as_returns

turn an iterable argument into a multiple-return type

template <typename T>
struct as_returns_t { ... };

template <typename T>
as_returns_t<T> as_returns( T&& );

This allows you to wrap up a source that has begin and end iterator-returning functions on it and return it as multiple results into Lua. To have more control over the returns, use sol::variadic_results.

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#define SOL_ALL_SAFETIES_ON 1
#include <sol/sol.hpp>

#include "assert.hpp"

#include <string>
#include <set>

int main () {
	sol::state lua;

	lua.set_function("f", []() {
		std::set<std::string> results{ "arf", "bark", "woof" };
		return sol::as_returns(std::move(results));
	});
	
	lua.script("v1, v2, v3 = f()");

	std::string v1 = lua["v1"];
	std::string v2 = lua["v2"];
	std::string v3 = lua["v3"];

	c_assert(v1 == "arf");
	c_assert(v2 == "bark");
	c_assert(v3 == "woof");

	return 0;		
}