Can't understand why I get attempted to index global "self" ( a nil value )

[jellofacey]

Yeah, i've been trying to figure out what im doing wrong right now, i keep getting "attempted to index global "-" a nil value
The script is supposed to let the player slide when he holds down Forward and ducks, but i cant seem to figure out why it gives me the error stated, i tried searching and all that but the solutions are for a very specific scenario and they dont seem to work on my script.

my script is a autorun script

local ply = self.Owner
hook.Add( "Tick", "Slide", function()
if ply:WaterLevel() <= 1 then
	if !IsValid( ply ) then return end
	local pos = self:GetOperatingPoint()
	
		ply.SlidingSound = ply.SlidingSound or CreateSound( ply, 'slidemod/floorslide.wav' )
		if ply:KeyDown( IN_FORWARD ) and ply:KeyDown( IN_DUCK ) and ply:IsOnGround() then 
		if ply:GetVelocity():Length() < 150 then if ply.SlidingSound:IsPlaying() then ply.SlidingSound:Stop() end return end
		ply.SlideVelocity = ply.SlideVelocity or 0
		if ply.SlideVelocity == 0 then ply.SlideVelocity = 70 * ( math.Clamp( ply:GetVelocity():Length() / 500, 0, 1 ) ) end
	
	local dir = Angle( 0, ply:EyeAngles().y, 0 ):Forward()
	local tr = util.TraceLine( { start = pos, endpos = pos + dir * 35, filter = ply } )
	local tr_up = util.TraceLine( { start = pos - Vector( 0, 0, 40 ), endpos = pos - Vector( 0, 0, 43 ) + dir * 25, filter = ply } )
	local tr_down = util.TraceLine( { start = pos - Vector( 0, 0, 40 ), endpos = pos - Vector( 0, 0, 48 ) + dir * 25, filter = ply } )
	
	if !tr_down.Hit then ply.SlideVelocity = math.Approach( ply.SlideVelocity, 100, 0.5 ) else ply.SlideVelocity = math.Approach( ply.SlideVelocity, 0, 0.5 ) end
	
	if tr_up.Hit then ply.SlideVelocity = math.Approach( ply.SlideVelocity, 0, 2 ) end
	if tr.Hit and ply.SlideVelocity > 0 then
		if IsValid( tr.Entity ) and ( tr.Entity:IsPlayer() or tr.Entity:IsNPC() ) then tr.Entity:TakeDamage( 70 * ( math.Clamp( ply:GetVelocity():Length() / 1000, 0, 1 ) ), self.Owner, self ) end
		ply:ViewPunch( Angle( ply.SlideVelocity / 5, 0.3, -1 ) )
		ply.SlideVelocity = 0
		if ply.SlidingSound:IsPlaying() then ply.SlidingSound:Stop() ply:EmitSound( 'slidemod/floorslide_hit_hard.wav' ) end
		return
	end
	
	ply:ViewPunch( Angle( 0, 0.3, -1 ) )
	ply:SetVelocity( dir * ply.SlideVelocity )
	if !ply.SlidingSound:IsPlaying() then ply.SlidingSound:Play() end
	else ply.SlideVelocity = 0 if ply.SlidingSound and ply.SlidingSound:IsPlaying() then ply.SlidingSound:Stop() end
	end
end
end )

[Rmk123]

Post your error please

[jellofacey]

[QUOTE=Rmk123;48162867]Post your error please[/QUOTE]

[ERROR] addons/sliding/lua/autorun/slide.lua:1: attempt to index global 'self' (a nil value)
1. unknown - addons/sliding/lua/autorun/slide.lua:1

[Carlton Dance]

You haven't defined ply properly. Self is nil in other words nothing. You'll have to retrieve the player somehow else.

[LegendofRobbo]

[QUOTE=jellofacey;48162861]Yeah, i've been trying to figure out what im doing wrong right now, i keep getting "attempted to index global "-" a nil value
The script is supposed to let the player slide when he holds down Forward and ducks, but i cant seem to figure out why it gives me the error stated, i tried searching and all that but the solutions are for a very specific scenario and they dont seem to work on my script.

my script is a autorun script

local ply = self.Owner
hook.Add( "Tick", "Slide", function()
if ply:WaterLevel() <= 1 then
	if !IsValid( ply ) then return end
	local pos = self:GetOperatingPoint()
	
		ply.SlidingSound = ply.SlidingSound or CreateSound( ply, 'slidemod/floorslide.wav' )
		if ply:KeyDown( IN_FORWARD ) and ply:KeyDown( IN_DUCK ) and ply:IsOnGround() then 
		if ply:GetVelocity():Length() < 150 then if ply.SlidingSound:IsPlaying() then ply.SlidingSound:Stop() end return end
		ply.SlideVelocity = ply.SlideVelocity or 0
		if ply.SlideVelocity == 0 then ply.SlideVelocity = 70 * ( math.Clamp( ply:GetVelocity():Length() / 500, 0, 1 ) ) end
	
	local dir = Angle( 0, ply:EyeAngles().y, 0 ):Forward()
	local tr = util.TraceLine( { start = pos, endpos = pos + dir * 35, filter = ply } )
	local tr_up = util.TraceLine( { start = pos - Vector( 0, 0, 40 ), endpos = pos - Vector( 0, 0, 43 ) + dir * 25, filter = ply } )
	local tr_down = util.TraceLine( { start = pos - Vector( 0, 0, 40 ), endpos = pos - Vector( 0, 0, 48 ) + dir * 25, filter = ply } )
	
	if !tr_down.Hit then ply.SlideVelocity = math.Approach( ply.SlideVelocity, 100, 0.5 ) else ply.SlideVelocity = math.Approach( ply.SlideVelocity, 0, 0.5 ) end
	
	if tr_up.Hit then ply.SlideVelocity = math.Approach( ply.SlideVelocity, 0, 2 ) end
	if tr.Hit and ply.SlideVelocity > 0 then
		if IsValid( tr.Entity ) and ( tr.Entity:IsPlayer() or tr.Entity:IsNPC() ) then tr.Entity:TakeDamage( 70 * ( math.Clamp( ply:GetVelocity():Length() / 1000, 0, 1 ) ), self.Owner, self ) end
		ply:ViewPunch( Angle( ply.SlideVelocity / 5, 0.3, -1 ) )
		ply.SlideVelocity = 0
		if ply.SlidingSound:IsPlaying() then ply.SlidingSound:Stop() ply:EmitSound( 'slidemod/floorslide_hit_hard.wav' ) end
		return
	end
	
	ply:ViewPunch( Angle( 0, 0.3, -1 ) )
	ply:SetVelocity( dir * ply.SlideVelocity )
	if !ply.SlidingSound:IsPlaying() then ply.SlidingSound:Play() end
	else ply.SlideVelocity = 0 if ply.SlidingSound and ply.SlidingSound:IsPlaying() then ply.SlidingSound:Stop() end
	end
end
end )

[/QUOTE]

you can't use self in an autorun script, self only works inside entities or metafunctions

try using a for loop to run that logic on all players

[bitches]

self refers to the table object a function is running on

for example,

[lua]
mytable = {}
mytable.penis = 1
function mytable:MorePenis()
self.penis = self.penis+1
end
[/lua]

self is only valid in a function running off of a table object

[jellofacey]

oh now i get it, ill try what robbo suggested, thanks