Simple object with metatable

local function object()
    local obj = {}
    local variable1 = 5
    local variable2 = "Hello John!"

    local mt = {
        -- get a value from this object
        __index = function(obj, name)
            if name=="variable1" then
                return variable1
            elseif name=="variable2" then
                return variable2
            end
        end,

        __newindex = function(obj, name, value)
            if name=="variable1" then
                variable1 = value
            elseif name=="variable2" then
                variable2 = value
            end
        end,
    }

    setmetatable(obj, mt)
    return obj
end

local o1 = object()
print(o1.variable1, o1.variable2)
o1.variable1 = 100
o1.variable2 = "Hi!"
print(o1.variable1, o1.variable2)