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#define SOL_ALL_SAFETIES_ON 1
#include <sol/sol.hpp>
#include <iostream>
struct ship {
int bullets = 20;
int life = 100;
bool shoot() {
if (bullets > 0) {
--bullets;
// successfully shot
return true;
}
// cannot shoot
return false;
}
bool hurt(int by) {
life -= by;
// have we died?
return life < 1;
}
};
int main() {
std::cout << "=== usertype basics ===" << std::endl;
static const bool way_1 = true;
sol::state lua;
lua.open_libraries(sol::lib::base);
if (way_1) {
lua.new_usertype<ship>(
"ship", // the name of the class, as you want it
// to be used in lua List the member
// functions you wish to bind:
// "name_of_item",
// &class_name::function_or_variable
"shoot",
&ship::shoot,
"hurt",
&ship::hurt,
// bind variable types, too
"life",
&ship::life,
// names in lua don't have to be the same as C++,
// but it probably helps if they're kept the same,
// here we change it just to show its possible
"bullet_count",
&ship::bullets);
}
else {
// set usertype explicitly, with the given name
sol::usertype<ship> usertype_table
= lua.new_usertype<ship>("ship");
usertype_table["shoot"] = &ship::shoot;
usertype_table["hurt"] = &ship::hurt;
usertype_table["life"] = &ship::life;
usertype_table["bullet_count"] = &ship::bullets;
}
const auto& code = R"(
fwoosh = ship.new()
-- note the ":" that is there: this is mandatory for member function calls
-- ":" means "pass self" in Lua
local success = fwoosh:shoot()
local is_dead = fwoosh:hurt(20)
-- check if it works
print(is_dead) -- the ship is not dead at this point
print(fwoosh.life .. "life left") -- 80 life left
print(fwoosh.bullet_count) -- 19
)";
lua.script(code);
std::cout << std::endl;
return 0;
}
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