Metatable __mode not working as expected

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1

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local weakTable = setmetatable({}, { __mode = "k" })

local function createObject(name)
	return { name = name }
end


local obj1 = createObject("Objeto 1")
local obj2 = createObject("Objeto 2")


weakTable[obj1] = "Este é o objeto 1"
weakTable[obj2] = "Este é o objeto 2"


obj1 = nil

for k, v in pairs(weakTable) do
	print(k, v)
end

I wonder if the __mode metatable has been disabled in Roblox Studio.

2

I think you need to wait for the garbage collector to run. Try adding a wait() to your code before you print the table out.

1 Like
3

As said above, you need to wait until the next gc cycle

local weakTable = setmetatable({}, { __mode = "k" })

local function createObject(name)
	return { name = name }
end


local obj1 = createObject("Objeto 1")
local obj2 = createObject("Objeto 2")


weakTable[obj1] = "Este é o objeto 1"
weakTable[obj2] = "Este é o objeto 2"


obj1 = nil

local n = 0

while true do
	n = 0
	
	for _ in weakTable do
		n += 1
	end
	
	if n >= 2 then
		task.wait()
	else
		break
	end
end

print('gc finished', weakTable) -- ok