How necessary is "null" the variables?

[HerlySQR]

I heard you should "null" the variables when you don't need it anymore, but I saw people sometimes didn't do this when they recommend triggers, so when is necessary do this?

 

[Uncle]

[code=jass] - Integer Question

You don't need to null Integers and Reals. I may be forgetting some.

You do need to null Groups, Forces, Units, Points (Locations), etc... AFTER removing/destroying them.

I think you get an error in vJass if you try to null something that shouldn't be nulled.

 

[HerlySQR]

You do need to null Groups, Forces, Units, Points (Locations), etc... AFTER removing/destroying them.

I heard that, but I mean when some people who seem to know about the topic do not do this with that things, are they doing it wrong?, and Have I do this also with global variables and in GUI?

 

[Uncle]

I heard that, but I mean when some people who seem to know about the topic do not do this with that things, are they doing it wrong?, and Have I do this also with global variables and in GUI?

You only null local variables, and you need to do it in GUI as well.

Global variables will always have some value.

 

[HerlySQR]

You only null local variables, and you need to do it in GUI as well.

Global variables will always have some value.

Oh thank you, and one more question: I heard I have to avoid the "Do nothing" function, but I have to use it if I use the "If/Then/Else"(One action) function, Is it necessary?

 

[Uncle]

Oh thank you, and one more question: I heard I have to avoid the "Do nothing" function, but I have to use it if I use the "If/Then/Else"(One action) function, Is it necessary?

You can use:

• If (All Conditions are True) then do (Then Actions) else do (Else Actions)
  • If - Conditions
  • Then - Actions
  • Else - Actions

And no, it does nothing. I think it was needed a while back in the early days of wc3.

I really can't confirm or deny whether it's actually a bad thing.

 

[HerlySQR]

You can use:

• If (All Conditions are True) then do (Then Actions) else do (Else Actions)
  • If - Conditions
  • Then - Actions
  • Else - Actions

And no, it does nothing. I think it was needed a while back in the early days of wc3.

I really can't confirm or deny whether it's actually a bad thing.

I know I can do that, but that will make my trigger look less elegant, when I ask Is it necessary? I mean Is it necessary avoid that function?

 

[Razorclaw_X]

Do Nothing was necessary to complete an If-Then-Else function which you could only do one Action or Condition on them back during RoC (every section had to be filled with something, hence where Do Nothing comes in). TFT introduced the Multi version so it's no longer necessary.

And really it doesn't do anything, it doesn't matter if its there or not unless you're really that particular about not 'wasting' a process.

 

[SinisterLuffy]

They could have filled the else part with comments, so Do Nothing wasn't necessary back then. It is just that they did not realize this hehe.

 

[HerlySQR]

So I have to remake all the If/Then/Else to optimimize my map.

 

[Uncle]

So I have to remake all the If/Then/Else to optimimize my map.

I don't think you would even notice the difference.

 

[HerlySQR]

I don't think you would even notice the difference.

I wanna make my map the most possible optimized.

 

[BloodSoul]

Use "Comment" instead of "Do Nothing" if you're gonna use those single-lined statements.

• If ((Random integer number between 1 and 2) Equal to 1) then do (Player - Add 1 to (Triggering player) Current gold) else do (-------- --------)

 

[HerlySQR]

Use "Comment" instead of "Do Nothing" if you're gonna use those single-lined statements.

• If ((Random integer number between 1 and 2) Equal to 1) then do (Player - Add 1 to (Triggering player) Current gold) else do (-------- --------)

hmmm

 

[Razorclaw_X]

They could have filled the else part with comments, so Do Nothing wasn't necessary back then. It is just that they did not realize this hehe.

Well... about that... Comment didn't exist, either.

 

[HerlySQR]

Well... about that... Comment didn't exist, either.

Je

 

[HerlySQR]

One more question, if I don't wanna delete the handle I have to null the variable too?, exm:

Local unit u
u=GetAtacker()
call Wait(2.00)
set udg_Temp_Unit=u
call some_funct(udg_Temp_Unit)
u=null

Its ok?

 

[Uncle]

You only null local variables. So yes, you're doing it correctly there.

"local unit u" would exist forever in the game's memory if it wasn't nulled.

udg_Temp_Unit, a global variable, is intended to exist forever, so it doesn't need the same treatment.

• Example
  • Events
    • Unit - A unit enters (Entire map)
  • Conditions
  • Actions
    • Custom script: local unit u
    • Custom script: set u = GetTriggerUnit()
    • Custom script: set udg_Unit = u
    • Custom script: set u = null
    • Game - Display to (All players) for 30.00 seconds the text: (Name of Unit)

Using this trigger as an example:
I set u = the entering unit and I set udg_Unit = the entering unit.
I then null u and display the name of udg_Unit.
udg_Unit is pointing to the entering unit, not u, and will display the unit's name properly.
u has been successfully cleaned up and will return null.

 

[HerlySQR]

@Uncle Thank you

 

[HerlySQR]

Question: Do the orders leak or they count as string?

 

[HerlySQR]

After some reading I found:

type agent extends handle // all reference counted objects

So I guess the unique types those have the problem of reference count are agents, so those aren't agents don't need be nulled, am I right?

 

[Wrda]

Memory Leaks Again, this tutorial explains it all.
But yes, only agents need to be nulled (local variables only), you don't null strings, they will always leak, but once. Meaning that once a character is in the string table it won't leak anymore.

 

[HerlySQR]

Memory Leaks Again, this tutorial explains it all.
But yes, only agents need to be nulled (local variables only), you don't null strings, they will always leak, but once. Meaning that once a character is in the string table it won't leak anymore.

Oh I miss the word "agent", thank you.
If someone wanna know these aren't agents:

igamestate
image
itempool
itemtype
lightning
limitop
mapcontrol
mapdensity
mapflag
mapsetting
mapvisibility
pathingtype
placement
playercolor
playerevent
playergameresult
playerscore
playerslotstate
playerstate
playerunitevent
race
racepreference
raritycontrol
soundtype
startlocprio
terraindeformation
texmapflags
texttag
triggeraction
triggercondition
ubersplat
unitevent
unitpool
unitstate
unittype
version
volumegroup
weapontype
weathereffect
widgetevent

 

[Wrda]

Good stuff my man.

 

[IcemanBo]

There are more missing. All primitives, enums and handles that are not listed unter 'agent' are not agents JASS Manual: API Browser - Type handle.

It's easier to say what IS an agent, looking at JASS Manual: API Browser - Type agent.