Header-only C++20 simple sol2 wrapper

Description

• Lua is a singleton.

Example

Case 1

void hello()
{
	std::cout << "Hello!";
}

int main()
{
	LUA_GET(); // auto& lua = Lua::get();

	Lua::Table obj = lua.createObject("test");
	obj.setMethod("hi", hello);

	lua.exec("test:hi()");

	Lua::Object result = lua.execFile("Data/MyScript.lua")
	int num = result.as<int>();

	lua.shutdown();

	return 0;
}

Case 2

class Weapon
{
public:
	static void bindLua()
	{
		LUA_GET();

		auto wpn = lua.bindClass<Weapon>("Weapon");
		wpn.set("damage",    &Weapon::m_damage);
		wpn.set("getName",   &Weapon::getName);  // name is read-only
	}

	Weapon(const std::string& name, int damage) :
		m_name   (name),
		m_damage (damage) { }

	const std::string& getName   () const { return m_name; }
	int                getDamage () const { return m_damage; }

private:
	std::string m_name;
	int         m_damage;
};

struct Human
{
	using WeaponPtr = std::unique_ptr<Weapon>;

	std::vector<WeaponPtr> sharedWeapons;

	void registerLua()
	{
		LUA_GET();

		Lua::Table player = lua.createStaticObject("Player");

		player.setField("weapon", Weapon("Pistol", 10));

		player.setMethod("getSharedWeapons", [this, &lua] // -> vector<Lua::Object>
			{
				std::vector<Lua::Object> luaWpns;

				for (auto& wpn : sharedWeapons)
				{
					luaWpns.emplace_back(
						lua.toLuaObject(*wpn)
					);
				}

				return luaWpns;
			}
		);
	}
};

Lua::Object findWeapon(const string& name, Lua::Object container)
{
	LUA_GET();

	std::vector<Weapon> weapons = container;

	for (const auto& wpn : weapons)
	{
		if (wpn.getName() == name)
			return lua.toLuaObject(wpn);
	}

	return lua.toLuaObject(lua.nil);
}

int main()
{
	Weapon::bindLua();

	Human human;
	human.registerLua();

	auto utility = lua.createStaticObject("util");
	utility.setMethod("findWeapon", findWeapon);

	lua.exec(R"(
		local weapons = Player:getSharedWeapons()

		local wpn1  = weapons[0]
		wpn1.damage = 100

		local wpn2 = util:findWeapon('Rifle', weapons)
	)");

	lua.shutdown();

	return 0;
}

License

This project is under MIT License.

Copyright (c) 2024 3lyrion

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.