Exclude other types from type in luau type check

[Bam_Sori]

I have written a custom instance module.

If I pass (workspace.aNpc) to the constructor function of this module,
it returns a custom instance.
This instance matches the type of workspace.aNpc , enhanced with some custom properties, methods, and events.

e.g.

function module.new<object>(object:object):
	{isDead:bool, toBinaryCode:()->str, died:goodSignal} & object

	local self = setmetatable({},customInstance)
	--some codes
	return self
end

However, I wish to exclude certain events or features from the original Instance.

{ChildAdded:nil} & object

Despite setting the undesired event to nil to exclude it, it still appears due to automatic completion.

[IAmBanFor_Devforum (DevforumAccount)]

You can’t hide events or features of the original Instance. Only the Roblox API(Which you can’t modify to your liking) can do that. But you can replace it some how.

[MagmaBurnsV]

There’s an RFC for Shape Types which I believe is what you’re trying to achieve. Currently, the types for host-specified userdata are immutable so you can’t do this.

Nevertheless, what you’re trying to achieve isn’t going to scale well. You’d probably be better off just storing the object as a property of the class and then short-circuiting your properties/events through it.

self.Object = Object
self.ChildAdded = Object.ChildAdded