Strict Object-Oriented Method Overloading

[scar2056]

Implementation:

--!strict

local ClassName = {}
ClassName.__index = ClassName

function ClassName.new()
	local self = setmetatable({}, ClassName)
	self._privateProperty = nil :: Vector3?
	return self
end

type ClassName = typeof(ClassName.new())

-- doc comment vector2
function ClassName.OverloadVector2(self: ClassName, value: Vector2): Vector2
	return value
end

-- doc comment vector3
function ClassName.OverloadVector3(self: ClassName, value: Vector3): Vector3
	return value
end

ClassName.Overload = function(self: ClassName, arg1: any): any
	if typeof(arg1) == "Vector2" then
		return self:OverloadVector2(arg1)
	elseif typeof(arg1) == "Vector3" then
		return self:OverloadVector3(arg1)
	end
	error("Arguments did not match any overload.")
end
:: typeof(ClassName.OverloadVector2)
 & typeof(ClassName.OverloadVector3)

Usage 1:

local className = ClassName.new()

local raycastResult = workspace:Raycast(Vector3.new(), Vector3.new())

if raycastResult then
	local v3r = className:Overload(raycastResult.Position)
	Vector3.new():Lerp(v3r, 1);
end

Type Error: Type 'Vector2' could not be converted into 'Vector3'

Replacing raycastResult.Position with raycastResult.Position :: Vector3 removes the error, but should not be necessary. Hovering the cursor over v3r displays the type as Vector3 regardless of whether this casting is done.

When an overload is called with a colon syntax, placing the I-cursor inside the function will always display the first overload.