Re: fusion pair issue?

Thank you so much for your answer!

I was struck by this version:

> See http://coliru.stacked-crooked.com/a/2a847ad1037640f3

No need to know the member names of a pair for a BOOST_FUSION wrapping.

Given ciere.com/cppnow15/x3_docs/spirit/tutorials/rexpr.html:

  "We need to tell fusion about our rexpr struct to make it a
  first-class fusion citizen"

I would never have guessed your solution was possible.

Fusion is still necessary via

  #include <boost/fusion/include/std_pair.hpp>

but nicely hidden. I have no idea what the correct fusion wrapping would
be for a map (we had to know and list "first" and "second" for the pair),
however thankfully I don't need to know!

Thanks again,

Patrick

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#define BOOST_SPIRIT_X3_DEBUG

#include <map>

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

namespace x3 = boost::spirit::x3;

struct result
{
	std::map<std::string, std::string> both;
};

int main()
{
	std::string buf("one two;three four;");
	std::string::const_iterator iter = buf.begin();
	std::string::const_iterator end = buf.end();
	result res;
	bool ok = x3::parse(iter, end,
		+( +x3::alnum >> ' ' >> +x3::alnum >> ';' ),
		res.both);
	if (!ok)
		std::cout << "Parsing failed\n";
	else if (iter != end)
		std::cout << "Bit left over at the end: "
		          << std::string(iter, end) << std::endl;
	else
		for (auto p : res.both) {
			std::cout << "found: " << p.first << ' '
			          << p.second << std::endl;
		}

	return 0;
}