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Is my Lua object going to?

Warning:

Now I am convinced that the problem is that the luatraverse script described here does not work as advertised, and does not find all references to the object. In my example, I found where the object was referencing, thereby preventing its collection, but this was not reported script.

Therefore, the basic premise of this issue is somewhat flawed.

Feedback:

I am working on improving the scripting engine in Bitfighter . I'm not sure that memory is being freed properly. Therefore, I built the test as a script below.

It prints 3 columns of userdatas. Column 1 is the user data, which I expect to not use anymore, and therefore should be destroyed by the collectgarbage function. Columns 2 and 3 are objects that I think should not be collected, because I hold them in my hands.

Problem:

The user data in column 1 never changes, so I suspect it is not going to (cols. 2 and 3 behave as expected). To clarify the situation, I am using the luatraverse script mentioned in this problem , which seems to confirm that there is only one link to obj100, which is stored in obj100. I tried to add an assignment just before running countreferences (local x = obj100), and, as expected, countreferences reported that the object was referenced twice.

Questions:

1) obj100 ? , ?

2) , luatraverse script, , Lua?

:

 -- Every 2 seconds, find two objects with ids 100 and 200, and print their addrs
 -- No reference is kept for object 100, so its userdata might change over time
 -- Object 200 is held by objHolder, so its userdata should remain constant

 -- Obj200 should remain constant over time; obj100 can vary.  
 -- objHolder should be constant, obviously

 local ltraverse = require("luatraverse")


 function printIds()
    local obj100 = levelgen:findObjectById(100)
    local obj200 = levelgen:findObjectById(200)
    print("Obj 100:" .. tostring(obj100) .. " Obj 200:" .. 
           tostring(obj200) .. " Held:" .. tostring(objHolder))


    print(ltraverse.countreferences(obj100))

    obj100 = nil
    obj200 = nil

    collectgarbage()
 end

 function main()
    -- levelgen:findObjectById is a local game command that
    -- creates a userdata for an object
    local obj100 = levelgen:findObjectById(100)
    objHolder    = levelgen:findObjectById(200)     -- not local, global

    assert(obj100)
    assert(objHolder)

    print("Column 1 can vary; 2 and 3 should be constant")
    print("=============================================")

    print("Obj 100:" .. tostring(obj100) .. " Obj 200:" .. 
         tostring(objHolder) .. " Held:" .. tostring(objHolder))

    obj100 = nil

    -- Run a function every 2 seconds
    Timer:scheduleRepeating(printIds, 2000)
 end

:

 Column 1 can vary; 2 and 3 should be constant
 =============================================
 Obj 100:userdata: 02FC9700 Obj 200:userdata: 02FAD280 Held:userdata: 02FAD280

 Obj 100:userdata: 02FC9700 Obj 200:userdata: 02FAD280 Held:userdata: 02FAD280
 1
 Obj 100:userdata: 02FC9700 Obj 200:userdata: 02FAD280 Held:userdata: 02FAD280
 1
 Obj 100:userdata: 02FC9700 Obj 200:userdata: 02FAD280 Held:userdata: 02FAD280
 1
 Obj 100:userdata: 02FC9700 Obj 200:userdata: 02FAD280 Held:userdata: 02FAD280
 1
 Obj 100:userdata: 02FC9700 Obj 200:userdata: 02FAD280 Held:userdata: 02FAD280
 1
 ... and onward to infinity ...
+1
1

Bitfighter, , :

user Lata Lua, ++ (?):

local obj100 = levelgen:findObjectById(100)

Lua (obj100, ):

print(ltraverse.countreferences(obj100))

1, .

reference/Lua, , , . userdata () , . , / - .

, , , , levelgen:findObjectById(). , ?

local temp
local obj100 = temp = levelgen:findObjectById(100)
0

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