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#define SOL_ALL_SAFETIES_ON 1
#include <sol/sol.hpp>
#include <tuple>
#include "assert.hpp"
#include <iostream>
int main() {
std::cout << "=== multi results ===" << std::endl;
sol::state lua;
lua.open_libraries(sol::lib::base);
// multi-return functions are supported using
// std::tuple as the transfer type,
// sol::as_returns for containers,
// and sol::variadic_results for more special things
lua.set_function("multi_tuple", [] {
return std::make_tuple(10, "goodbye");
});
lua.script("print('calling multi_tuple')");
lua.script("print(multi_tuple())");
lua.script("x, y = multi_tuple()");
lua.script("assert(x == 10 and y == 'goodbye')");
auto multi = lua.get<sol::function>("multi_tuple");
int first;
std::string second;
// tie the values
sol::tie(first, second) = multi();
// use the values
c_assert(first == 10);
c_assert(second == "goodbye");
// sol::as_returns
// works with any iterable,
// but we show off std::vector here
lua.set_function("multi_containers", [] (bool add_extra) {
std::vector<int> values{55, 66};
if (add_extra) {
values.push_back(77);
}
return sol::as_returns(std::move(values));
});
lua.script("print('calling multi_containers')");
lua.script("print(multi_containers(false))");
lua.script("a, b, c = multi_containers(true)");
int a = lua["a"];
int b = lua["b"];
int c = lua["c"];
c_assert(a == 55);
c_assert(b == 66);
c_assert(c == 77);
// sol::variadic_results
// you can push objects of different types
// note that sol::this_state is a transparent
// argument: you don't need to pass
// that state through Lua
lua.set_function("multi_vars", [](int a, bool b, sol::this_state L) {
sol::variadic_results values;
values.push_back({ L, sol::in_place_type<int>, a });
values.push_back({ L, sol::in_place_type<bool>, b });
values.push_back({ L, sol::in_place, "awoo" });
return values;
});
lua.script("print('calling multi_vars')");
lua.script("print(multi_vars(2, false))");
lua.script("t, u, v = multi_vars(42, true)");
int t = lua["t"];
bool u = lua["u"];
std::string v = lua["v"];
c_assert(t == 42);
c_assert(u);
c_assert(v == "awoo");
return 0;
}
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