[Closed] Persistent when construct

something like this:

global WhenSelectMonitor 
(
	struct WhenSelectMonitorStruct
	(
		eventCallback,  

		WhenSelect = 
		(
			attributes WhenSelect attribID:#(1234567, 7654321)
			(
				fn getNode = if (owner = custattributes.getowner this) != undefined do refs.dependentnodes owner firstonly:on
				fn onOwnerSelected node: = 
				(
					if node == unsupplied do node = getNode()
					if isvalidnode node do
					(
						format "node:% selected:%
" node node.isselected
					)
				)
				parameters params 
				(
				)
				rollout params "When Select" 
				(
				)
			)
		),
		fn hasWhenSelect node = isvalidnode node and
		(
			custattributes.get node.baseobject this.WhenSelect != undefined
		),
		fn onSelectionChanged event handles = 
		(
			for handle in handles do
			(
				node = getAnimByHandle handle
				if ::WhenSelectMonitor.hasWhenSelect node do
				(
					node.WhenSelect.onOwnerSelected node:node
				)
			)
		),
		on create do
		(
			eventCallback = NodeEventCallback selectionChanged:onSelectionChanged
		)
	)
	WhenSelectMonitor = WhenSelectMonitorStruct()
)


delete objects
b = box()
attr = createinstance WhenSelectMonitor.WhenSelect
append b.baseobject.custattributes attr

When do you choose to use the node event system vs. general event #selectionSetChanged callback? Is one more efficient than the other?

Makes sense.