How would I go about creating methods for objects?

Help and Feedback Scripting Support
#1

This is something that you can do in Java so I was wondering if you can do it here.

Let’s say I have a IntValue and I want to create a method for it

function IntValue:Add(number)
  self.Value += number
end

TestingValue:Add(2)

That’s just a visual representation of what I’m trying to achieve, does anyone know any methods? I tried metatables but it isn’t quite what I need.

1 Like
#2

Absolutely! While it isn’t supported by default in lua, there are some tricks

Link to full article: (Suggested Read) All about Object Oriented Programming - Resources / Community Tutorials - DevForum | Roblox

Here is an example:

local Car = {}
Car.__index = Car

function Car.new(carColor)
    local self = {}
    self.color = carColor
    return setmetatable(self, Car)
end

function Car:GetColor()
    return self.color
end

local carObj = Car.new("blue")
print(carObj:GetColor()) -- Returns blue
#3

Thank you very much, it appears metatables were the way to go.

1 Like
#4

By any chance, is there any way to implemented these custom methods to already existing Roblox objects, such as IntValues?

#5

I’m pretty sure default roblox instances and such are read-only, however, you can make wrapper classes. Such as

local inst = Instance.new("IntValue")

local IntWrapper = {}

function IntWrapper.new(objToWrap)
	local self = {}
	
	return setmetatable(self,
		{__index = function(obj, key)
			return IntWrapper[key] or objToWrap[key]
		end})
end

function IntWrapper:GetValue()
	return self.Value
end

local int = IntWrapper.new(Instance.new("IntValue"))
print(int:GetValue(), int.Value) -- Both return 0, as that is the default value for IntValue's

Although the code may look overwhelming