C++ boost:：spirit:qi:：rule或包含qi:：rule作为解析结果的结构

我试图做的是在运行时从ABNF语法文件创建一个解析器。我已经在qi:：语法中实现了所有ABNF规则，如下所示：

typedef /*qi::rule or struct containing qi::rule*/ parserRule

    [...] //all other ABNF rules according to RFC 5234

    rule =
            (
                    rulename[qi::_a = qi::_1] >>
                    definedAs >>
                    elements[qi::_b = qi::_1] >>
                    cNl
            )[qi::_val = px::bind(&AbnfParserFactory::fromRule, &factory, qi::_a, qi::_b)];


    rulelist =
            +(
                    rule[px::push_back(qi::_a, qi::_1)] |
                    (*cWsp >> cNl)
             ) >>
             eps[qi::_val = px::bind(&AbnfParserFactory::fromRulelist, &factory, qi::_a)];


qi::rule<Iterator, std::map<std::string, parserRule>(), qi::locals<std::vector<parserRule> > >  rulelist;
qi::rule<Iterator, parserRule(), qi::locals<std::string>, qi::locals<parserRule> >              rule;
[...] // all other ABNF rules

问题是关于

parserRule

的类型

如果我使用qi:：rule作为类型（就像我通常打算的那样），我将丢失在

ParserFactory

中分配的所有规则名称（就像

fromRule

中的规则名称）。我猜这是由spirit内部工作的方式造成的（

=

操作符总是创建一个新的未命名规则。而

=

用于分配px:：bind函数结果）

但是，如果我试图将我的qi:：rule封装到一个结构中以避免这个问题，我将无法再使用spirit调试编译代码。以下是我尝试过的：

typedef qi::rule<std::string::const_iterator, std::string()> FactoryRuleType;
struct parserRule
{
    FactoryRuleType mRule;
};

BOOST_FUSION_ADAPT_STRUCT(
 parserRule,
(FactoryRuleType, mRule)
)

[...] //rule definitions like above

debug(rule);
debug(rulelist);
[...] //debug all other rules

typedef qi:：rule FactoryRuleType；
结构分析器
{
FactoryRuleType规则；
};
增强融合适应结构(
帕斯瑞尔，
（FactoryRuleType，mRule）
)
[…]//如上所述的规则定义
调试（规则）；
调试（规则列表）；
[…]//调试所有其他规则

这将给我一个编译错误的负载（这是一个很长的方式张贴在这里）。我花了好几天的时间试图解决这个问题，但没有任何运气。我希望我提到了足够的细节

感谢您的帮助

编译输出摘录：

/usr/include/boost/proto/operators.hpp:295:9: note:   template argument deduction/substitution failed:
/usr/include/boost/proto/operators.hpp: In substitution of ‘template<class Left, class Right> const typename boost::proto::detail::enable_binary<boost::proto::domainns_::deduce_domain, boost::proto::detail::not_a_grammar, boost::mpl::or_<boost::proto::is_extension<Arg>, boost::proto::is_extension<Right> >, boost::proto::tagns_::tag::shift_left, Left&, Right&>::type boost::proto::exprns_::operator<<(Left&, Right&) [with Left = std::basic_ostream<char>; Right = const boost::spirit::qi::reference<const boost::spirit::qi::rule<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char> >, std::basic_string<char>()> >]’:
/usr/include/boost/spirit/home/support/attributes.hpp:1226:17:   required from ‘static void boost::spirit::traits::print_attribute_debug<Out, T, Enable>::call_impl3(Out&, const T_&, mpl_::false_) [with T_ = boost::spirit::qi::reference<const boost::spirit::qi::rule<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char> >, std::basic_string<char>()> >; Out = std::basic_ostream<char>; T = boost::spirit::qi::reference<const boost::spirit::qi::rule<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char> >, std::basic_string<char>()> >; Enable = void; mpl_::false_ = mpl_::bool_<false>]’
/usr/include/boost/spirit/home/support/attributes.hpp:1242:67:   required from ‘static void boost::spirit::traits::print_attribute_debug<Out, T, Enable>::call_impl2(Out&, const T_&, mpl_::false_) [with T_ = boost::spirit::qi::reference<const boost::spirit::qi::rule<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char> >, std::basic_string<char>()> >; Out = std::basic_ostream<char>; T = boost::spirit::qi::reference<const boost::spirit::qi::rule<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char> >, std::basic_string<char>()> >; Enable = void; mpl_::false_ = mpl_::bool_<false>]’
/usr/include/boost/spirit/home/support/attributes.hpp:1277:52:   required from ‘static void boost::spirit::traits::print_attribute_debug<Out, T, Enable>::call_impl(Out&, const T_&, mpl_::true_) [with T_ = boost::spirit::qi::reference<const boost::spirit::qi::rule<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char> >, std::basic_string<char>()> >; Out = std::basic_ostream<char>; T = boost::spirit::qi::reference<const boost::spirit::qi::rule<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char> >, std::basic_string<char>()> >; Enable = void; mpl_::true_ = mpl_::bool_<true>]’
/usr/include/boost/spirit/home/support/attributes.hpp:1283:52:   required from ‘static void boost::spirit::traits::print_attribute_debug<Out, T, Enable>::call(Out&, const T&) [with Out = std::basic_ostream<char>; T = boost::spirit::qi::reference<const boost::spirit::qi::rule<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char> >, std::basic_string<char>()> >; Enable = void]’
/usr/include/boost/spirit/home/support/attributes.hpp:1303:53:   required from ‘void boost::spirit::traits::print_attribute(Out&, const T&) [with Out = std::basic_ostream<char>; T = boost::spirit::qi::reference<const boost::spirit::qi::rule<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char> >, std::basic_string<char>()> >]’
/usr/include/boost/spirit/home/support/attributes.hpp:1196:57:   [ skipping 34 instantiation contexts, use -ftemplate-backtrace-limit=0 to disable ]
/usr/include/boost/function/function_template.hpp:722:7:   required from ‘boost::function4<R, T1, T2, T3, T4>::function4(Functor, typename boost::enable_if_c<boost::type_traits::ice_not<boost::is_integral<Functor>::value>::value, int>::type) [with Functor = boost::spirit::qi::debug_handler<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char> >, boost::spirit::context<boost::fusion::cons<FactoryReturnType&, boost::fusion::nil>, boost::fusion::vector0<> >, boost::spirit::unused_type, boost::spirit::qi::simple_trace>; R = bool; T0 = __gnu_cxx::__normal_iterator<const char*, std::basic_string<char> >&; T1 = const __gnu_cxx::__normal_iterator<const char*, std::basic_string<char> >&; T2 = boost::spirit::context<boost::fusion::cons<FactoryReturnType&, boost::fusion::nil>, boost::fusion::vector0<> >&; T3 = const boost::spirit::unused_type&; typename boost::enable_if_c<boost::type_traits::ice_not<boost::is_integral<Functor>::value>::value, int>::type = int]’
/usr/include/boost/function/function_template.hpp:1069:16:   required from ‘boost::function<R(T0, T1, T2, T3)>::function(Functor, typename boost::enable_if_c<boost::type_traits::ice_not<boost::is_integral<Functor>::value>::value, int>::type) [with Functor = boost::spirit::qi::debug_handler<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char> >, boost::spirit::context<boost::fusion::cons<FactoryReturnType&, boost::fusion::nil>, boost::fusion::vector0<> >, boost::spirit::unused_type, boost::spirit::qi::simple_trace>; R = bool; T0 = __gnu_cxx::__normal_iterator<const char*, std::basic_string<char> >&; T1 = const __gnu_cxx::__normal_iterator<const char*, std::basic_string<char> >&; T2 = boost::spirit::context<boost::fusion::cons<FactoryReturnType&, boost::fusion::nil>, boost::fusion::vector0<> >&; T3 = const boost::spirit::unused_type&; typename boost::enable_if_c<boost::type_traits::ice_not<boost::is_integral<Functor>::value>::value, int>::type = int]’
/usr/include/boost/function/function_template.hpp:1124:5:   required from ‘typename boost::enable_if_c<boost::type_traits::ice_not<boost::is_integral<Functor>::value>::value, boost::function<R(T0, T1, T2, T3)>&>::type boost::function<R(T0, T1, T2, T3)>::operator=(Functor) [with Functor = boost::spirit::qi::debug_handler<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char> >, boost::spirit::context<boost::fusion::cons<FactoryReturnType&, boost::fusion::nil>, boost::fusion::vector0<> >, boost::spirit::unused_type, boost::spirit::qi::simple_trace>; R = bool; T0 = __gnu_cxx::__normal_iterator<const char*, std::basic_string<char> >&; T1 = const __gnu_cxx::__normal_iterator<const char*, std::basic_string<char> >&; T2 = boost::spirit::context<boost::fusion::cons<FactoryReturnType&, boost::fusion::nil>, boost::fusion::vector0<> >&; T3 = const boost::spirit::unused_type&; typename boost::enable_if_c<boost::type_traits::ice_not<boost::is_integral<Functor>::value>::value, boost::function<R(T0, T1, T2, T3)>&>::type = boost::function<bool(__gnu_cxx::__normal_iterator<const char*, std::basic_string<char> >&, const __gnu_cxx::__normal_iterator<const char*, std::basic_string<char> >&, boost::spirit::context<boost::fusion::cons<FactoryReturnType&, boost::fusion::nil>, boost::fusion::vector0<> >&, const boost::spirit::unused_type&)>&]’
/usr/include/boost/spirit/home/qi/nonterminal/debug_handler.hpp:122:13:   required from ‘void boost::spirit::qi::debug(boost::spirit::qi::rule<Iterator, T1, T2, T3, T4>&) [with Iterator = __gnu_cxx::__normal_iterator<const char*, std::basic_string<char> >; T1 = FactoryReturnType(); T2 = boost::spirit::unused_type; T3 = boost::spirit::unused_type; T4 = boost::spirit::unused_type]’
../src/AbnfReader.hpp:350:14:   required from ‘AbnfRules<Iterator>::AbnfRules() [with Iterator = __gnu_cxx::__normal_iterator<const char*, std::basic_string<char> >]’
../src/AbnfReader.cpp:27:12:   required from here
/usr/include/boost/proto/operators.hpp:295:9: error: no type named ‘type’ in ‘struct boost::proto::detail::enable_binary<boost::proto::domainns_::deduce_domain, boost::proto::detail::not_a_grammar, boost::mpl::or_<boost::proto::is_extension<std::basic_ostream<char> >, boost::proto::is_extension<const boost::spirit::qi::reference<const boost::spirit::qi::rule<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char> >, std::basic_string<char>()> > >, mpl_::bool_<false>, mpl_::bool_<false>, mpl_::bool_<false> >, boost::proto::tagns_::tag::shift_left, std::basic_ostream<char>&, const boost::spirit::qi::reference<const boost::spirit::qi::rule<__gnu_cxx::__normal_iterator<const char*, std::basic_string<char> >, std::basic_string<char>()> >&>’
make: *** [src/AbnfReader.o] Error 1

/usr/include/boost/proto/operators.hpp:295:9:注意：模板参数推断/替换失败：
/usr/include/boost/proto/operators.hpp：用“模板const typename boost:：proto:：detail:：enable_binary:：type boost:：proto:：exprns_216;：：operator”来代替“模板const typename boost:：proto:：detail:：enable_binary:：type boost:：proto:：exprns_216;:：operator”这里有

单元素自适应结构会带来问题，请参见：[链接]

调试信息需要调试打印特性的专门化（可以追溯到
ostream
streaming）。显然，
qi:：rule
没有这样做。所以，要么加上这个

也许，只是也许你可以让包含的struct iostream能够避免它（但我担心融合适应可能会优先考虑。这是一次尝试）


是的，你是对的。我必须在运行时动态编写语法。为了确保这是可能的，我已经编写了一系列测试代码片段，它们按照预期的方式工作


直言不讳地说：精神不是实现这一目标的工具。Spirit是一个从“praser表达式”（表达式模板）生成静态编译语法的工具。整个目的是在编译时使用静态多态性并进行充分优化。我建议您创建一组运行时多态解析器组件（反过来，您可以使用Spirit:）来实现），并用它们来编写动态语法

一种可能的中间立场是使用
qi:：lazy
和一组预定义的不可变“atom”规则（因此不是动态组合的），并通过引用使用这些“atom”规则来组合解析器

基本上，只要您不尝试动态组合表达式模板（而是现成的类型擦除的非终端），您就可以了

如果你还需要更多，你很快就会到达乌兰巴托。有些时候，您可以使用
boost:：proto:：deep_copy
奋力拼搏，但这有其局限性

嗯，这很尴尬。当我试图编写一个像sehe建议的SSCCE时，我发现我的方法实际上一直都在工作。为了解决这个问题，我经历了很多麻烦…：C

这是一个我试图做的工作示例。虽然它有效，但这种行为仍然有点奇怪，这就是我认为它不能以这种方式工作的原因

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

namespace qi = boost::spirit::qi;
namespace px = boost::phoenix;
namespace ascii = boost::spirit::ascii;

typedef qi::rule<std::string::const_iterator, std::string()> parserRule;


namespace std
{
std::ostream& operator<<(std::ostream& stream, const parserRule& val);
}
std::ostream& std::operator<<(std::ostream& stream, const parserRule& val)
{
    stream << "RULE( " << val.name();
    stream << " )";
    return stream;
}

class Factory
{
public:
    Factory(){}
    parserRule createParser(std::string str)
    {
        parserRule r;
        r = qi::char_(str);
        r.name("FactoryRule");
        std::cout << r.name() << " now parses >" + str + "<" << std::end;
        return r;
    }
};

template <typename Iterator>
struct TestGrammar : qi::grammar<Iterator, parserRule()>
{

    TestGrammar() : TestGrammar::base_type(start, "Test grammar")
    {
        start = stringRule.alias();
        stringRule =    (
                ascii::char_("'") >>
                *(ascii::char_ - ascii::char_("'"))[qi::_a += qi::_1] >>
                ascii::char_("'")
        )[qi::_val = px::bind(&Factory::createParser, &factory, qi::_a)];

        start.name("Start");
        stringRule.name("StringRule");

        qi::debug(start);       // shows "RULE( unnamed-rule )"
        qi::debug(stringRule);  // shows "RULE( unnamed-rule )"
    }

    qi::rule<Iterator, parserRule() > start;
    qi::rule<Iterator, parserRule(), qi::locals<std::string> > stringRule;
    Factory factory;
};

int main()
{
    typedef std::string::const_iterator iterator_type;
    typedef TestGrammar<iterator_type> TGrammar;


    TGrammar test_parser;

    std::string test = "parse THIS!";
    std::string input = "'"+test+"'";
    parserRule result;

    std::string::const_iterator iter = input.begin();
    std::string::const_iterator end = input.end();

    bool r = parse(iter, end, test_parser, result);

    if (r && iter == end)
    {
        std::cout << "-------------------------\n";
        std::cout << "1st Parsing succeeded\n";
        std::cout << "-------------------------\n";
    }
    else
    {
        std::string rest(iter, end);
        std::cout << "-------------------------\n";
        std::cout << "1st Parsing failed\n";
        std::cout << "stopped at: \"" << rest << "\"\n";
        std::cout << "-------------------------\n";
    }

    iterator_type first(test.begin()), last(test.end());

    qi::debug(result); //shows correct rule name
    r = qi::phrase_parse(first, last, result, boost::spirit::ascii::space);

    if (r && iter == end)
    {
        std::cout << "-------------------------\n";
        std::cout << "2nd Parsing succeeded\n";
        std::cout << "-------------------------\n";
    }
    else
    {
        std::string rest(first, last);
        std::cout << "-------------------------\n";
        std::cout << "2nd Parsing failed\n";
        std::cout << "stopped at: \"" << rest << "\"\n";
        std::cout << "-------------------------\n";
    }
}

#包括
#包括
名称空间qi=boost:：spirit:：qi；
名称空间px=boost:：phoenix；
名称空间ascii=boost:：spirit:：ascii；
typedef qi:：rule parserRule；
名称空间标准
{
std:：ostream&operatorI我不知道你想说什么。你能用一个简洁的方式演示你的问题吗？另外，我有一种感觉，你想动态地编写语法。这条路充满了危险，因为Boost Proto/Boost Phoenix的表达式模板不是为值语义设计的（他们宁愿只作为临时工生活）。您可以在我的答案中搜索关键字
deep\u copy
，来了解您将遇到的许多问题。是的，您是对的。我必须在运行时动态编写语法。为了确保这一点可行，我已经编写了一系列测试片段，这些片段按照预期工作。因此我认为我的方法是可行的（虽然这可能不是最好的）。我会看看你的答案，如果我有时间的话，试着整理一下我的问题。谢谢
#include <boost/spirit/include/qi.hpp>
#include <boost/spirit/include/phoenix.hpp>

namespace qi = boost::spirit::qi;
namespace px = boost::phoenix;
namespace ascii = boost::spirit::ascii;

typedef qi::rule<std::string::const_iterator, std::string()> parserRule;


namespace std
{
std::ostream& operator<<(std::ostream& stream, const parserRule& val);
}
std::ostream& std::operator<<(std::ostream& stream, const parserRule& val)
{
    stream << "RULE( " << val.name();
    stream << " )";
    return stream;
}

class Factory
{
public:
    Factory(){}
    parserRule createParser(std::string str)
    {
        parserRule r;
        r = qi::char_(str);
        r.name("FactoryRule");
        std::cout << r.name() << " now parses >" + str + "<" << std::end;
        return r;
    }
};

template <typename Iterator>
struct TestGrammar : qi::grammar<Iterator, parserRule()>
{

    TestGrammar() : TestGrammar::base_type(start, "Test grammar")
    {
        start = stringRule.alias();
        stringRule =    (
                ascii::char_("'") >>
                *(ascii::char_ - ascii::char_("'"))[qi::_a += qi::_1] >>
                ascii::char_("'")
        )[qi::_val = px::bind(&Factory::createParser, &factory, qi::_a)];

        start.name("Start");
        stringRule.name("StringRule");

        qi::debug(start);       // shows "RULE( unnamed-rule )"
        qi::debug(stringRule);  // shows "RULE( unnamed-rule )"
    }

    qi::rule<Iterator, parserRule() > start;
    qi::rule<Iterator, parserRule(), qi::locals<std::string> > stringRule;
    Factory factory;
};

int main()
{
    typedef std::string::const_iterator iterator_type;
    typedef TestGrammar<iterator_type> TGrammar;


    TGrammar test_parser;

    std::string test = "parse THIS!";
    std::string input = "'"+test+"'";
    parserRule result;

    std::string::const_iterator iter = input.begin();
    std::string::const_iterator end = input.end();

    bool r = parse(iter, end, test_parser, result);

    if (r && iter == end)
    {
        std::cout << "-------------------------\n";
        std::cout << "1st Parsing succeeded\n";
        std::cout << "-------------------------\n";
    }
    else
    {
        std::string rest(iter, end);
        std::cout << "-------------------------\n";
        std::cout << "1st Parsing failed\n";
        std::cout << "stopped at: \"" << rest << "\"\n";
        std::cout << "-------------------------\n";
    }

    iterator_type first(test.begin()), last(test.end());

    qi::debug(result); //shows correct rule name
    r = qi::phrase_parse(first, last, result, boost::spirit::ascii::space);

    if (r && iter == end)
    {
        std::cout << "-------------------------\n";
        std::cout << "2nd Parsing succeeded\n";
        std::cout << "-------------------------\n";
    }
    else
    {
        std::string rest(first, last);
        std::cout << "-------------------------\n";
        std::cout << "2nd Parsing failed\n";
        std::cout << "stopped at: \"" << rest << "\"\n";
        std::cout << "-------------------------\n";
    }
}

FactoryRule now parses >parse THIS!<
<Start>
  <try>'parse THIS!'</try>
  <StringRule>
    <try>'parse THIS!'</try>
    <success></success>
    <attributes>[[RULE( unnamed-rule )]]</attributes><locals>(parse THIS!)</locals>
  </StringRule>
  <success></success>
  <attributes>[[RULE( unnamed-rule )]]</attributes>
</Start>
-------------------------
1st Parsing succeeded
-------------------------
<FactoryRule>
  <try>parse THIS!</try>
  <success>arse THIS!</success>
  <attributes>[[p]]</attributes>
</FactoryRule>
-------------------------
2nd Parsing succeeded
-------------------------