Calling list immediately after creating a trigger via createTrigger (and setting up activation, area, statements, timeout, etc..), will return <null> instead of an array. It seems the trigger needs about 1 second to initialise, after which it will behave as expected: returning an array of all the objects inside the trigger (the ones matching the criteria), or an empty array.
Description
List of units that would activate given Trigger.
It returns nothing before the simulation started, i.e. in (undelayed) init.sqf files. Returns a pointer to the trigger's list after the simulation started.
Since this is just a reference this means that the value in your local variable will change as the content of the trigger area changes.
To permanently copy the returned list to a different variable, use _mylist = +(list triggerOne).
The second example can be used inside the trigger (in that case, no need to name your trigger).
The list returned for trigger of type "Not present" is the same as that returned for type "present".
Important
While the command can query any trigger, local or remote, the result will be only for the trigger condition set on the local client. See createTrigger for more info.
Syntax
list trigger
Parameters:
trigger: Object
Returns: Nothing or Array of Objects
Examples
Example 1
_triggerList = list _triggerOne;
Example 2
hint format ["%1", thisList];
See also
setTriggerActivation · createTrigger · thisList
Community notes
The resulting array is not modifiable. Any array related commands, that modify the original array, will fail with the error message: Error Reserved variable in expression.