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#define SOL_ALL_SAFETIES_ON 1
#define SOL_ENABLE_INTEROP 1 // MUST be defined to use interop features
#include <sol/sol.hpp>
#include "Player.h"
#include <tolua++.h>
// pick or replace the include
// with whatever generated file you've created
#include "tolua_Player.h"
#include <iostream>
#include <assert.hpp>
// tolua code lifted from some blog, if the link dies
// I don't know where else you're gonna find the reference,
// http://usefulgamedev.weebly.com/tolua-example.html
/* NOTE: there is no sol_lua_interop_get here,
because tolua types are -- thankfully -- memory-compatible
in most cases with sol.
Please check other examples like kaguya or LuaBribe for an example
of how to also write the getter for your type*/
template <typename T, typename Handler>
inline bool sol_lua_interop_check(sol::types<T>, lua_State* L, int relindex, sol::type index_type, Handler&& handler, sol::stack::record& tracking) {
tracking.use(1);
// just marking unused parameters for no compiler warnings
(void)index_type;
(void)handler;
int index = lua_absindex(L, relindex);
std::string name = sol::detail::short_demangle<T>();
tolua_Error tolua_err{};
int r = tolua_isusertype(L, index, name.c_str(), 0, &tolua_err);
if (r == 0) {
// tolua seems to leave garbage on the stack
// when the check fails
// thanks, tolua
lua_pop(L, 2);
return false;
}
return true;
}
void register_sol_stuff(lua_State* L) {
// grab raw state and put into state_view
// state_view is cheap to construct
sol::state_view lua(L);
// bind and set up your things: everything is entirely self-contained
lua["f"] = sol::overload(
[](Player& from_tolua) {
std::cout << "calling 1-argument version with tolua-created Player { health:" << from_tolua.getHealth() << " }" << std::endl;
c_assert(from_tolua.getHealth() == 4);
},
[](Player& from_tolua, int second_arg) {
std::cout << "calling 2-argument version with tolua-created Player { health: " << from_tolua.getHealth() << " } and integer argument of " << second_arg << std::endl;
c_assert(from_tolua.getHealth() == 4);
c_assert(second_arg == 5);
});
}
void check_with_sol(lua_State* L) {
sol::state_view lua(L);
Player& obj = lua["obj"];
(void)obj;
c_assert(obj.getHealth() == 4);
}
int main(int, char* []) {
std::cout << "=== interop example (tolua) ===" << std::endl;
std::cout << "(code lifted from a sol2 user's use case: https://github.com/ThePhD/sol2/issues/511#issuecomment-331729884)" << std::endl;
lua_State* L = luaL_newstate();
luaL_openlibs(L); // initalize all lua standard library functions
tolua_open(L); // initalize tolua
tolua_Player_open(L); // make Player class accessible from LUA
register_sol_stuff(L);
const auto code = R"(
obj = Player:new()
obj:setHealth(4)
f(obj) -- call 1 argument version
f(obj, 5) -- call 2 argument version
)";
if (luaL_dostring(L, code)) {
lua_error(L); // crash on error
}
check_with_sol(L);
return 0;
}
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