Thanks for helping at the THW chat!
(topic: "boolexpr")
// reminded me to an alternativ function i completely forgot:
// regarding this event:
native TriggerRegisterEnterRegion takes trigger whichTrigger, region whichRegion, boolexpr filter returns event
// instead of using a boolexpr there like (look for var "b"):
call TriggerRegisterEnterRegion(t, r, b)
// you can use:
call TriggerRegisterEnterRegion(t, r, null)
// together with:
native TriggerAddCondition takes trigger whichTrigger, boolexpr condition returns triggercondition
// like:
call TriggerAddCondition(t, Filter(function Condition_Player))
// this was necessary for me,
// because i need to use the event response variable "GetTriggeringRegion()" in the boolexpr function.
// for "TriggerAddCondition" it returns a value, but for "TriggerRegisterEnterRegion" it always returns null!