我怎样才能简单地使用无法识别的字符？

Question

感谢 Boost Spirit 库，我设法解析了一个 pgn 文件，但只要有一些我没有“预料到”的字符，它就会失败。

这是我的精神语法：

#include <boost/spirit/include/qi.hpp>
#include <boost/spirit/include/phoenix.hpp>
#include <boost/fusion/include/adapt_struct.hpp>

BOOST_FUSION_ADAPT_STRUCT(
    loloof64::pgn_tag,
    (std::string, key),
    (std::string, value)
)

BOOST_FUSION_ADAPT_STRUCT(
    loloof64::game_move,
    (unsigned, move_number),
    (std::string, move_turn),
    (std::string, white_move),
    (std::string, black_move),
    (std::string, result)
)

BOOST_FUSION_ADAPT_STRUCT(
    loloof64::pgn_game,
    (std::vector<loloof64::pgn_tag>, header),
    (std::vector<loloof64::game_move>, moves)
)

namespace loloof64 {
    namespace qi = boost::spirit::qi;
    namespace ascii = boost::spirit::ascii;
    namespace phoenix = boost::phoenix;

    template <typename Iterator>
    struct pgn_parser : qi::grammar<Iterator, std::vector<pgn_game>, qi::unused_type>
    {
        pgn_parser() : pgn_parser::base_type(games)
        {
            using qi::lexeme;
            using ascii::char_;
            using qi::uint_;
            using qi::alnum;
            using qi::space;
            using qi::omit;
            using qi::eol;
            using qi::lit;

            quoted_string %= lexeme[lit('"') >> *(char_ - '"') >> lit('"')];

            tag %=
                '['
                >> +alnum
                >> omit[+space]
                >> quoted_string
                >> ']'
                >> omit[+eol]
                ;

            header %= +tag;

            move_turn %= qi::string("...") | qi::string(".");

            regular_move %=
                +char_("a-hNBRQK")
                >> +char_("a-h1-8x=NBRQK")
                >> -qi::string("e.p.")
                ;
            castle_move %= qi::string("O-O-O") | qi::string("O-O");
            single_move %=
                (regular_move | castle_move) >> -(char_('+') | char_('#'))
                ;

            result %= qi::string("1-0") | qi::string("0-1") | qi::string("1/2-1/2") | qi::string("*");

            full_move %=
                uint_
                >> move_turn
                >> omit[*space]
                >> single_move
                >> -(omit[+space] >> single_move)
                >> -(omit[+space] >> result)
                ;

            game_description %= full_move
                >> *(omit[*space] >> full_move);

            single_game %=
                -header
                >> game_description
                ;

            games %=
                single_game
                >> *(omit[*(space|eol)] >> single_game)
                ;
        }

        qi::rule<Iterator, pgn_tag(), qi::unused_type> tag;
        qi::rule<Iterator, std::vector<pgn_tag>, qi::unused_type> header;
        qi::rule<Iterator, std::string(), qi::unused_type> quoted_string;

        qi::rule<Iterator, std::string(), qi::unused_type> result;
        qi::rule<Iterator, std::string(), qi::unused_type> regular_move;
        qi::rule<Iterator, std::string(), qi::unused_type> castle_move;
        qi::rule<Iterator, std::string(), qi::unused_type> single_move;
        qi::rule<Iterator, std::string(), qi::unused_type> move_turn;
        qi::rule<Iterator, game_move(), qi::unused_type> full_move;
        qi::rule<Iterator, std::vector<game_move>, qi::unused_type> game_description;

        qi::rule<Iterator, pgn_game, qi::unused_type> single_game;
        qi::rule<Iterator, std::vector<pgn_game>, qi::unused_type> games;
    };
}

我怎么能简单地消耗我无法“预期”的任何角色？我的意思是，我怎么能在我的语法规则中忽略任何我不想要的字符？

出于测试目的：

这里是我的解析器头文件 (pgn_games_extractor.hpp)

#ifndef PGNGAMESEXTRACTOR_HPP
#define PGNGAMESEXTRACTOR_HPP

#include <string>
#include <vector>
#include <fstream>
#include <stdexcept>

namespace loloof64 {

    struct pgn_tag {
        std::string key;
        std::string value;
    };

    struct game_move {
        unsigned move_number;
        std::string move_turn;
        std::string white_move;
        std::string black_move;
        std::string result;
    };

    struct pgn_game {
        std::vector<pgn_tag> header;
        std::vector<game_move> moves;
    };

    class PgnGamesExtractor
    {
        public:
            PgnGamesExtractor(std::string inputFilePath);
            PgnGamesExtractor(std::ifstream &inputFile);
            /*
            Both constructos may throw PgnParsingException (if bad pgn format) and InputFileException (if missing file)
            */
            std::vector<pgn_game> getGames() const { return games; }
            virtual ~PgnGamesExtractor();

        protected:

        private:
            std::vector<pgn_game> games;
            void parseInput(std::ifstream &inputFile);
    };

    class PgnParsingException : public std::runtime_error
    {
    public:
        PgnParsingException(std::string message):     std::runtime_error(message){}
    };

    class InputFileException : public std::runtime_error
    {
    public:
        InputFileException(std::string message) :     std::runtime_error(message){}
    };
}

#endif // PGNGAMESEXTRACTOR_HPP

这是我的解析器源 (pgn_games_extractor.cpp)：

#include "pgn_games_extractor.hpp"

#include <boost/spirit/include/qi.hpp>
#include <boost/spirit/include/phoenix.hpp>
#include <boost/fusion/include/adapt_struct.hpp>

BOOST_FUSION_ADAPT_STRUCT(
    loloof64::pgn_tag,
    (std::string, key),
    (std::string, value)
)

BOOST_FUSION_ADAPT_STRUCT(
    loloof64::game_move,
    (unsigned, move_number),
    (std::string, move_turn),
    (std::string, white_move),
    (std::string, black_move),
    (std::string, result)
)

BOOST_FUSION_ADAPT_STRUCT(
    loloof64::pgn_game,
    (std::vector<loloof64::pgn_tag>, header),
    (std::vector<loloof64::game_move>, moves)
)

namespace loloof64 {
    namespace qi = boost::spirit::qi;
    namespace ascii = boost::spirit::ascii;
    namespace phoenix = boost::phoenix;

    template <typename Iterator>
    struct pgn_parser : qi::grammar<Iterator, std::vector<pgn_game>, qi::unused_type>
    {
        pgn_parser() : pgn_parser::base_type(games)
        {
            using qi::lexeme;
            using ascii::char_;
            using qi::uint_;
            using qi::alnum;
            using qi::space;
            using qi::omit;
            using qi::eol;
            using qi::lit;

            quoted_string %= lexeme[lit('"') >> *(char_ - '"') >> lit('"')];

            tag %=
                '['
                >> +alnum
                >> omit[+space]
                >> quoted_string
                >> ']'
                >> omit[+eol]
                ;

            header %= +tag;

            move_turn %= qi::string("...") | qi::string(".");

            regular_move %=
                +char_("a-hNBRQK")
                >> +char_("a-h1-8x=NBRQK")
                >> -qi::string("e.p.")
                ;
            castle_move %= qi::string("O-O-O") | qi::string("O-O");
            single_move %=
                (regular_move | castle_move) >> -(char_('+') | char_('#'))
                ;

            result %= qi::string("1-0") | qi::string("0-1") | qi::string("1/2-1/2") | qi::string("*");

            full_move %=
                uint_
                >> move_turn
                >> omit[*space]
                >> single_move
                >> -(omit[+space] >> single_move)
                >> -(omit[+space] >> result)
                ;

            game_description %= full_move
                >> *(omit[*space] >> full_move);

            single_game %=
                -header
                >> game_description
                ;

            games %=
                single_game
                >> *(omit[*(space|eol)] >> single_game)
                ;
        }

        qi::rule<Iterator, pgn_tag(), qi::unused_type> tag;
        qi::rule<Iterator, std::vector<pgn_tag>, qi::unused_type> header;
        qi::rule<Iterator, std::string(), qi::unused_type> quoted_string;

        qi::rule<Iterator, std::string(), qi::unused_type> result;
        qi::rule<Iterator, std::string(), qi::unused_type> regular_move;
        qi::rule<Iterator, std::string(), qi::unused_type> castle_move;
        qi::rule<Iterator, std::string(), qi::unused_type> single_move;
        qi::rule<Iterator, std::string(), qi::unused_type> move_turn;
        qi::rule<Iterator, game_move(), qi::unused_type> full_move;
        qi::rule<Iterator, std::vector<game_move>, qi::unused_type> game_description;

        qi::rule<Iterator, pgn_game, qi::unused_type> single_game;
        qi::rule<Iterator, std::vector<pgn_game>, qi::unused_type> games;
    };
}


loloof64::PgnGamesExtractor::PgnGamesExtractor(std::string inputFilePath)
{
    std::ifstream inputFile(inputFilePath);
    parseInput(inputFile);
}

loloof64::PgnGamesExtractor::PgnGamesExtractor(std::ifstream &inputFile)
{
    parseInput(inputFile);
}

loloof64::PgnGamesExtractor::~PgnGamesExtractor()
{
    //dtor
}

void loloof64::PgnGamesExtractor::parseInput(std::ifstream &inputFile)
{
    using namespace std;

    if (! inputFile) throw InputFileException("File does not exist !");

    string content("");
    getline(inputFile, content, (char) inputFile.eof());

    if (inputFile.fail() || inputFile.bad()) throw new     InputFileException("Could not read the input file !");

    loloof64::pgn_parser<string::const_iterator> parser;
    std::vector<loloof64::pgn_game> temp_games;

    string::const_iterator iter = content.begin();
    string::const_iterator end = content.end();

    bool success = boost::spirit::qi::phrase_parse(iter, end, parser, boost::spirit::qi::eol, temp_games);

    if (success && iter == end)
    {
        games = temp_games;
    }
    else
    {
        string error_fragment(iter, end);
        string error_message("");

        error_message = "Failed to parse the input at :'" + error_fragment + "' !";

        throw PgnParsingException(error_message);
    }
}

我问这个问题是因为我无法解析以下 pgn ：ScotchGambitPgn.zip。我认为这是因为此文件的编码问题。

我正在使用 Spirit 2 和 C++ 11 (Gnu)

Answer 1

根据要求进行简单的 X3 翻译。

• 更少的代码行（10 行）
• 编译时间从 7.4 秒缩短到 3.6 秒（clang）
• 编译时间从 11.4s 缩短到 6.0s (gcc5)
• 运行时间从 0.80 秒缩短到 0.55 秒（clang 和 gcc）

输出是相同的（完全一样）。

Live On Coliru

//#define BOOST_SPIRIT_DEBUG
#ifndef PGNGAMESEXTRACTOR_HPP
#define PGNGAMESEXTRACTOR_HPP

#include <string>
#include <vector>
#include <fstream>
#include <stdexcept>

namespace loloof64 {

struct pgn_tag {
    std::string key;
    std::string value;
};

struct game_move {
    unsigned move_number;
    std::string white_move;
    std::string black_move;
    enum result_t { white_won, black_won, draw, undecided } result;
};

struct pgn_game {
    std::vector<pgn_tag> header;
    std::vector<game_move> moves;
};

class PgnGamesExtractor {
  public:
    PgnGamesExtractor(std::string inputFilePath);
    PgnGamesExtractor(std::istream &inputFile);
    /*
    Both constructos may throw PgnParsingException (if bad pgn format) and InputFileException (if missing file)
    */
    std::vector<pgn_game> getGames() const { return games; }
    virtual ~PgnGamesExtractor();

  protected:
  private:
    std::vector<pgn_game> games;
    void parseInput(std::istream &inputFile);
};

class PgnParsingException : public virtual std::runtime_error {
  public:
    PgnParsingException(std::string message) : std::runtime_error(message) {}
};

class InputFileException : public virtual std::runtime_error {
  public:
    InputFileException(std::string message) : std::runtime_error(message) {}
};
}

#endif // PGNGAMESEXTRACTOR_HPP

#include <boost/spirit/home/x3.hpp>
#include <boost/spirit/include/support_istream_iterator.hpp>
#include <boost/fusion/include/adapt_struct.hpp>

BOOST_FUSION_ADAPT_STRUCT(loloof64::pgn_tag, key, value)
BOOST_FUSION_ADAPT_STRUCT(loloof64::game_move, move_number, white_move, black_move, result)
BOOST_FUSION_ADAPT_STRUCT(loloof64::pgn_game, header, moves)

namespace loloof64 {
    namespace pgn_parser {
        using namespace boost::spirit::x3;

        static std::string const no_move;
        static auto const result = []{
            symbols<game_move::result_t> table;
            table.add
                ("1-0",     game_move::white_won)
                ("0-1",     game_move::black_won)
                ("1/2-1/2", game_move::draw)
                ("*",       game_move::undecided);
            return table;
        }();

        static auto const quoted_string    = lexeme['"' >> *~char_('"') >> '"'];
        static auto const tag              = '[' >> +alnum >> quoted_string >> ']';
        static auto const header           = +tag;
        static auto const regular_move     = as_parser("O-O-O") | "O-O" | (+char_("a-hNBRQK") >> +char_("a-h1-8x=NBRQK") >> -lit("e.p."));
        static auto const single_move      = rule<struct single_move_, std::string> { "single_move" }
                                           = raw [ lexeme [ regular_move >> -char_("+#")] ];
        static auto const full_move        = rule<struct full_move_, game_move> { "full_move" }
                                     = uint_ 
            >> (lexeme["..." >> attr(no_move)] | "." >> single_move) 
            >> (single_move | attr(no_move))
            >> -result;

        static auto const game_description = +full_move;
        static auto const single_game      = rule<struct single_game_, pgn_game> { "single_game" }
                                           = -header >> game_description;
        static auto const games            = *single_game;
    }

}

loloof64::PgnGamesExtractor::PgnGamesExtractor(std::string inputFilePath) {
    std::ifstream inputFile(inputFilePath);
    parseInput(inputFile);
}

loloof64::PgnGamesExtractor::PgnGamesExtractor(std::istream &inputFile) { parseInput(inputFile); }

loloof64::PgnGamesExtractor::~PgnGamesExtractor() {
    // dtor
}

void loloof64::PgnGamesExtractor::parseInput(std::istream &inputFile) {
    if (inputFile.fail() || inputFile.bad())
        throw new InputFileException("Could not read the input file !");

    typedef boost::spirit::istream_iterator It;
    std::vector<loloof64::pgn_game> temp_games;

    It iter(inputFile >> std::noskipws), end;

    bool success = boost::spirit::x3::phrase_parse(iter, end, pgn_parser::games, boost::spirit::x3::space, temp_games);

    if (success && iter == end) {
        games.swap(temp_games);
    } else {
        std::string error_fragment(iter, end);
        throw PgnParsingException("Failed to parse the input at :'" + error_fragment + "' !");
    }
}

#include <iostream>

int main() {
    loloof64::PgnGamesExtractor pge("ScotchGambit.pgn");
    std::cout << "Parsed " << pge.getGames().size() << " games\n";
    for (auto& g : pge.getGames())
        for (auto& m : g.moves)
            std::cout << m.move_number << ".\t" << m.white_move << "\t" << m.black_move << "\n";
}

Answer 2

对于它的价值，这里大大简化了：

Live On Coliru

//#define BOOST_SPIRIT_DEBUG
#ifndef PGNGAMESEXTRACTOR_HPP
#define PGNGAMESEXTRACTOR_HPP

#include <string>
#include <vector>
#include <fstream>
#include <stdexcept>

namespace loloof64 {

struct pgn_tag {
    std::string key;
    std::string value;
};

struct game_move {
    unsigned move_number;
    std::string white_move;
    std::string black_move;
    enum result_t { white_won, black_won, draw, undecided } result;
};

struct pgn_game {
    std::vector<pgn_tag> header;
    std::vector<game_move> moves;
};

class PgnGamesExtractor {
  public:
    PgnGamesExtractor(std::string inputFilePath);
    PgnGamesExtractor(std::istream &inputFile);
    /*
    Both constructos may throw PgnParsingException (if bad pgn format) and InputFileException (if missing file)
    */
    std::vector<pgn_game> getGames() const { return games; }
    virtual ~PgnGamesExtractor();

  protected:
  private:
    std::vector<pgn_game> games;
    void parseInput(std::istream &inputFile);
};

class PgnParsingException : public virtual std::runtime_error {
  public:
    PgnParsingException(std::string message) : std::runtime_error(message) {}
};

class InputFileException : public virtual std::runtime_error {
  public:
    InputFileException(std::string message) : std::runtime_error(message) {}
};
}

#endif // PGNGAMESEXTRACTOR_HPP

#include <boost/spirit/include/qi.hpp>
#include <boost/fusion/include/adapt_struct.hpp>

BOOST_FUSION_ADAPT_STRUCT(loloof64::pgn_tag, key, value)
BOOST_FUSION_ADAPT_STRUCT(loloof64::game_move, move_number, white_move, black_move, result)
BOOST_FUSION_ADAPT_STRUCT(loloof64::pgn_game, header, moves)

namespace loloof64 {
namespace qi = boost::spirit::qi;

template <typename Iterator> struct pgn_parser : qi::grammar<Iterator, std::vector<pgn_game>, qi::space_type> {
    pgn_parser() : pgn_parser::base_type(games) {
        using namespace qi;

        const std::string no_move;
        result.add
            ("1-0",     game_move::white_won)
            ("0-1",     game_move::black_won)
            ("1/2-1/2", game_move::draw)
            ("*",       game_move::undecided);

        quoted_string    = '"' >> *~char_('"') >> '"';
        tag              = '[' >> +alnum >> quoted_string >> ']';
        header           = +tag;
        regular_move     = lit("O-O-O") | "O-O" | (+char_("a-hNBRQK") >> +char_("a-h1-8x=NBRQK") >> -lit("e.p."));
        single_move      = raw [ regular_move >> -char_("+#") ];
        full_move        = uint_ 
            >> (lexeme["..." >> attr(no_move)] | "." >> single_move) 
            >> (single_move | attr(no_move))
            >> -result;

        game_description = +full_move;
        single_game      = -header >> game_description;
        games            = *single_game;

        BOOST_SPIRIT_DEBUG_NODES(
                    (tag)(header)(quoted_string)(regular_move)(single_move)
                    (full_move)(game_description)(single_game)(games)
                )
    }

  private:
    qi::rule<Iterator, pgn_tag(),              qi::space_type> tag;
    qi::rule<Iterator, std::vector<pgn_tag>,   qi::space_type> header;

    qi::rule<Iterator, game_move(),            qi::space_type> full_move;
    qi::rule<Iterator, std::vector<game_move>, qi::space_type> game_description;

    qi::rule<Iterator, pgn_game,               qi::space_type> single_game;
    qi::rule<Iterator, std::vector<pgn_game>,  qi::space_type> games;

    // lexemes
    qi::symbols<char, game_move::result_t> result;
    qi::rule<Iterator, std::string()> quoted_string;
    qi::rule<Iterator> regular_move;
    qi::rule<Iterator, std::string()> single_move;
};
}

loloof64::PgnGamesExtractor::PgnGamesExtractor(std::string inputFilePath) {
    std::ifstream inputFile(inputFilePath);
    parseInput(inputFile);
}

loloof64::PgnGamesExtractor::PgnGamesExtractor(std::istream &inputFile) { parseInput(inputFile); }

loloof64::PgnGamesExtractor::~PgnGamesExtractor() {
    // dtor
}

void loloof64::PgnGamesExtractor::parseInput(std::istream &inputFile) {
    if (inputFile.fail() || inputFile.bad())
        throw new InputFileException("Could not read the input file !");

    typedef boost::spirit::istream_iterator It;
    loloof64::pgn_parser<It> parser;
    std::vector<loloof64::pgn_game> temp_games;

    It iter(inputFile >> std::noskipws), end;

    bool success = boost::spirit::qi::phrase_parse(iter, end, parser, boost::spirit::qi::space, temp_games);

    if (success && iter == end) {
        games.swap(temp_games);
    } else {
        std::string error_fragment(iter, end);
        throw PgnParsingException("Failed to parse the input at :'" + error_fragment + "' !");
    }
}

int main() {
    loloof64::PgnGamesExtractor pge(std::cin); // "ScotchGambit.pgn"
    std::cout << "Parsed " << pge.getGames().size() << " games\n";
    for (auto& g : pge.getGames())
        for (auto& m : g.moves)
            std::cout << m.move_number << ".\t" << m.white_move << "\t" << m.black_move << "\n";
}

注意事项：

• 不要读取内存中的完整文件 (boost::spirit::istream_iterator)
• 不要手动跳过（使用跳过器）
• 不要明确的词位 (Boost spirit skipper issues)
• 如果不需要，请勿使用 %=
• 不要合成不需要的属性（使用raw[]）
• 将 move 的可选部分视为可选部分，不要存储不对称的魔法标志，如“...”（查找 no_move）
• 不要过于具体（使用istream& 而不是ifstream&）

可能我忘记了其他一些事情。输出是例如

Parsed 6166 games
1.  e4  e5
2.  Nf3 Nc6
3.  d4  exd4
4.  Bc4 Qf6
5.  O-O d6
6.  Ng5 Nh6
7.  f4  Be7
8.  e5  Qg6
9.  exd6    cxd6
10. c3  dxc3
11. Nxc3    O-O
12. Nd5 Bd7
13. Rf3 Bg4
14. Bd3 Bxf3
15. Qxf3    f5
16. Bc4 Kh8
17. Nxe7    Nxe7
18. Qxb7    Qf6
19. Be3 Rfb8
20. Qd7 Rd8
21. Qb7 d5
22. Bb3 Nc6
23. Bxd5    Nd4
24. Rd1 Ne2+
25. Kf1 Rab8
26. Qxa7    Rxb2
27. Ne6 Qxe6
28. Bxe6    Rxd1+
29. Kf2 
1.  e4  e5
2.  Nf3 Nc6
3.  d4  exd4
4.  Bc4 Bc5
5.  Ng5 Ne5
6.  Bxf7+   Nxf7
7.  Nxf7    Bb4+
8.  c3  dxc3
9.  bxc3    Bxc3+
10. Nxc3    Kxf7
11. Qd5+    Kf8
12. Ba3+    d6
13. e5  Qg5
14. exd6    Qxd5

Answer 3

确实问题出在维罗妮卡身上。或者，实际上，它与 Ver?nica 一起使用。在哪里 ？是代码单元<93> - 缺少代码页/编码信息可能意味着什么。

您正在使用 ascii::char，这需要 7 位字符。

通过更改轻松修复它

using ascii::char_;

进入

using qi::char_;