Question about garbage-collection

There might be an obvious answer for this, but I still wanna ask

local b = 2

do -- new scope
	local x = 2

	print(x)
end
-- is the scope garbage-collected afterwards?
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yes, in lua, local variables defined within a do ... end block are subject to lua’s garbage collection once the block completes execution. this ensures that memory used by these variables is reclaimed when they are no longer needed.

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i see, but does this only apply to do statements? like would this work in these conditions:

if 1+1 == 2 then -- is this a new scope?
	local b = 2
	print(b)
end
for i = 1, 5 do -- is this also a new scope?
	local heyguys = 2
	print(heyguys)
end

Yes. Try and print(heyguys) out of the scope, you’ll notice Roblox will underline in orange because the reference doesn’t exist there. Therefore, the output will be nil.

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Yes, the scope created by the do ... end block is indeed garbage-collected after it is executed. In Lua, local variables defined within a block (such as a do ... end block) are only accessible within that block. Once the block is exited, those variables go out of scope and are eligible for garbage collection if there are no other references to them.

In your example:

local b = 2

do -- new scope
	local x = 2

	print(x) -- prints 2
end
  • The variable x is local to the do ... end block.
  • After the do ... end block is executed, the variable x goes out of scope.
  • Since x is no longer accessible and there are no references to it, it becomes eligible for garbage collection.

This is an important feature of Lua’s memory management, which helps in efficiently managing memory by automatically cleaning up variables that are no longer needed.

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