+    }
+
+    /* escape and format */
+    template<typename StringT>
+    MEOJSON_INLINE void parser5<StringT>::literal(const std::string& s)
+    {
+        for (const auto& ch : s) {
+            char p = static_cast<char>(read());
+            if (p != ch) {
+                throw InvalidChar(_current_char, exceptionDetailInfo());
+            }
+        }
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::u8char> parser5<StringT>::escape()
+    {
+        auto c = peek(_cur, _end);
+        switch (c) {
+        case 'b':
+            read();
+            return '\b';
+
+        case 'f':
+            read();
+            return '\f';
+
+        case 'n':
+            read();
+            return '\n';
+
+        case 'r':
+            read();
+            return '\r';
+
+        case 't':
+            read();
+            return '\t';
+
+        case 'v':
+            read();
+            return '\v';
+
+        case '0':
+            read();
+            if (unicode::isDigit(peek(_cur, _end))) {
+                throw InvalidChar(_current_char, exceptionDetailInfo());
+            }
+
+            return '\0';
+
+        case 'x':
+            read();
+            return hexEscape();
+
+        case 'u':
+            read();
+            return unicodeEscape();
+
+        case '\n':
+        case 0x2028:
+        case 0x2029:
+            read();
+            return 0;
+
+        case '\r':
+            read();
+            if (peek(_cur, _end) == '\n') {
+                read();
+            }
+
+            return std::nullopt;
+
+        case '1':
+        case '2':
+        case '3':
+        case '4':
+        case '5':
+        case '6':
+        case '7':
+        case '8':
+        case '9':
+            throw InvalidChar(_current_char, exceptionDetailInfo());
+        default:
+            if (c == 0) {
+                throw InvalidChar(_current_char, exceptionDetailInfo());
+            }
+        }
+
+        return read();
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE typename parser5<StringT>::u8char parser5<StringT>::hexEscape()
+    {
+        std::string buffer = "";
+        auto c = peek(_cur, _end);
+
+        if (!unicode::isHexDigit(c)) {
+            throw InvalidChar(_current_char, exceptionDetailInfo());
+        }
+
+        buffer += static_cast<char>(read());
+
+        c = peek(_cur, _end);
+        if (!unicode::isHexDigit(c)) {
+            throw InvalidChar(_current_char, exceptionDetailInfo());
+        }
+
+        buffer += static_cast<char>(read());
+
+        return std::stoi(buffer, nullptr, 16);
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE typename parser5<StringT>::u8char parser5<StringT>::unicodeEscape()
+    {
+        std::string buffer;
+        int count = 4;
+        while (count-- > 0) {
+            auto c = peek(_cur, _end);
+            if (!unicode::isHexDigit(c)) {
+                throw InvalidChar(_current_char, exceptionDetailInfo());
+            }
+            buffer += StringFromCharCode(read());
+        }
+
+        return std::stoull(buffer, nullptr, 16);
+    }
+
+    /* utf-8 reader */
+    template<typename StringT>
+    MEOJSON_INLINE typename parser5<StringT>::u8char parser5<StringT>::peek(StringIterT& begin,
+                                  const StringIterT& end,
+                                  size_t* plen)
+    {
+        if (begin == end) {
+            if (plen)
+                *plen = 0;
+            return 0;
+        }
+        uint8_t head = (*begin);
+        uint64_t ch = head;
+        size_t len = 1;
+        while (begin != end && (head & 0b11000000) > 0b10000000) {
+            head <<= 1;
+            ++len;
+            ch <<= 8;
+            ch += (uint8_t)(*(begin + len - 1));
+        }
+        if (plen) {
+            *plen = len;
+        }
+        return ch;
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE typename parser5<StringT>::u8char parser5<StringT>::peek(const std::string& str)
+    {
+        auto begin = str.begin();
+        return peek(begin, str.cend());
+    }
+    MEOJSON_INLINE constexpr size_t operator"" _sz(unsigned long long size) { return size; }
+    template<typename StringT>
+    MEOJSON_INLINE typename parser5<StringT>::u8char parser5<StringT>::read()
+    {
+        size_t len = 0;
+        _current_char = peek(_cur, _end, &len);
+        if (_current_char == '\n') {
+            _line++;
+            _col = 0;
+            _print_len = 0;
+            _line_begin_cur = _cur + 1;
+        }
+        else if (_current_char > 0) {
+            _col++;
+        }
+
+        if (len > 0) {
+            _print_len += (std::min)(len, 2_sz);
+            _cur += len;
+        }
+        return _current_char;
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::string parser5<StringT>::StringFromCharCode(typename parser5<StringT>::u8char code)
+    {
+        if (code == 0)
+            return "";
+        std::string str;
+        for (auto i = 0; i < 8; ++i) {
+            auto ch = (0xff & code);
+            if (ch)
+                str.insert(0, 1, static_cast<char>(ch));
+            code >>= 8;
+        }
+        return str;
+    }
+
+    /* lex, parse, token */
+
+    template<typename StringT>
+    MEOJSON_INLINE typename parser5<StringT>::Token parser5<StringT>::newToken(TokenType type, value value)
+    {
+        Token token;
+        token.type = type;
+        token._value = value;
+        token.line = _line;
+        token.col = _col;
+        return token;
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE typename parser5<StringT>::Token parser5<StringT>::lex()
+    {
+        _lex_state = LexState::default_;
+        _buffer = "";
+        _double_quote = false;
+        _sign = 1;
+
+        std::optional<Token> token;
+
+        for (;;) {
+            _current_char = peek(_cur, _end);
+
+            token = lexStates(_lex_state);
+            if (token.has_value()) {
+                return token.value();
+            }
+        }
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::Token> parser5<StringT>::lex_default()
+    {
+        switch (_current_char) {
+        case '\t':
+        case '\v':
+        case '\f':
+        case ' ':
+        case '\n':
+        case '\r':
+        case 0x00A0:
+        case 0xFEFF:
+        case 0x2028:
+        case 0x2029:
+            read();
+            return std::nullopt;
+        case '/':
+            read();
+            _lex_state = LexState::comment;
+            return std::nullopt;
+        case 0:
+            read();
+            return newToken(TokenType::eof, value());
+        }
+
+        // if (_current_char.size() == 0) {
+        //   read();
+        //   return newToken("eof");
+        // }
+
+        if (unicode::isSpaceSeparator(_current_char)) {
+            read();
+            return std::nullopt;
+        }
+
+        //      throw InvalidLexState();
+        return lexStates((LexState)_parse_state);
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::Token> parser5<StringT>::lex_comment()
+    {
+        switch (_current_char) {
+        case '*':
+            read();
+            _lex_state = LexState::multiLineComment;
+            return std::nullopt;
+
+        case '/':
+            read();
+            _lex_state = LexState::singleLineComment;
+            return std::nullopt;
+        }
+
+        throw InvalidChar(_current_char, exceptionDetailInfo());
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::Token> parser5<StringT>::lex_multiLineComment()
+    {
+        if (_current_char == '*') {
+            read();
+            _lex_state = LexState::multiLineCommentAsterisk;
+            return std::nullopt;
+        }
+
+        if (_current_char == 0) {
+            throw InvalidChar(_current_char, exceptionDetailInfo());
+        }
+
+        read();
+        return std::nullopt;
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::Token> parser5<StringT>::lex_multiLineCommentAsterisk()
+    {
+        switch (_current_char) {
+        case '*':
+            read();
+            return std::nullopt;
+
+        case '/':
+            read();
+            _lex_state = LexState::default_;
+            return std::nullopt; //$
+
+        default:
+            if (_current_char == 0) {
+                throw InvalidChar(_current_char, exceptionDetailInfo());
+            }
+        }
+
+        read();
+        _lex_state = LexState::multiLineComment;
+        return std::nullopt;
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::Token> parser5<StringT>::lex_singleLineComment()
+    {
+        switch (_current_char) {
+        case '\n':
+        case '\r':
+        case 0x2028:
+        case 0x2029:
+            read();
+            _lex_state = LexState::default_;
+            return std::nullopt;
+        case 0:
+            read();
+            return newToken(TokenType::eof, value());
+        }
+        read();
+        return std::nullopt;
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::Token> parser5<StringT>::lex_value()
+    {
+        switch (_current_char) {
+        case '{':
+        case '[':
+            return newToken(TokenType::punctuator, value(StringFromCharCode(read())));
+        case 'n':
+            read();
+            literal("ull");
+            return newToken(TokenType::null, value());
+        case 't':
+            read();
+            literal("rue");
+            return newToken(TokenType::boolean, value(true));
+        case 'f':
+            read();
+            literal("alse");
+            return newToken(TokenType::boolean, value(false));
+        case '-':
+        case '+':
+            if (read() == '-') {
+                _sign = -1;
+            }
+            _lex_state = LexState::sign;
+            return std::nullopt;
+        case '.':
+            _buffer = StringFromCharCode(read());
+            _lex_state = LexState::decimalPointLeading;
+            return std::nullopt;
+
+        case '0':
+            _buffer = StringFromCharCode(read());
+            _lex_state = LexState::zero;
+            return std::nullopt;
+        case '1':
+        case '2':
+        case '3':
+        case '4':
+        case '5':
+        case '6':
+        case '7':
+        case '8':
+        case '9':
+            _buffer = StringFromCharCode(read());
+            _lex_state = LexState::decimalInteger;
+            return std::nullopt;
+        case 'I':
+            read();
+            literal("nfinity");
+            return newToken(TokenType::numeric, INFINITY);
+        case 'N':
+            read();
+            literal("aN");
+            return newToken(TokenType::numeric, NAN);
+        case '\"':
+        case '\'':
+            _double_quote = (read() == '\"');
+            _buffer = "";
+            _lex_state = LexState::string;
+            return std::nullopt;
+        }
+        throw InvalidChar(_current_char, exceptionDetailInfo());
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::Token> parser5<StringT>::lex_identifierNameStartEscape()
+    {
+        if (_current_char != 'u') {
+            throw InvalidChar(_current_char, exceptionDetailInfo());
+        }
+        read();
+        auto u = unicodeEscape();
+        switch (u) {
+        case '$':
+        case '_':
+            break;
+        default:
+            if (!unicode::isIdStartChar(u)) {
+                throw InvalidIdentifier("", exceptionDetailInfo());
+            }
+            break;
+        }
+        _buffer += StringFromCharCode(u);
+        _lex_state = LexState::identifierName;
+        return std::nullopt;
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::Token> parser5<StringT>::lex_identifierName()
+    {
+        switch (_current_char) {
+        case '$':
+        case '_':
+        case 0x200C:
+        case 0x200D:
+            _buffer += StringFromCharCode(read());
+            return std::nullopt;
+        case '\\':
+            read();
+            _lex_state = LexState::identifierNameEscape;
+            return std::nullopt;
+        }
+
+        if (unicode::isIdContinueChar(_current_char)) {
+            _buffer += StringFromCharCode(read());
+            return std::nullopt;
+        }
+
+        return newToken(TokenType::identifier, _buffer);
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::Token> parser5<StringT>::lex_identifierNameEscape()
+    {
+        if (_current_char != 'u') {
+            throw InvalidChar(_current_char, exceptionDetailInfo());
+        }
+        read();
+        auto u = unicodeEscape();
+        switch (u) {
+        case '$':
+        case '_':
+        case 0x200C:
+        case 0x200D:
+            break;
+        default:
+            if (!unicode::isIdStartChar(u)) {
+                throw InvalidIdentifier("", exceptionDetailInfo());
+            }
+            break;
+        }
+        _buffer += StringFromCharCode(u);
+        _lex_state = LexState::identifierName;
+        return std::nullopt;
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::Token> parser5<StringT>::lex_sign()
+    {
+        switch (_current_char) {
+        case '.':
+            _buffer = StringFromCharCode(read());
+            _lex_state = LexState::decimalPointLeading;
+            return std::nullopt;
+
+        case '0':
+            _buffer = StringFromCharCode(read());
+            _lex_state = LexState::zero;
+            return std::nullopt;
+
+        case '1':
+        case '2':
+        case '3':
+        case '4':
+        case '5':
+        case '6':
+        case '7':
+        case '8':
+        case '9':
+            _buffer = StringFromCharCode(read());
+            _lex_state = LexState::decimalInteger;
+            return std::nullopt;
+
+        case 'I':
+            read();
+            literal("nfinity");
+            return newToken(TokenType::numeric, _sign * INFINITY);
+
+        case 'N':
+            read();
+            literal("aN");
+            return newToken(TokenType::numeric, NAN);
+        }
+        throw InvalidChar(_current_char, exceptionDetailInfo());
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::Token> parser5<StringT>::lex_zero()
+    {
+        switch (_current_char) {
+        case '.':
+            _buffer += StringFromCharCode(read());
+            _lex_state = LexState::decimalPoint;
+            return std::nullopt; //$
+
+        case 'e':
+        case 'E':
+            _buffer += StringFromCharCode(read());
+            _lex_state = LexState::decimalExponent;
+            return std::nullopt; //$
+
+        case 'x':
+        case 'X':
+            _buffer += StringFromCharCode(read());
+            _lex_state = LexState::hexadecimal;
+            return std::nullopt; //$
+        }
+        return newToken(TokenType::numeric, _sign * 0);
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::Token> parser5<StringT>::lex_decimalInteger()
+    {
+        switch (_current_char) {
+        case '.':
+            _buffer += StringFromCharCode(read());
+            _lex_state = LexState::decimalPoint;
+            return std::nullopt;
+        case 'e':
+        case 'E':
+            _buffer += StringFromCharCode(read());
+            _lex_state = LexState::decimalExponent;
+            return std::nullopt; //$
+        }
+        if (unicode::isDigit(_current_char)) {
+            _buffer += StringFromCharCode(read());
+            return std::nullopt;
+        }
+
+        return newToken(TokenType::numeric, _sign * std::stod(_buffer));
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::Token> parser5<StringT>::lex_decimalPointLeading()
+    {
+        if (unicode::isDigit(_current_char)) {
+            _buffer += StringFromCharCode(read());
+            _lex_state = LexState::decimalFraction;
+            return std::nullopt;
+        }
+        throw InvalidChar(_current_char, exceptionDetailInfo());
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::Token> parser5<StringT>::lex_decimalPoint()
+    {
+        switch (_current_char) {
+        case 'e':
+        case 'E':
+            _buffer += StringFromCharCode(read());
+            _lex_state = LexState::decimalExponent;
+            return std::nullopt; //$
+        }
+        if (unicode::isDigit(_current_char)) {
+            _buffer += StringFromCharCode(read());
+            _lex_state = LexState::decimalFraction;
+            return std::nullopt;
+        }
+
+        return newToken(TokenType::numeric, _sign * std::stod(_buffer));
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::Token> parser5<StringT>::lex_decimalFraction()
+    {
+        switch (_current_char) {
+        case 'e':
+        case 'E':
+            _buffer += StringFromCharCode(read());
+            _lex_state = LexState::decimalExponent;
+            return std::nullopt; //$
+        }
+        if (unicode::isDigit(_current_char)) {
+            _buffer += StringFromCharCode(read());
+            return std::nullopt;
+        }
+
+        return newToken(TokenType::numeric, _sign * std::stod(_buffer));
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::Token> parser5<StringT>::lex_decimalExponent()
+    {
+        switch (_current_char) {
+        case '+':
+        case '-':
+            _buffer += StringFromCharCode(read());
+            _lex_state = LexState::decimalExponentSign;
+            return std::nullopt; //$
+        }
+
+        if (unicode::isDigit(_current_char)) {
+            _buffer += StringFromCharCode(read());
+            _lex_state = LexState::decimalExponentInteger;
+            return std::nullopt;
+        }
+        throw InvalidChar(_current_char, exceptionDetailInfo());
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::Token> parser5<StringT>::lex_decimalExponentSign()
+    {
+        if (unicode::isDigit(_current_char)) {
+            _buffer += StringFromCharCode(read());
+            _lex_state = LexState::decimalExponentInteger;
+            return std::nullopt;
+        }
+        throw InvalidChar(_current_char, exceptionDetailInfo());
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::Token> parser5<StringT>::lex_decimalExponentInteger()
+    {
+        if (unicode::isDigit(_current_char)) {
+            _buffer += StringFromCharCode(read());
+            return std::nullopt;
+        }
+        return newToken(TokenType::numeric, _sign * std::stod(_buffer));
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::Token> parser5<StringT>::lex_hexadecimal()
+    {
+        if (unicode::isHexDigit(_current_char)) {
+            _buffer += StringFromCharCode(read());
+            _lex_state = LexState::hexadecimalInteger;
+            return std::nullopt;
+        }
+        throw InvalidChar(_current_char, exceptionDetailInfo());
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::Token> parser5<StringT>::lex_hexdecimalInteger()
+    {
+        if (unicode::isHexDigit(_current_char)) {
+            _buffer += StringFromCharCode(read());
+            return std::nullopt;
+        }
+        return newToken(TokenType::numeric, _sign * std::stod(_buffer));
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::Token> parser5<StringT>::lex_string()
+    {
+        switch (_current_char) {
+        case '\\':
+            read();
+            _buffer += StringFromCharCode(escape().value_or(0));
+            return std::nullopt;
+        case '\"':
+            if (_double_quote) {
+                read();
+                return newToken(TokenType::string, _buffer);
+            }
+            _buffer += StringFromCharCode(read());
+            return std::nullopt;
+        case '\'':
+            if (!_double_quote) {
+                read();
+                return newToken(TokenType::string, _buffer);
+            }
+            _buffer += StringFromCharCode(read());
+            return std::nullopt;
+        case '\n':
+        case '\r':
+            throw InvalidChar(_current_char, exceptionDetailInfo());
+        case 0x2028:
+        case 0x2029:
+            // throw separatorChar(_current_char);
+            break;
+        default:
+            if (_current_char == 0) {
+                throw InvalidChar(_current_char, exceptionDetailInfo());
+            }
+        }
+        _buffer += StringFromCharCode(read());
+        return std::nullopt;
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::Token> parser5<StringT>::lex_start()
+    {
+        switch (_current_char) {
+        case '{':
+        case '[':
+            return newToken(TokenType::punctuator, StringFromCharCode(read()));
+        }
+
+        _lex_state = LexState::value;
+        return std::nullopt;
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::Token> parser5<StringT>::lex_beforePropertyName()
+    {
+        switch (_current_char) {
+        case '$':
+        case '_':
+            _buffer = StringFromCharCode(read());
+            _lex_state = LexState::identifierName;
+            return std::nullopt;
+        case '\\':
+            read();
+            _lex_state = LexState::identifierNameStartEscape;
+            return std::nullopt;
+        case '}':
+            return newToken(TokenType::punctuator, StringFromCharCode(read()));
+        case '\"':
+        case '\'':
+            _double_quote = (read() == '\"');
+            _lex_state = LexState::string;
+            return std::nullopt;
+        }
+
+        if (unicode::isIdStartChar(_current_char)) {
+            _buffer += StringFromCharCode(read());
+            _lex_state = LexState::identifierName;
+            return std::nullopt;
+        }
+
+        throw InvalidChar(_current_char, exceptionDetailInfo());
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::Token> parser5<StringT>::lex_afterPropertyName()
+    {
+        if (_current_char == ':') {
+            return newToken(TokenType::punctuator, StringFromCharCode(read()));
+        }
+        throw InvalidChar(_current_char, exceptionDetailInfo());
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::Token> parser5<StringT>::lex_beforePropertyValue()
+    {
+        _lex_state = LexState::value;
+        return std::nullopt;
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::Token> parser5<StringT>::lex_afterPropertyValue()
+    {
+        switch (_current_char) {
+        case ',':
+        case '}':
+            return newToken(TokenType::punctuator, StringFromCharCode(read()));
+        }
+        throw InvalidChar(_current_char, exceptionDetailInfo());
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::Token> parser5<StringT>::lex_beforeArrayValue()
+    {
+        if (_current_char == ']') {
+            return newToken(TokenType::punctuator, StringFromCharCode(read()));
+        }
+        _lex_state = LexState::value;
+        return std::nullopt;
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::Token> parser5<StringT>::lex_afterArrayValue()
+    {
+        switch (_current_char) {
+        case ',':
+        case ']':
+            return newToken(TokenType::punctuator, StringFromCharCode(read()));
+        }
+
+        throw InvalidChar(_current_char, exceptionDetailInfo());
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::Token> parser5<StringT>::lex_end()
+    {
+        throw InvalidChar(_current_char, exceptionDetailInfo());
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE std::optional<typename parser5<StringT>::Token> parser5<StringT>::lexStates(LexState state)
+    {
+        switch (state) {
+        case LexState::default_:
+            return lex_default();
+        case LexState::comment:
+            return lex_comment();
+        case LexState::multiLineComment:
+            return lex_multiLineComment();
+        case LexState::multiLineCommentAsterisk:
+            return lex_multiLineCommentAsterisk();
+        case LexState::singleLineComment:
+            return lex_singleLineComment();
+        case LexState::value:
+            return lex_value();
+        case LexState::identifierNameStartEscape:
+            return lex_identifierNameStartEscape();
+        case LexState::identifierName:
+            return lex_identifierName();
+        case LexState::identifierNameEscape:
+            return lex_identifierNameEscape();
+        case LexState::sign:
+            return lex_sign();
+        case LexState::zero:
+            return lex_zero();
+        case LexState::decimalInteger:
+            return lex_decimalInteger();
+        case LexState::decimalPointLeading:
+            return lex_decimalPointLeading();
+        case LexState::decimalPoint:
+            return lex_decimalPoint();
+        case LexState::decimalFraction:
+            return lex_decimalFraction();
+        case LexState::decimalExponent:
+            return lex_decimalExponent();
+        case LexState::decimalExponentSign:
+            return lex_decimalExponentSign();
+        case LexState::decimalExponentInteger:
+            return lex_decimalExponentInteger();
+        case LexState::hexadecimal:
+            return lex_hexadecimal();
+        case LexState::hexadecimalInteger:
+            return lex_hexdecimalInteger();
+        case LexState::string:
+            return lex_string();
+        case LexState::start:
+            return lex_start();
+        case LexState::beforePropertyName:
+            return lex_beforePropertyName();
+        case LexState::afterPropertyName:
+            return lex_afterPropertyName();
+        case LexState::beforePropertyValue:
+            return lex_beforePropertyValue();
+        case LexState::afterPropertyValue:
+            return lex_afterPropertyValue();
+        case LexState::beforeArrayValue:
+            return lex_beforeArrayValue();
+        case LexState::afterArrayValue:
+            return lex_afterArrayValue();
+        case LexState::end:
+            return lex_end();
+        }
+
+        // throw
+        return std::nullopt;
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE void parser5<StringT>::parse_start()
+    {
+        if (_token->type == TokenType::eof) {
+            throw InvalidEOF("", exceptionDetailInfo());
+        }
+
+        push();
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE void parser5<StringT>::parse_beforePropertyName()
+    {
+        switch (_token->type) {
+        case TokenType::identifier:
+        case TokenType::string:
+            _key = _token->_value.as_string();
+            _parse_state = ParseState::afterPropertyName;
+            break;
+        case TokenType::punctuator:
+            pop();
+            break;
+        case TokenType::eof:
+            throw InvalidEOF("", exceptionDetailInfo());
+            break;
+        default:
+
+            break;
+        }
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE void parser5<StringT>::parse_afterPropertyName()
+    {
+        if (_token->type == TokenType::eof) {
+            throw InvalidEOF("", exceptionDetailInfo());
+        }
+
+        _parse_state = ParseState::beforePropertyValue;
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE void parser5<StringT>::parse_beforePropertyValue()
+    {
+        if (_token->type == TokenType::eof) {
+            throw InvalidEOF("", exceptionDetailInfo());
+        }
+        push();
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE void parser5<StringT>::parse_beforeArrayValue()
+    {
+        if (_token->type == TokenType::eof) {
+            throw InvalidEOF("", exceptionDetailInfo());
+        }
+
+        if (_token->type == TokenType::punctuator &&
+            _token->_value.as_string()[0] == ']') {
+            pop();
+            return;
+        }
+
+        push();
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE void parser5<StringT>::parse_afterPropertyValue()
+    {
+        if (_token->type == TokenType::eof) {
+            throw InvalidEOF("", exceptionDetailInfo());
+        }
+
+        switch (_token->_value.as_string()[0]) {
+        case ',':
+            _parse_state = ParseState::beforePropertyName;
+            break;
+        case '}':
+            pop();
+            break;
+        }
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE void parser5<StringT>::parse_afterArrayValue()
+    {
+        if (_token->type == TokenType::eof) {
+            throw InvalidEOF("", exceptionDetailInfo());
+        }
+        switch (_token->_value.as_string()[0]) {
+        case ',':
+            _parse_state = ParseState::beforeArrayValue;
+            break;
+        case ']':
+            pop();
+            break;
+        }
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE void parser5<StringT>::parse_end() {}
+
+    template<typename StringT>
+    MEOJSON_INLINE void parser5<StringT>::parseStates(ParseState state)
+    {
+        switch (state) {
+        case ParseState::start:
+            parse_start();
+            break;
+        case ParseState::beforePropertyName:
+            parse_beforePropertyName();
+            break;
+        case ParseState::afterPropertyName:
+            parse_afterPropertyName();
+            break;
+        case ParseState::beforePropertyValue:
+            parse_beforePropertyValue();
+            break;
+        case ParseState::beforeArrayValue:
+            parse_beforeArrayValue();
+            break;
+        case ParseState::afterPropertyValue:
+            parse_afterPropertyValue();
+            break;
+        case ParseState::afterArrayValue:
+            parse_afterArrayValue();
+            break;
+        default:
+            break;
+        }
+    }
+    /* stack operation */
+    template<typename StringT>
+    MEOJSON_INLINE void parser5<StringT>::push()
+    {
+        value v;
+        value* pv = nullptr; // only for access
+        switch (_token->type) {
+        case TokenType::punctuator: {
+            switch (_token->_value.as_string()[0]) {
+            case '{':
+                v = object();
+                break;
+            case '[':
+                v = array();
+                break;
+            default:
+                break;
+            }
+        } break;
+        case TokenType::null:
+        case TokenType::boolean:
+        case TokenType::numeric:
+        case TokenType::string:
+            std::swap(v, _token->_value);
+            break;
+        default:
+            break;
+        }
+
+        if (!_root.has_value()) {
+            _root = std::move(v);
+            pv = &_root.value();
+        }
+        else {
+            auto parent = _stack.top();
+            if (parent->is_array()) {
+                parent->as_array().emplace_back(std::move(v));
+                pv = &parent->as_array()[parent->as_array().size() - 1];
+            }
+            else {
+                parent->as_object()[_key] = std::move(v);
+                pv = &parent->as_object()[_key];
+            }
+        }
+
+        if (pv->is_object() || pv->is_array()) {
+            _stack.emplace(pv);
+            if (pv->is_array()) {
+                _parse_state = ParseState::beforeArrayValue;
+            }
+            else {
+                _parse_state = ParseState::beforePropertyName;
+            }
+        }
+        else {
+            if (_stack.empty()) {
+                _parse_state = ParseState::end;
+            }
+            else if (_stack.top()->is_array()) {
+                _parse_state = ParseState::afterArrayValue;
+            }
+            else {
+                _parse_state = ParseState::afterPropertyValue;
+            }
+        }
+    }
+
+    template<typename StringT>
+    MEOJSON_INLINE void parser5<StringT>::pop()
+    {
+        _stack.pop();
+
+        if (_stack.empty()) {
+            _parse_state = ParseState::end;
+        }
+        else if (_stack.top()->is_array()) {
+            _parse_state = ParseState::afterArrayValue;
+        }
+        else {
+            _parse_state = ParseState::afterPropertyValue;
+        }
+    }
+} // namespace json