tiny optimisation

code/_helpers/typelists.dm

@@ -0,0 +1,43 @@
+GLOBAL_LIST_EMPTY(typelists)
+
+#ifndef TESTING
+
+/datum/proc/typelist(key, list/values = list())
+	var/list/mytypelist = GLOB.typelists[type] || (GLOB.typelists[type] = list())
+	return mytypelist[key] || (mytypelist[key] = values.Copy())
+
+#else
+// mostly the same code as above, just more verbose, slower and has tallying for saved lists
+/datum/proc/typelist(key, list/values)
+	if (!values)
+		values = list()
+	GLOB.typelistkeys |= key
+	if (GLOB.typelists[type])
+		if (GLOB.typelists[type][key])
+			GLOB.typelists[type]["[key]-saved"]++
+			return GLOB.typelists[type][key]
+		else
+			GLOB.typelists[type][key] = values.Copy()
+	else
+		GLOB.typelists[type] = list()
+		GLOB.typelists[type][key] = values.Copy()
+	return GLOB.typelists[type][key]
+
+GLOBAL_LIST_EMPTY(typelistkeys)
+
+/proc/tallytypelistsavings()
+	var/savings = list()
+	var/saveditems = list()
+	for (var/key in GLOB.typelistkeys)
+		savings[key] = 0
+		saveditems[key] = 0
+
+	for (var/type in GLOB.typelists)
+		for (var/saving in savings)
+			if (GLOB.typelists[type]["[saving]-saved"])
+				savings[saving] += GLOB.typelists[type]["[saving]-saved"]
+				saveditems[saving] += (GLOB.typelists[type]["[saving]-saved"] * length(GLOB.typelists[type][saving]))
+
+	for (var/saving in savings)
+		to_chat(world, "Savings for [saving]: [savings[saving]] lists, [saveditems[saving]] items")
+#endif