Trying buffs help

[Trenix]

So because I'm working on a PvP mod, I need to start dealing with buffs. I used the buff API and I think I set it correctly for the most part, yet the game crashes. My biggest problem is how listen events work. It seems like you have to create a function to begin to listen, but to run the function, it has to be called by another function. That is why I tried using AddPlayerPostInit, yet whenever I tried to do any of this, it ALWAYS crashes. I don't know what I'm doing wrong. Please help.

---- [Slow Players Upon PvP Attack] ----
local function Applybuff(buffData, instToBuff)
	local buffUniqueName = buffData.uniqueName
	
	-- Cancel any existing duplicate timed buff.
	if instToBuff[buffUniqueName.."Task"] ~= nil then
		buffData.removeFunction(instToBuff)
		instToBuff[buffUniqueName.."Task"]:Cancel()
		instToBuff[buffUniqueName.."Task"] = nil
	end
	
	-- Make sure that our buff is removed BEFORE the entity is saved (the server is closed or player quits).
	-- This is only necessary if you change variables which are saved, like current health, health-penalty, etc.
	-- Without it, you could apply a max-health buff, quit before it ran out, rejoin, and you would have kept
	-- the extra max health!
	local buffOnSave = function(self, inst, data)
		if inst[buffUniqueName.."Task"] ~= nil then
			buffData.removeFunction(inst)
			inst[buffUniqueName.."Task"]:Cancel()
			inst[buffUniqueName.."Task"] = nil
		end
	end
	
	if instToBuff.OnSave ~= nil then
		local oldOnSave = instToBuff.OnSave
		instToBuff.OnSave = function(self, inst, data)
			buffOnSave(self, inst, data)
			oldOnSave(self, inst, data)
		end
	else
		instToBuff.OnSave = buffOnSave
	end
	
	-- Apply the buff.
	buffData.applyFunction(instToBuff)
	
	-- Set up removal after a certain amount of time.
	instToBuff[buffUniqueName.."Task"] = instToBuff:DoTaskInTime(buffData.duration, function(inst)
    buffData.removeFunction(inst)
    inst[buffUniqueName.."Task"] = nil
	end)
end
    
-- Now to make some buffs and put them in a Buffs-dictionary.
local Buffs = {}

-- This function creates a new buff-data object and adds it to the Buffs-dictionary
-- with the uniqueName as key.
local function CreateBuff(uniqueName, duration, applyFunction, removeFunction)
	local newBuff = {}
	newBuff.uniqueName = uniqueName
	newBuff.duration = duration
	newBuff.applyFunction = applyFunction
	newBuff.removeFunction = removeFunction
	Buffs[uniqueName] = newBuff
end

-- This is an example of how to use the CreateBuff() function to create a new buff.
CreateBuff("SlowDownPlayer", 3.0,
	function(inst)
    inst.components.locomotor:SetExternalSpeedMultiplier(inst, "Slow", 0.1)
  end,
  function(inst)
    inst.components.locomotor:RemoveExternalSpeedMultiplier(inst, "Slow")
	end)
end)

AddPlayerPostInit(function(inst)
	inst.ListenForEvent("attacked", function(inst,data) PVPATTACK(inst, data, false)
end)
	
local function PVPATTACK(inst,data)
	if 
		data.attack==nil or inst==nil
	then
	return
	end
	if
	data.attacker:HasTag("player")
	then
		print("It works")
	    ApplyBuff(Buffs["SlowDownPlayer"], data.attacker)
	end
end

 

[Trenix]

Alright so I figured it out, Applybuff should of been ApplyBuff and inst.ListenForEvent should of been inst:ListenForEvent. The effect works but I'm having trouble applying it to the right person. Seems like everyone always applies stuff to the attacker, but how do you get data on the person who is attacked?

[Trenix]

Nevermind, the inst in the attacked event is the player who was attacked. The data.attacker is obviously the attacker. Here is the code for people who are trying to do something similar.

AddPlayerPostInit(function(inst)
	inst:ListenForEvent("attacked", function(inst, data)
		if inst==nil or data.attacker==nil
		then
		return
		end
		if
			inst:HasTag("player") and data.attacker:HasTag("player")
		then
			ApplyBuff(Buffs["SlowDownPlayer"], inst)
		end
	end)
end)

For here, the buff I'm applying only effects PvP interaction. The attack and the player who is attacked, both have to be actual players.