[Follow Up] How would be I able to use self variables from a base class to a subclass?

[ChronicallyOnlin_e (Fandomized)]

Heya Everyone!!

This is a simple follow up from a previous post I’ve made here. I didn’t want to drag it from there so I’ll do a follow up.
For anyone wondering from the previous post, I was trying to access self.Robotxian from the base class, that being ROBOTXIAN_MAIN. Luckily, I was able to get an answer telling me that I wasn’t actually returning self and thus being unable to use it. The fix was simply just adding self to the table inside of the constructor I am using.

The issue now is that I’m trying to use classesSelf (Check the post to what I’m talking about) to use functions inside of the subclass (Which is BUILDER_CLASS) alongside trying to use classesSelf inside of said functions (Such as a Build function.)

Keep in mind that I’m still new to OOP alongside making this post in 11 PM, so I’m pretty sleepy.

ROBOTXIAN_MAIN (Just in case anyone needs it)

--[[INFO]]--
--//ROBOTXIAN_MAIN is the base class of both the 'Builder' and 'Fighter' class.
--//This contains essential functions for both class to work such as pathfinding or even creating Robotxians in the first place.

--[[SERVICES]]--
local ServerStorage = game:GetService("ServerStorage")
local ReplicatedStorage = game:GetService("ReplicatedStorage")
local Debris = game:GetService("Debris")

--[[FOLDERS]]--
local Events_Folder = ReplicatedStorage:WaitForChild("EVENTS")
local Preset_Player_Models_Folder = ServerStorage:WaitForChild("PRESET_PLAYER_MODELS")

--[[MODULE]]--
local ROBOTXIAN_MAIN_FUNCTION = {}
ROBOTXIAN_MAIN_FUNCTION.__index = ROBOTXIAN_MAIN_FUNCTION

--//Spawning and despawning the robotxian.
function ROBOTXIAN_MAIN_FUNCTION.CreateNewRobotxian()
	local self = {}
	
	--//Just to be safe, I'd assume  this is where I'd spawn them in.
	self.Robotxian = ServerStorage.PRESET_PLAYER_MODELS.R6:Clone()
	self.Robotxian.Parent = game.Workspace
	
	return setmetatable({self = self}, ROBOTXIAN_MAIN_FUNCTION)
end


--//Pathfinding
function ROBOTXIAN_MAIN_FUNCTION:Pathfind()
	--//TBA
end

return ROBOTXIAN_MAIN_FUNCTION

BUILDER_CLASS

--[[INFO]]--
--//The 'Builder' class is one of the two classes a robotxian can have.
--//As the name says, robotxians with the class will be able to spawn in parts and modify them to their liking.
--//Additionally, robotxians will also be able to apply both decals and a handful of special effects such as Fire or Sparkles.
--//Generally, robotxians with the class will just spawn in random parts but will occasionally start building actual stuff such as a small house or a poorly made robloxian.

--[[BASE CLASS]]--
local ROBOTXIAN_MAIN = require(script.Parent.Parent.ROBOTXIAN_MAIN)

--[[MODULE]]--
local BUILDER_CLASS_MODULE = setmetatable({}, {__index = ROBOTXIAN_MAIN})
BUILDER_CLASS_MODULE.__index = BUILDER_CLASS_MODULE

function BUILDER_CLASS_MODULE.CreateNewBuilderRobotxian()
	local Robotxian = ROBOTXIAN_MAIN.CreateNewRobotxian()
	local RobotxianSelf = Robotxian.self
end

function BUILDER_CLASS_MODULE:Build()
	--//Trying to use self here.
end

return BUILDER_CLASS_MODULE

[WizulousThe2nd]

Simple, just use self.
Here you are basically inheriting the Robotxian class.

What you do is, just assign this to self.

local BUILDER_CLASS_MODULE = setmetatable({}, {__index = ROBOTXIAN_MAIN})
BUILDER_CLASS_MODULE.__index = BUILDER_CLASS_MODULE

function BUILDER_CLASS_MODULE.CreateNewBuilderRobotxian()
    -- Now you inherit it
    local self = ROBOTXIAN_MAIN.CreateNewRobotxian()
    self.builder = "cool"

    print(self)
    -- Shows all of robotxian class + self.builder = "cool" + self:Build() 

    return setmetatable(self, BUILDER_CLASS_MODULE)
end

Also, self is just a table.
No need to do {self = self}, just self, ROBOTXIAN_MAIN_FUNCTION

return setmetatable({self = self}, ROBOTXIAN_MAIN_FUNCTION)

Also this, which is called “Class-Level inheritance”
basically here you’re inheriting from the base class itself, not from instances created by it…
→ local ROBOTXIAN_MAIN_FUNCTION = {}
Yes, it’s basically requiring the module, but you’re putting it INSIDE BUILDER_CLASS_MODULE, so if you do local Robotxian = BUILDER_CLASS_MODULE.CreateNewRobotxian(), it will actually run!

local BUILDER_CLASS_MODULE = setmetatable({}, {__index = ROBOTXIAN_MAIN})

PERSONALLY I don’t like doing it like that
I recommend simply just doing this.

This is also called “Object-level inheritance”

local BUILDER_CLASS_MODULE = {}
BUILDER_CLASS_MODULE.__index = BUILDER_CLASS_MODULE

-- in the CreateNewBuilderRobotxian function
local Robotxian = ROBOTXIAN_MAIN.CreateNewRobotxian()

And last thing, Luau technically doesn’t have OOP.
tables and metatables simulate it, sorta similarly
So things like Object-level inheritance, Class-level inheritance, don’t actually exist on Luau, they’re only patterns using tables and metatables.