I haven't read through the whole thread, but yes #1 should work.
It would look like:
Even though
TriggerExecute runs things on a new "thread", it is scheduled right away. After the trigger-action fully completes, it goes back to run
call this.destroy().
The only issue to worry about is recursion. Let's say you have a situation like this:
JASS:
struct Example
private static trigger eventTrigger = CreateTrigger()
static integer data = 0
static method fireEvent takes nothing returns nothing
set data = data + 1
call TriggerExecute(eventTrigger)
endmethod
static method registerAction takes code c returns nothing
call TriggerAddAction(eventTrigger, c)
endfunction
endstruct
// ...
function Callback takes nothing returns nothing
call BJDebugMsg("data: " + I2S(Example.data))
if Example.data == 0 then
call Example.fireEvent()
endif
call BJDebugMsg("data: " + I2S(Example.data))
endfunction
// start here
function Init takes nothing returns nothing
call Example.registerAction(function Callback)
call Example.fireEvent()
endfunction
This code looks pretty ugly and is contrived, but Example.data shows the problem. If you fire the event within a callback (recursively), then your instance "data" could've changed after it was called. So in this case, it would print:
"data: 0" (from the fireEvent in Init)
"data: 1" (from the fireEvent in Callback)
"data: 1" (from the fireEvent in Callback)
"data: 1" (from the fireEvent in Init)
Ideally, we would want it to print:
"data: 0"
"data: 1"
"data: 1"
"data: 0"
Basically, "data" should go back to its old value after the .fireEvent() is called in Callback. There are a couple of ways to approach this problem. All of them are pretty easy:
- Just use locals to store "Example.data" at the top of your function callbacks. That way you won't really have to worry about "Example.data" changing, since you'll always keep your own local value.
- Maintain some sort of stack.
- There is a nice little trick that Nestharus used to get around this. Just use a temporary variable when you fire the trigger:
JASS:
static method fireEvent takes nothing returns nothing
local integer oldValue = data
set data = data + 1
call TriggerExecute(eventTrigger)
set data = oldValue
endmethod
It is a bit of a pain to go through why this works, but if you follow the code through, it'll store "0" as the oldValue, set the data to 1, and when that thread finishes it'll restore the data value to "0".
You don't really have to worry about this
that much. But it is a tiny change that will prevent some despair later if you accidentally run into that problem. If you want to store multiple variables for the trigger to access, you would do the same thing. Just use one more temp variable for each variable.
