Moved buffer management into the lexer class and implemented YYFILL so that streams are read incrementally.
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					 1 changed files with 50 additions and 16 deletions
				
			
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			@ -3046,11 +3046,20 @@ class basic_json
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        using lexer_char_t = unsigned char;
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        /// constructor with a given buffer
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        inline lexer(const string_t& s) noexcept
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            : m_content(reinterpret_cast<const lexer_char_t*>(s.c_str()))
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		inline lexer(const string_t& s) noexcept
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		: m_buffer(s), m_stream(nullptr)
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		{
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			m_content = reinterpret_cast<const lexer_char_t*>(s.c_str());
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			m_start = m_cursor = m_content;
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			m_limit = m_content + s.size();
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		}
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		inline lexer(std::istream* s) noexcept
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            : m_stream(s)
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        {
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			getline(*m_stream, m_buffer);
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			m_content = reinterpret_cast<const lexer_char_t*>(m_buffer.c_str());
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            m_start = m_cursor = m_content;
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            m_limit = m_content + s.size();
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            m_limit = m_content + m_buffer.size();
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        }
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        /// default constructor
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			@ -3182,6 +3191,8 @@ class basic_json
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            // remember the begin of the token
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            m_start = m_cursor;
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#define YYFILL(n)       { size_t offset_marker = m_marker - m_start; yyfill(n);  m_marker = m_start + offset_marker; }
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            /*!re2c
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                re2c:define:YYCTYPE  = lexer_char_t;
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                re2c:define:YYCURSOR = m_cursor;
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			@ -3190,7 +3201,6 @@ class basic_json
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                re2c:indent:string   = "    ";
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                re2c:indent:top      = 1;
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                re2c:labelprefix     = "basic_json_parser_";
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                re2c:yyfill:enable   = 0;
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                // whitespace
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                ws = [ \t\n\r]+;
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			@ -3240,8 +3250,28 @@ class basic_json
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                // anything else is an error
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                .              { return token_type::parse_error; }
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             */
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        }
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		void yyfill(int n) noexcept
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		{
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			if (not m_stream or not *m_stream) return;
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			ssize_t offset_start  = m_start  - m_content;
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			ssize_t offset_cursor = m_cursor - m_start;
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			ssize_t offset_limit  = m_limit  - m_start;
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			m_buffer.erase(0, offset_start);
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			std::string line;
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			std::getline(*m_stream, line);
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			m_buffer += line;
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			m_content = reinterpret_cast<const lexer_char_t*>(m_buffer.c_str()); //reinterpret_cast<lexer_char_t*>(endptr)
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			m_start  = m_content + offset_start;
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			m_cursor = m_start + offset_cursor;
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			m_limit  = m_start + offset_limit;
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		}
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        /// return string representation of last read token
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        inline string_t get_token() const noexcept
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        {
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			@ -3404,14 +3434,20 @@ class basic_json
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        }
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      private:
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        /// optional input stream
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        std::istream* m_stream;
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        /// the buffer
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        string_t m_buffer;
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        /// the buffer pointer
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        const lexer_char_t* m_content = nullptr;
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        /// pointer to he beginning of the current symbol
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        /// pointer to the beginning of the current symbol
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        const lexer_char_t* m_start = nullptr;
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        /// pointer to the current symbol
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        const lexer_char_t* m_cursor = nullptr;
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        /// pointer to the end of the buffer
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        const lexer_char_t* m_limit = nullptr;
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        /// YYSTATE
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        int m_state;
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    };
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    /*!
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			@ -3421,24 +3457,24 @@ class basic_json
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    {
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      public:
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        /// constructor for strings
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        inline parser(const string_t& s) : m_buffer(s), m_lexer(m_buffer)
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		inline parser(const string_t& s) : m_lexer(s)
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        {
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            // read first token
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            get_token();
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        }
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        /// a parser reading from an input stream
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        inline parser(std::istream& _is)
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		inline parser(std::istream& _is) : m_lexer(&_is)
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        {
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            while (_is)
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            {
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                string_t input_line;
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                std::getline(_is, input_line);
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                m_buffer += input_line;
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            }
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//            while (_is)
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//            {
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//                string_t input_line;
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//                std::getline(_is, input_line);
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//                m_buffer += input_line;
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//            }
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            // initializer lexer
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            m_lexer = lexer(m_buffer);
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//			m_lexer = std::move(lexer(_is));
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            // read first token
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            get_token();
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			@ -3625,8 +3661,6 @@ class basic_json
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        }
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      private:
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        /// the buffer
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        string_t m_buffer;
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        /// the type of the last read token
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        typename lexer::token_type last_token = lexer::token_type::uninitialized;
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        /// the lexer
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