Turns events into vars instead of a list, to greatly simplify qdel() cleanup.

baystation12.dme

@@ -122,7 +122,6 @@
 #include "code\controllers\subsystems.dm"
 #include "code\controllers\verbs.dm"
 #include "code\controllers\voting.dm"
-#include "code\controllers\observer_listener\datum\observer.dm"
 #include "code\controllers\Processes\air.dm"
 #include "code\controllers\Processes\alarm.dm"
 #include "code\controllers\Processes\chemistry.dm"
@@ -212,6 +211,7 @@
 #include "code\datums\helper_datums\global_iterator.dm"
 #include "code\datums\helper_datums\teleport.dm"
 #include "code\datums\helper_datums\topic_input.dm"
+#include "code\datums\observation\observation.dm"
 #include "code\datums\wires\airlock.dm"
 #include "code\datums\wires\alarm.dm"
 #include "code\datums\wires\apc.dm"

code/controllers/Processes/scheduler.dm

@@ -28,16 +28,13 @@
 	stat(null, "[scheduled_tasks.len] task\s")
 
 /datum/controller/process/scheduler/proc/schedule(var/datum/scheduled_task/st)
-	if(world.time < st.trigger_time)
-		scheduled_tasks += st
-		st.register(OBSERVER_EVENT_DESTROY, src, /datum/controller/process/scheduler/proc/unschedule)
-	else
-		st.process()
+	scheduled_tasks += st
+	st.destruction.register(src, /datum/controller/process/scheduler/proc/unschedule)
 
 /datum/controller/process/scheduler/proc/unschedule(var/datum/scheduled_task/st)
 	if(st in scheduled_tasks)
 		scheduled_tasks -= st
-		st.unregister(OBSERVER_EVENT_DESTROY, src)
+		st.destruction.unregister(src)
 
 /**********
 * Helpers *
@@ -98,7 +95,7 @@
 
 /datum/scheduled_task/source/New(var/trigger_time, var/datum/source, var/procedure, var/list/arguments, var/proc/task_after_process, var/list/task_after_process_args)
 	src.source = source
-	src.source.register(OBSERVER_EVENT_DESTROY, src, /datum/scheduled_task/source/proc/source_destroyed)
+	src.source.destruction.register(src, /datum/scheduled_task/source/proc/source_destroyed)
 	..(trigger_time, procedure, arguments, task_after_process, task_after_process_args)
 
 /datum/scheduled_task/source/Destroy()

code/controllers/observer_listener/datum/observer.dm

@@ -1,41 +0,0 @@
-#define OBSERVER_EVENT_DESTROY "OnDestroy"
-
-/datum
-	var/list/observer_events
-
-/datum/Destroy()
-	raise_event(OBSERVER_EVENT_DESTROY, list(src))
-	for(var/list/listeners in observer_events)
-		listeners.Cut()
-
-	return ..()
-
-/datum/proc/register(var/event, var/procOwner, var/proc_call)
-	var/list/listeners = get_listener_list_from_event(event, TRUE)
-	listeners[procOwner] = proc_call
-
-/datum/proc/unregister(var/event, var/procOwner)
-	var/list/listeners = get_listener_list_from_event(event, FALSE)
-	listeners -= procOwner
-
-/datum/proc/raise_event(var/event, var/list/args = list())
-	var/list/listeners = get_listener_list_from_event(event, FALSE)
-	if(listeners)
-		for(var/listener in listeners)
-			call(listener, listeners[listener])(arglist(args))
-
-/datum/proc/get_listener_list_from_event(var/observer_event, var/create_list)
-	if(!observer_events)
-		if(create_list)
-			observer_events = list()
-		else
-			return
-
-	var/list/listeners = observer_events[observer_event]
-	if(!listeners)
-		if(create_list)
-			listeners = list()
-			observer_events[observer_event] = listeners
-		else
-			return
-	return listeners

code/datums/observation/observation.dm

@@ -0,0 +1,56 @@
+/datum/observ
+	var/list/listeners
+
+/datum/observ/Destroy()
+	if(listeners)
+		for(var/listener in listeners)
+			unregister(listener)
+		listeners.Cut()
+	return ..()
+
+/datum/observ/proc/register(var/datum/procOwner, var/proc_call)
+	if(!listeners)
+		listeners = list()
+	listeners[procOwner] = proc_call
+	procOwner.destruction.register(src, /datum/observ/proc/unregister)
+
+/datum/observ/proc/unregister(var/datum/procOwner)
+	if(!listeners)
+		return
+	listeners -= procOwner
+	procOwner.destruction.unregister(src)
+
+/datum/observ/proc/raise_event(var/list/args = list())
+	if(!listeners)
+		return
+	for(var/listener in listeners)
+		call(listener, listeners[listener])	(arglist(args))
+
+/***********************
+* Destruction Handling *
+***********************/
+/datum
+	var/datum/observ/destruction
+
+/datum/New()
+	init_observers()
+	..()
+
+/datum/Destroy()
+	destruction.raise_event(list(src))
+	destroy_observers()
+	return ..()
+
+/datum/proc/init_observers()
+	destruction = new()
+
+/datum/proc/destroy_observers()
+	qdel(destruction)
+	destruction = null
+
+// This ensures that observer handlers don't create their own observer handlers, which create their own handlers, which create...
+/datum/observ/init_observers()
+	return
+
+/datum/observ/destroy_observers()
+	return

code/game/machinery/computer/station_alert.dm

@@ -38,7 +38,7 @@
 
 /obj/machinery/computer/station_alert/proc/unregister_monitor()
 	if(alarm_monitor)
-		alarm_monitor.unregister(src)
+		alarm_monitor.unregister_alarm(src)
 		qdel(alarm_monitor)
 		alarm_monitor = null
 

code/game/objects/items/devices/hacktool.dm

@@ -17,7 +17,7 @@
 /obj/item/device/multitool/hacktool/Destroy()
 	for(var/T in known_targets)
 		var/atom/target = T
-		target.unregister(OBSERVER_EVENT_DESTROY, src)
+		target.destruction.unregister(src)
 	known_targets.Cut()
 	qdel(hack_state)
 	hack_state = null
@@ -68,7 +68,7 @@
 		return 0
 
 	known_targets.Insert(1, target)	// Insert the newly hacked target first,
-	target.register(OBSERVER_EVENT_DESTROY, src, /obj/item/device/multitool/hacktool/proc/on_target_destroy)
+	target.destruction.register(src, /obj/item/device/multitool/hacktool/proc/on_target_destroy)
 	return 1
 
 /obj/item/device/multitool/hacktool/proc/sanity_check()
@@ -77,7 +77,7 @@
 	if(known_targets.len > max_known_targets)
 		for(var/i = (max_known_targets + 1) to known_targets.len)
 			var/atom/A = known_targets[i]
-			A.unregister(OBSERVER_EVENT_DESTROY, src)
+			A.destruction.unregister(src)
 		known_targets.Cut(max_known_targets + 1)
 
 /obj/item/device/multitool/hacktool/proc/on_target_destroy(var/target)

code/game/objects/items/devices/multitool.dm

@@ -48,13 +48,13 @@
 			unregister_buffer(buffer_object)
 			buffer_object = buffer
 			if(buffer_object)
-				buffer_object.register(OBSERVER_EVENT_DESTROY, src, /obj/item/device/multitool/proc/unregister_buffer)
+				buffer_object.destruction.register(src, /obj/item/device/multitool/proc/unregister_buffer)
 
 /obj/item/device/multitool/proc/unregister_buffer(var/atom/buffer_to_unregister)
 	// Only remove the buffered object, don't reset the name
 	// This means one cannot know if the buffer has been destroyed until one attempts to use it.
 	if(buffer_to_unregister == buffer_object && buffer_object)
-		buffer_object.unregister(OBSERVER_EVENT_DESTROY, src)
+		buffer_object.destruction.unregister(src)
 		buffer_object = null
 
 /obj/item/device/multitool/resolve_attackby(atom/A, mob/user)

code/game/objects/items/weapons/cards_ids_syndicate.dm

@@ -66,13 +66,13 @@
 	unset_registered_user()
 	registered_user = user
 	user.set_id_info(src)
-	user.register(OBSERVER_EVENT_DESTROY, src, /obj/item/weapon/card/id/syndicate/proc/unset_registered_user)
+	user.destruction.register(src, /obj/item/weapon/card/id/syndicate/proc/unset_registered_user)
 	return TRUE
 
 /obj/item/weapon/card/id/syndicate/proc/unset_registered_user(var/mob/user)
 	if(!registered_user || (user && user != registered_user))
 		return
-	registered_user.unregister(OBSERVER_EVENT_DESTROY, src)
+	registered_user.destruction.unregister(src)
 	registered_user = null
 
 /obj/item/weapon/card/id/syndicate/CanUseTopic(mob/user)