當我將輸入解析爲std :: string時,我得到了字符串,但是當我將它解析爲double_時,融合結構包含一些非常小的數字,而不是預期的數字。爲什麼我不能解析這個double_?
#include <boost/spirit/include/qi.hpp>
#include <boost/fusion/include/adapt_struct.hpp>
#include <string>
// http://www.boost.org/doc/libs/1_57_0/libs/spirit/example/qi/employee.cpp
namespace FormatConverter {
namespace qi = boost::spirit::qi;
namespace ascii = boost::spirit::ascii;
// TODO: should this have an initializer?
struct asc {
double timestamp;
};
}
BOOST_FUSION_ADAPT_STRUCT(
FormatConverter::asc,
(double, timestamp)
)
namespace FormatConverter {
template <typename Iterator>
struct asc_parser : qi::grammar< Iterator, asc(), ascii::space_type >
{
asc_parser()
: asc_parser::base_type(start) {
timestamp %= qi::double_ ;
start %= timestamp ;
;
}
qi::rule< Iterator, double, ascii::space_type > timestamp;
qi::rule< Iterator, asc(), ascii::space_type > start;
};
}
而且我有測試此:
#define BOOST_TEST_MODULE parser
#include <boost/test/included/unit_test.hpp>
#include "../FormatConverter/FormatConverter.h"
#include <string>
BOOST_AUTO_TEST_SUITE(TestSuite1)
BOOST_AUTO_TEST_CASE(timestamp) {
namespace qi = boost::spirit::qi;
namespace ascii = boost::spirit::ascii;
using iterator_type = std::string::iterator;
using parser_type = FormatConverter::asc_parser<iterator_type>;
parser_type grammar;
FormatConverter::asc record;
std::string str("161.096841 ");
auto beg = str.begin();
auto end = str.end();
auto success = qi::phrase_parse(beg, end, grammar, ascii::space, record);
BOOST_REQUIRE(success);
BOOST_REQUIRE(beg==end);
std::cout << "timestamp: " << boost::fusion::as_vector(record) << std::endl;
}
BOOST_AUTO_TEST_SUITE_END()
每次,我發誓我不能正確書寫它。我知道這一點,但這一直是我輸入它的方式 – user2240431 2014-11-06 23:33:56