Debounce not working

[ParkCityUSA (CityofPark)]

Hey! I’m scripting a javelin for a game, and everything seems to be running smoothly, except for one thing. I tried to make it so that once the javelin part recognizes it’s touching something with a humanoid in it, it will deal damage once and then never again. However, this is not the case; it continues to deal damage when touched, making the game very unbalanced. Here’s the code:

BulletClone.Touched:Connect(function(otherPart)
		
	local deb = false
			
	local hum = otherPart.Parent:FindFirstChild("Humanoid")
			
	if deb == false then	
				
		if hum then
			print("hit a humanoid")
			BulletClone.Parent = hum.Parent
			hum.Health = hum.Health - 10
			deb = true
		end
				
	end
	
	wait(5)

	BulletClone:Destroy()
	
end)

Sorry in case the formatting is messy. I’m probably forgetting something basic. Any help is appreciated!

[astrovue]

You don’t have a condition where you’re checking if your deb is set to true. Your code will continue executing.

-- Above your if condition,
if deb == true then
    return
end

[MrOnlyKemal]

Put the local deb = false outside the function, at the beginning of the code

[ParkCityUSA (CityofPark)]

Put an elseif in the statement and it worked like a charm. Thanks for catching my dumb error!

[astrovue]

No problem. Also, as @MrOnlyKemal said, you should place the deb boolean outside of your :Connect() method. And please use task.wait() from the task library instead of wait()!

[anime_bb]

@ParkCityUSA

it will deal damage once and then never again

In this case you would probably benefit more from a blacklist as opposed to a time-based debounce. When we successfully detect a humanoid, we can deal damage to it and also cache (i.e., remember) the instance to prevent acting on it twice:

local blacklist: { [Humanoid]: boolean }= {}; -- use keys instead to hasten lookups

BulletClone.Touched:Connect(function(hit)
	local hum = otherPart.Parent:FindFirstChildOfClass'Humanoid';

	if blacklist[hum] then return; end -- escape if this humanoid is already blacklisted

	blacklist[hum] = true; -- cache the new humanoid immediately

	-- handle hit logic
	print'hit a humanoid';
	hum:TakeDamage(10);
end

The way you’ve implemented BulletClone:Destroy() destroys the bullet five seconds after the first hit, which isn’t very intuitive. You can immediately add the bullet to debris outside of the event so that it has a predetermined lifespan:

local debris = game:GetService'Debris';

debris:AddItem(BulletClone, 5);