我的目标是让qi::grammar返回一个属性。尽管如此，我在使用spirit::lexer时遇到了很大困难。
我希望使用下面给定的语法，如果我用spirit::qi::parse(begin, end, grammar, output);调用它，那么struct ident output将具有解析的lexeme的内容。
错误似乎主要来自这一行：start %= lexer.identifier;
g++ -g -c -O0 -Wall -DBOOST_SPIRIT_DEBUG -DBOOST_SPIRIT_LEXERTL_DEBUG -DBOOST_SPIRIT_USE_PHOENIX_V3 -DBOOST_SPIRIT_ACTIONS_ALLOW_ATTR_COMPAT reduced.cpp
#include <boost/fusion/include/adapt_struct.hpp>
#include <boost/spirit/home/lex.hpp>
#include <boost/spirit/home/lex/lexer/lexertl/lexer.hpp>
#include <boost/spirit/home/qi.hpp>
namespace spirit = boost::spirit;
struct ident {
std::string value;
};
BOOST_FUSION_ADAPT_STRUCT(ident,
(std::string, value)
)
struct my_lexer : spirit::lex::lexer< spirit::lex::lexertl::actor_lexer<> > {
spirit::lex::token_def<std::string> identifier;
};
struct my_grammar : spirit::qi::grammar<my_lexer::iterator_type, ident()> {
my_grammar(const my_lexer & lexer) : my_grammar::base_type(start) {
start %= lexer.identifier;
}
spirit::qi::rule<my_lexer::iterator_type, ident()> start;
};
In file included from ../reduced-example/reduced.cpp:3:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex.hpp:13:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex/lexer.hpp:14:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex/lexer/token_def.hpp:20:
/home/wlynch/Boost/1.47.0/include/boost/spirit/home/qi/detail/assign_to.hpp:38:24: error: no matching constructor for initialization of 'ident'
attr = Attribute(first, last);
^ ~~~~~~~~~~~
/home/wlynch/Boost/1.47.0/include/boost/spirit/home/qi/detail/assign_to.hpp:94:13: note: in instantiation of member function 'boost::spirit::traits::assign_to_attribute_from_iterators<ident, char const *,
void>::call' requested here
call(first, last, attr);
^
In file included from ../reduced-example/reduced.cpp:4:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex/lexer/lexertl/lexer.hpp:20:
/home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex/lexer/lexertl/token.hpp:530:13: note: in instantiation of function template specialization 'boost::spirit::traits::assign_to<char const *, ident>'
requested here
spirit::traits::assign_to(t.value().begin(), t.value().end(), attr);
^
In file included from ../reduced-example/reduced.cpp:3:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex.hpp:13:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex/lexer.hpp:14:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex/lexer/token_def.hpp:20:
/home/wlynch/Boost/1.47.0/include/boost/spirit/home/qi/detail/assign_to.hpp:330:59: note: in instantiation of member function 'boost::spirit::traits::assign_to_attribute_from_value<ident,
boost::spirit::lex::lexertl::token<char const *, boost::mpl::vector0<mpl_::na>, mpl_::bool_<1>, unsigned long>, void>::call' requested here
assign_to_attribute_from_value<Attribute, T>::call(val, attr);
^
/home/wlynch/Boost/1.47.0/include/boost/spirit/home/qi/detail/assign_to.hpp:353:9: note: in instantiation of function template specialization
'boost::spirit::traits::detail::assign_to<boost::spirit::lex::lexertl::token<char const *, boost::mpl::vector0<mpl_::na>, mpl_::bool_<1>, unsigned long>, ident>' requested here
detail::assign_to(val, attr, is_not_wrapped_container());
^
In file included from ../reduced-example/reduced.cpp:3:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex.hpp:13:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex/lexer.hpp:14:
/home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex/lexer/token_def.hpp:106:21: note: in instantiation of function template specialization
'boost::spirit::traits::assign_to<boost::spirit::lex::lexertl::token<char const *, boost::mpl::vector0<mpl_::na>, mpl_::bool_<1>, unsigned long>, ident>' requested here
spirit::traits::assign_to(t, attr);
^
In file included from ../reduced-example/reduced.cpp:3:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex.hpp:13:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex/lexer.hpp:14:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex/lexer/token_def.hpp:21:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex/reference.hpp:16:
/home/wlynch/Boost/1.47.0/include/boost/spirit/home/qi/reference.hpp:43:20: note: (skipping 5 contexts in backtrace; use -ftemplate-backtrace-limit=0 to see all)
return ref.get().parse(first, last, context, skipper, attr);
^
In file included from ../reduced-example/reduced.cpp:3:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex.hpp:15:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex/tokenize_and_parse.hpp:15:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/qi/nonterminal/grammar.hpp:18:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/qi/nonterminal/rule.hpp:16:
In file included from /home/wlynch/Boost/1.47.0/include/boost/function.hpp:64:
In file included from /home/wlynch/Boost/1.47.0/include/boost/preprocessor/iteration/detail/iter/forward1.hpp:67:
In file included from /home/wlynch/Boost/1.47.0/include/boost/function/detail/function_iterate.hpp:14:
In file included from /home/wlynch/Boost/1.47.0/include/boost/function/detail/maybe_include.hpp:33:
/home/wlynch/Boost/1.47.0/include/boost/function/function_template.hpp:1042:5: note: in instantiation of function template specialization 'boost::function4<bool,
boost::spirit::lex::lexertl::iterator<boost::spirit::lex::lexertl::functor<boost::spirit::lex::lexertl::token<char const *, boost::mpl::vector0<mpl_::na>, mpl_::bool_<1>, unsigned long>,
lexertl::detail::data, char const *, mpl_::bool_<1>, mpl_::bool_<1> > > &, boost::spirit::lex::lexertl::iterator<boost::spirit::lex::lexertl::functor<boost::spirit::lex::lexertl::token<char const *,
boost::mpl::vector0<mpl_::na>, mpl_::bool_<1>, unsigned long>, lexertl::detail::data, char const *, mpl_::bool_<1>, mpl_::bool_<1> > > const &, boost::spirit::context<boost::fusion::cons<ident &,
boost::fusion::nil>, boost::fusion::vector0<void> > &, boost::spirit::unused_type const
&>::function4<boost::spirit::qi::detail::parser_binder<boost::spirit::lex::reference<boost::spirit::lex::token_def<std::basic_string<char>, char, unsigned long> const, unsigned long>, mpl_::bool_<1> > >'
requested here
base_type(f)
^
/home/wlynch/Boost/1.47.0/include/boost/function/function_template.hpp:1083:5: note: in instantiation of function template specialization 'boost::function<bool
(boost::spirit::lex::lexertl::iterator<boost::spirit::lex::lexertl::functor<boost::spirit::lex::lexertl::token<char const *, boost::mpl::vector0<mpl_::na>, mpl_::bool_<1>, unsigned long>,
lexertl::detail::data, char const *, mpl_::bool_<1>, mpl_::bool_<1> > > &, boost::spirit::lex::lexertl::iterator<boost::spirit::lex::lexertl::functor<boost::spirit::lex::lexertl::token<char const *,
boost::mpl::vector0<mpl_::na>, mpl_::bool_<1>, unsigned long>, lexertl::detail::data, char const *, mpl_::bool_<1>, mpl_::bool_<1> > > const &, boost::spirit::context<boost::fusion::cons<ident &,
boost::fusion::nil>, boost::fusion::vector0<void> > &, boost::spirit::unused_type const
&)>::function<boost::spirit::qi::detail::parser_binder<boost::spirit::lex::reference<boost::spirit::lex::token_def<std::basic_string<char>, char, unsigned long> const, unsigned long>, mpl_::bool_<1> > >'
requested here
self_type(f).swap(*this);
^
In file included from ../reduced-example/reduced.cpp:3:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex.hpp:15:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex/tokenize_and_parse.hpp:15:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/qi/nonterminal/grammar.hpp:18:
/home/wlynch/Boost/1.47.0/include/boost/spirit/home/qi/nonterminal/rule.hpp:182:19: note: in instantiation of function template specialization 'boost::function<bool
(boost::spirit::lex::lexertl::iterator<boost::spirit::lex::lexertl::functor<boost::spirit::lex::lexertl::token<char const *, boost::mpl::vector0<mpl_::na>, mpl_::bool_<1>, unsigned long>,
lexertl::detail::data, char const *, mpl_::bool_<1>, mpl_::bool_<1> > > &, boost::spirit::lex::lexertl::iterator<boost::spirit::lex::lexertl::functor<boost::spirit::lex::lexertl::token<char const *,
boost::mpl::vector0<mpl_::na>, mpl_::bool_<1>, unsigned long>, lexertl::detail::data, char const *, mpl_::bool_<1>, mpl_::bool_<1> > > const &, boost::spirit::context<boost::fusion::cons<ident &,
boost::fusion::nil>, boost::fusion::vector0<void> > &, boost::spirit::unused_type const
&)>::operator=<boost::spirit::qi::detail::parser_binder<boost::spirit::lex::reference<boost::spirit::lex::token_def<std::basic_string<char>, char, unsigned long> const, unsigned long>, mpl_::bool_<1> > >'
requested here
lhs.f = detail::bind_parser<Auto>(
^
/home/wlynch/Boost/1.47.0/include/boost/spirit/home/qi/nonterminal/rule.hpp:230:13: note: in instantiation of function template specialization
'boost::spirit::qi::rule<boost::spirit::lex::lexertl::iterator<boost::spirit::lex::lexertl::functor<boost::spirit::lex::lexertl::token<char const *, boost::mpl::vector0<mpl_::na>, mpl_::bool_<1>, unsigned
long>, lexertl::detail::data, char const *, mpl_::bool_<1>, mpl_::bool_<1> > >, ident (), boost::spirit::unused_type, boost::spirit::unused_type, boost::spirit::unused_type>::define<mpl_::bool_<1>,
boost::spirit::lex::token_def<std::basic_string<char>, char, unsigned long> >' requested here
define<mpl::true_>(r, expr, traits::matches<qi::domain, Expr>());
^
../reduced-example/reduced.cpp:23:9: note: in instantiation of function template specialization 'boost::spirit::qi::operator%=<boost::spirit::lex::token_def<std::basic_string<char>, char, unsigned long> >'
requested here
start %= lexer.identifier;
^
../reduced-example/reduced.cpp:9:8: note: candidate constructor (the implicit default constructor) not viable: requires 0 arguments, but 2 were provided
struct ident {
^
../reduced-example/reduced.cpp:9:8: note: candidate constructor (the implicit copy constructor) not viable: requires 1 argument, but 2 were provided
In file included from ../reduced-example/reduced.cpp:3:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex.hpp:13:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex/lexer.hpp:14:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex/lexer/token_def.hpp:17:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/qi/parser.hpp:15:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/qi/domain.hpp:18:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/support/context.hpp:18:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/support/nonterminal/expand_arg.hpp:20:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/support/string_traits.hpp:16:
/home/wlynch/Boost/1.47.0/include/boost/spirit/home/support/container.hpp:368:22: error: no member named 'empty' in 'ident'
return c.empty();
~ ^
/home/wlynch/Boost/1.47.0/include/boost/spirit/home/support/container.hpp:375:47: note: in instantiation of member function 'boost::spirit::traits::is_empty_container<ident, void>::call' requested here
return is_empty_container<Container>::call(c);
^
In file included from ../reduced-example/reduced.cpp:3:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex.hpp:13:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex/lexer.hpp:14:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex/lexer/token_def.hpp:20:
/home/wlynch/Boost/1.47.0/include/boost/spirit/home/qi/detail/assign_to.hpp:37:17: note: in instantiation of function template specialization 'boost::spirit::traits::is_empty<ident>' requested here
if (traits::is_empty(attr))
^
/home/wlynch/Boost/1.47.0/include/boost/spirit/home/qi/detail/assign_to.hpp:94:13: note: in instantiation of member function 'boost::spirit::traits::assign_to_attribute_from_iterators<ident, char const *,
void>::call' requested here
call(first, last, attr);
^
In file included from ../reduced-example/reduced.cpp:4:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex/lexer/lexertl/lexer.hpp:20:
/home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex/lexer/lexertl/token.hpp:530:13: note: in instantiation of function template specialization 'boost::spirit::traits::assign_to<char const *, ident>'
requested here
spirit::traits::assign_to(t.value().begin(), t.value().end(), attr);
^
In file included from ../reduced-example/reduced.cpp:3:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex.hpp:13:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex/lexer.hpp:14:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex/lexer/token_def.hpp:20:
/home/wlynch/Boost/1.47.0/include/boost/spirit/home/qi/detail/assign_to.hpp:330:59: note: in instantiation of member function 'boost::spirit::traits::assign_to_attribute_from_value<ident,
boost::spirit::lex::lexertl::token<char const *, boost::mpl::vector0<mpl_::na>, mpl_::bool_<1>, unsigned long>, void>::call' requested here
assign_to_attribute_from_value<Attribute, T>::call(val, attr);
^
/home/wlynch/Boost/1.47.0/include/boost/spirit/home/qi/detail/assign_to.hpp:353:9: note: (skipping 7 contexts in backtrace; use -ftemplate-backtrace-limit=0 to see all)
detail::assign_to(val, attr, is_not_wrapped_container());
^
In file included from ../reduced-example/reduced.cpp:3:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex.hpp:15:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex/tokenize_and_parse.hpp:15:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/qi/nonterminal/grammar.hpp:18:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/qi/nonterminal/rule.hpp:16:
In file included from /home/wlynch/Boost/1.47.0/include/boost/function.hpp:64:
In file included from /home/wlynch/Boost/1.47.0/include/boost/preprocessor/iteration/detail/iter/forward1.hpp:67:
In file included from /home/wlynch/Boost/1.47.0/include/boost/function/detail/function_iterate.hpp:14:
In file included from /home/wlynch/Boost/1.47.0/include/boost/function/detail/maybe_include.hpp:33:
/home/wlynch/Boost/1.47.0/include/boost/function/function_template.hpp:1042:5: note: in instantiation of function template specialization 'boost::function4<bool,
boost::spirit::lex::lexertl::iterator<boost::spirit::lex::lexertl::functor<boost::spirit::lex::lexertl::token<char const *, boost::mpl::vector0<mpl_::na>, mpl_::bool_<1>, unsigned long>,
lexertl::detail::data, char const *, mpl_::bool_<1>, mpl_::bool_<1> > > &, boost::spirit::lex::lexertl::iterator<boost::spirit::lex::lexertl::functor<boost::spirit::lex::lexertl::token<char const *,
boost::mpl::vector0<mpl_::na>, mpl_::bool_<1>, unsigned long>, lexertl::detail::data, char const *, mpl_::bool_<1>, mpl_::bool_<1> > > const &, boost::spirit::context<boost::fusion::cons<ident &,
boost::fusion::nil>, boost::fusion::vector0<void> > &, boost::spirit::unused_type const
&>::function4<boost::spirit::qi::detail::parser_binder<boost::spirit::lex::reference<boost::spirit::lex::token_def<std::basic_string<char>, char, unsigned long> const, unsigned long>, mpl_::bool_<1> > >'
requested here
base_type(f)
^
/home/wlynch/Boost/1.47.0/include/boost/function/function_template.hpp:1083:5: note: in instantiation of function template specialization 'boost::function<bool
(boost::spirit::lex::lexertl::iterator<boost::spirit::lex::lexertl::functor<boost::spirit::lex::lexertl::token<char const *, boost::mpl::vector0<mpl_::na>, mpl_::bool_<1>, unsigned long>,
lexertl::detail::data, char const *, mpl_::bool_<1>, mpl_::bool_<1> > > &, boost::spirit::lex::lexertl::iterator<boost::spirit::lex::lexertl::functor<boost::spirit::lex::lexertl::token<char const *,
boost::mpl::vector0<mpl_::na>, mpl_::bool_<1>, unsigned long>, lexertl::detail::data, char const *, mpl_::bool_<1>, mpl_::bool_<1> > > const &, boost::spirit::context<boost::fusion::cons<ident &,
boost::fusion::nil>, boost::fusion::vector0<void> > &, boost::spirit::unused_type const
&)>::function<boost::spirit::qi::detail::parser_binder<boost::spirit::lex::reference<boost::spirit::lex::token_def<std::basic_string<char>, char, unsigned long> const, unsigned long>, mpl_::bool_<1> > >'
requested here
self_type(f).swap(*this);
^
In file included from ../reduced-example/reduced.cpp:3:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex.hpp:15:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/lex/tokenize_and_parse.hpp:15:
In file included from /home/wlynch/Boost/1.47.0/include/boost/spirit/home/qi/nonterminal/grammar.hpp:18:
/home/wlynch/Boost/1.47.0/include/boost/spirit/home/qi/nonterminal/rule.hpp:182:19: note: in instantiation of function template specialization 'boost::function<bool
(boost::spirit::lex::lexertl::iterator<boost::spirit::lex::lexertl::functor<boost::spirit::lex::lexertl::token<char const *, boost::mpl::vector0<mpl_::na>, mpl_::bool_<1>, unsigned long>,
lexertl::detail::data, char const *, mpl_::bool_<1>, mpl_::bool_<1> > > &, boost::spirit::lex::lexertl::iterator<boost::spirit::lex::lexertl::functor<boost::spirit::lex::lexertl::token<char const *,
boost::mpl::vector0<mpl_::na>, mpl_::bool_<1>, unsigned long>, lexertl::detail::data, char const *, mpl_::bool_<1>, mpl_::bool_<1> > > const &, boost::spirit::context<boost::fusion::cons<ident &,
boost::fusion::nil>, boost::fusion::vector0<void> > &, boost::spirit::unused_type const
&)>::operator=<boost::spirit::qi::detail::parser_binder<boost::spirit::lex::reference<boost::spirit::lex::token_def<std::basic_string<char>, char, unsigned long> const, unsigned long>, mpl_::bool_<1> > >'
requested here
lhs.f = detail::bind_parser<Auto>(
^
/home/wlynch/Boost/1.47.0/include/boost/spirit/home/qi/nonterminal/rule.hpp:230:13: note: in instantiation of function template specialization
'boost::spirit::qi::rule<boost::spirit::lex::lexertl::iterator<boost::spirit::lex::lexertl::functor<boost::spirit::lex::lexertl::token<char const *, boost::mpl::vector0<mpl_::na>, mpl_::bool_<1>, unsigned
long>, lexertl::detail::data, char const *, mpl_::bool_<1>, mpl_::bool_<1> > >, ident (), boost::spirit::unused_type, boost::spirit::unused_type, boost::spirit::unused_type>::define<mpl_::bool_<1>,
boost::spirit::lex::token_def<std::basic_string<char>, char, unsigned long> >' requested here
define<mpl::true_>(r, expr, traits::matches<qi::domain, Expr>());
^
../reduced-example/reduced.cpp:23:9: note: in instantiation of function template specialization 'boost::spirit::qi::operator%=<boost::spirit::lex::token_def<std::basic_string<char>, char, unsigned long> >'
requested here
start %= lexer.identifier;
^
答案 0 :(得分：3)
我最终意识到我定义的结构在精神上被用作元组。因为精神会尽量减少群体（例如，optional<int, int>是optional<int>）。因此，我猜测tuple<A>将转换为A。似乎就是这种情况。
我能够将破坏代码的测试用例进一步减少到以下内容：
#include <boost/fusion/include/adapt_struct.hpp>
#include <boost/spirit/home/qi.hpp>
#include <string>
struct ident {
std::string a;
};
BOOST_FUSION_ADAPT_STRUCT(ident,
(std::string, a)
)
int main() {
boost::spirit::qi::rule<const char*, ident()> r;
r = boost::spirit::lexeme["abc"];
}
通过我发现的以下邮件列表发布（1，2），我可以通过以下方式解决此问题：
r = boost::spirit::lexeme["abc"] >> boost::spirit::eps;
虽然不是很优雅，但它至少解决了这个问题。如果其他人有一个方法来执行单个元素结构，我会非常感兴趣。