parsing interleaved lines with boost spirit - c++

Question

I am new to spirit and currently trying to parse an ini like file into a struct. Creating the grammar is ok, but the mapping generation is still some kind of magic to me. The file looks like this:
[fine]
#cmp1
#cmp2
muh=b
[fail]
#cmp1
a=b
#cmp2
it works as long as i have the requirements and properties ordered (section "fine") but I can't get it to work if the requirements and properties are interleaved (section "fail"). My struct definition looks like this:
typedef std::map<std::string, std::string> Pairs;
struct Section
{
std::string name;
std::vector<std::string> requirements;
Pairs properties;
};
BOOST_FUSION_ADAPT_STRUCT(
Section,
(std::string, name)
(std::vector<std::string>, requirements)
(Pairs, properties)
)
My current grammar looks like this:
template <typename Iterator, typename Skipper>
struct SectionParser : qi::grammar<Iterator, Section(), Skipper>
{
qi::rule<Iterator, Section(), Skipper> section;
qi::rule<Iterator, std::pair<std::string, std::string>(), Skipper> pair;
qi::rule<Iterator, std::vector<std::string>()> requirements;
qi::rule<Iterator, std::string()> key, value, sectionIdent, name, component;
SectionParser()
: SectionParser::base_type(section, "entity grammar")
{
using namespace qi;
sectionIdent = *(qi::char_ - (qi::lit('[') | qi::lit(']') | qi::eol));
name = *qi::eol > qi::lit('[') > sectionIdent > qi::lit(']') > (qi::eol | qi::eoi);
component = qi::char_('#') > *(qi::char_ - (qi::eol)) > (qi::eol | qi::eoi);
value = *(qi::char_ - (qi::eol | qi::eoi));
key = qi::char_("a-zA-Z_") > *qi::char_("a-zA-Z_0-9");
pair = key > qi::lit('=') > value > (qi::eol | qi::eoi);
section = name >> *component >> *pair;
}
};
Thats how I run the parser:
std::vector<Section> sections;
bool ok = phrase_parse(first, last, (sectionParser % +qi::eol) >> *qi::eol > qi::eoi, qi::blank, sections);
I also have the feeling that i made the line ending handling more complicated than it should be...

Answer 1

After reading parsing into several vector members i found a solution using only semantic actions.
The struct definition stays the same:
struct Section
{
std::string name;
std::vector<std::string> requirements;
Pairs properties;
};
dont use adapt struct anymore.
The grammar changes to:
template <typename Iterator, typename Skipper>
struct SectionParser : qi::grammar<Iterator, Section(), Skipper>
{
qi::rule<Iterator, Section(), Skipper> start;
qi::rule<Iterator, std::string()> value, ident, name, component;
qi::rule<Iterator, std::pair<std::string, std::string>()> pair;
SectionParser()
: SectionParser::base_type(start, "section grammar")
{
auto add_component = phx::push_back(phx::bind(&Section::requirements, qi::_val), qi::_1);
auto add_pair = phx::insert(phx::bind(&Section::properties, qi::_val), qi::_1);
auto set_name = phx::assign(phx::bind(&Section::name, qi::_val), qi::_1);
ident = +qi::char_("a-zA-Z0-9_");
component = qi::char_('#') > ident >> (qi::eol | qi::eoi);
value = *(qi::char_ - (qi::eol | qi::eoi));
pair = ident > qi::lit('=') > value >> (qi::eol | qi::eoi);
name = qi::lit('[') > ident > qi::lit(']') >> (qi::eol | qi::eoi);
start = name[set_name] >> *(component[add_component] | pair[add_pair]);
}
};