Forum

CS2D

Scripts

[Lua Problem] Weird table issue

Forums overview CS2D overview Scripts overview Log in to reply

[Lua Problem] Weird table issue

10 replies

[Lua Problem] Weird table issue

EngiN33R OP
Moderator Off

Offline

25.05.11 02:53:51 pm

So here's a code snippet:

1
2
3
4
5
6
7
8
9
10

addhook("kill","repchange")
function repchange(id,src)
	reputation[src][faction[id]]=reputation[src][faction[id]]-1
	for _,f in ipairs(factions[faction[id]].allies) do --line 125
		reputation[src][allies[f]]=reputation[src][allies[f]]-0.5
	end
	for _,f in ipairs(factions[faction[id]].enemies) do
		reputation[src][factions[faction[id]].enemies[f]]=reputation[src][factions[faction[id]].enemies[f]]-0.5
	end
end

After I kill a bot with ID 2 whose faction is 4 (faction[2]==4), it gives me the following error:

CS2D Console has written

LUA ERROR: sys/lua/space_rpg/main.lua:125: bad argument #1 to ipairs (table expected, got nil)

The table:

1
2
3
4
5
6
7
8
9
10
11

factions = {
--........
[4] = {
        name = "TeleTec Inc.",
        initrep = 10,
        tag = "[TEL]",
	allies = {1,2,3},
	enemies = {5},
},
--........
}

I have NO idea what's wrong with this thing. Halp?

Re: [Lua Problem] Weird table issue

Lee
Moderator Off

Offline

25.05.11 03:06:55 pm

for _,f in ipairs(factions[faction[id]].allies) do

The inner parameter should be factions[faction[id]].tag.allies

for _,f in ipairs(factions[faction[id]].enemies) do

Same here, .tag.enemies

PS: tables are always held as references, so if you alias a table, IE:

1
2

original = {1, 2, 3}
alias = original

Then all changes made on the alias will reflect back in the original as both references the same table in memory. This makes it easy to have temporary variables for deep nested tables:

1
2

local e = factions[faction[id]].enemies
...

Re: [Lua Problem] Weird table issue

EngiN33R OP
Moderator Off

Offline

25.05.11 03:39:34 pm

But factions[faction[id]].tag is one thing and factions[faction[id]].allies and enemies are completely another things. The post parser thing just messed up me tabs. .tag is "[TEL]" (string) and .allies and .enemies are different tables.

And I tried the local tables thingy, it doesn't work either.

Re: [Lua Problem] Weird table issue

Lee
Moderator Off

Offline

25.05.11 06:47:28 pm

Well, that's strange, since your error is

LUA ERROR: sys/lua/space_rpg/main.lua:125: bad argument #1 to ipairs (table expected, got nil)

, this means that the index was valid, meaning that factions[faction[id]] is a table. Can you post your entire structure up?

If you're hand coding the factions table, can you post the entire table? If not, one of the other operations most likely corrupted the structure of your table.

Add https://github.com/leegao/see.lua/raw/master/see.lua into the root cs2d folder and at the top of your script, add

1
2
3
4
5
6
7
8
9

require "see"

local __old_print = print
function print(...)
	local args = {...}
	for _,text in ipairs(args) do
		__old_print(tostring(text))
	end
end

and right before line 125, add

see(factions)

and post what's printed out

Re: [Lua Problem] Weird table issue

EngiN33R OP
Moderator Off

Offline

26.05.11 03:57:38 am

Whole code of the script kill hook's in: http://pastebin.com/xh3VBcKY

Whole code of the factions table: http://pastebin.com/SxMm9pKU

This is what was printed out:

CS2D Console has written

{{}, {}, {}, {}, {}, {}}

Though when I use print, it shows me that factions is a table, and that factions[1] is a table, and that factions[1].allies is also a table. It's really weird, I'm telling ya.

Re: [Lua Problem] Weird table issue

Lee
Moderator Off

Offline

26.05.11 05:06:59 am

That's actually expected, non-numerical indices are not shown in the subexpressions, so you can use see(factions[0]) to see the full fields.

If you try to index into factions[0].enemies, you will get an error seeing as that field doesn't exist. Since you've never changed the values of the faction table from all zeros, any time you have factions[faction[id]], it will evaluate to factions[0], and hence the above problem.

Re: [Lua Problem] Weird table issue

EngiN33R OP
Moderator Off

Offline

26.05.11 05:10:23 am

But I changed faction[2] to 4 and I was indexing factions[faction[2]].enemies, meaning it's factions[4].enemies. Either that, or I misunderstood you.

Re: [Lua Problem] Weird table issue

Lee
Moderator Off

Offline

26.05.11 05:28:54 am

Wait, so is factions[4].enemies a table? Doesn't that effectively solve your problem then?

Re: [Lua Problem] Weird table issue

EngiN33R OP
Moderator Off

Offline

26.05.11 05:48:25 am

Derp. It doesn't because it somehow causes the problem.

See, what I'm doing is:

execute script

add bot with ID 2

lua faction[2]=4

kill bot with ID 2

receive error

That's why I'm asking because I can't understand what is the cause of this damn thing.

Re: [Lua Problem] Weird table issue

Lee
Moderator Off

Offline

26.05.11 04:06:27 pm

kill hooks' first parameter is your (the killer's) id

Re: [Lua Problem] Weird table issue

EngiN33R OP
Moderator Off

Offline

26.05.11 05:21:55 pm

Oh. My. God. Derp

Worked like a charm when I changed places of the arguments. Thanks a lot.