Using Lua with C++ iterating over table examle

#include <iostream>
#include <string>
#include <unordered_map>

extern "C" {
#include "lua.h"
#include "lauxlib.h"
#include "lualib.h"
}
#include <LuaBridge.h>

std::unordered_map<std::string, luabridge::LuaRef> getKeyValueMap(const luabridge::LuaRef& table)
{
    using namespace luabridge;
    std::unordered_map<std::string, LuaRef> result;
    if (table.isNil()) { return result; }

    auto L = table.state();
    push(L, table); // push table

    lua_pushnil(L);  // push nil, so lua_next removes it from stack and puts (k, v) on stack
    while (lua_next(L, -2) != 0) { // -2, because we have table at -1
        if (lua_isstring(L, -2)) { // only store stuff with string keys
            result.emplace(lua_tostring(L, -2), LuaRef::fromStack(L, -1));
        }
        lua_pop(L, 1); // remove value, keep key for lua_next
    }

    lua_pop(L, 1); // pop table
    return result;
}

int main()
{
    lua_State* L = luaL_newstate();
    luaL_openlibs(L);

    luabridge::LuaRef table = luabridge::newTable(L);
    table["someKey"] = 8;
    table["someAnotherKey"] = "this is a string";

    // print the stuff
    std::cout << "Here's what table contains:" << std::endl;
    for (auto& pair : getKeyValueMap(table)) {
        auto& key = pair.first;
        auto& value = pair.second;

        std::cout << key << " = ";
        if (value.isNumber()) {
            std::cout << value.cast<int>();
        } else if (value.isString()) {
            std::cout << value.cast<std::string>();
        }
        std::cout << std::endl;
    }
}