StateMachine

This is a state machine module I made cause I'm sick of writing janky if-chains to manage character states, and you should be too If you aren't then this ain't for you

Handles transitions, async exits, validation, and gives you a nice little Signal API to hook into changes

Creating a new StateMachine

local Machine = StateMachine.New()

Adding states

Machine:AddState("Idle", {
	OnStart = function(self, old) print("Entered Idle from", old) end,
	OnEnd = function(self, new) print("Leaving Idle to", new) end,
	Transitions = {
		Run = true
	}
})

Changing states

Machine:SetState("Run")
-- will run OnEnd of current state, then OnStart of the new one
-- won't switch if transition is invalid or blocked

Wanna override the rules and switch anyway?

Machine:ForceState("Climb")
-- however, this will NOT fire .OnStateChanged and any other events or functions
-- wanna force a state AND have the events? do :SetState(state,true)

Going back

Machine:GoBack() -- switches to the previous state
-- i dont recommend using it

Events you can listen to

Machine.OnStateChanged:Connect(function(from, to)
	print("Switched from", from, "to", to)
end)

Machine.OnStateAdded:Connect(function(name, config)
	print("Added state:", name)
end)

Machine.OnStateRemoved:Connect(function(name)
	print("Removed state:", name)
end)

Other useful stuff

Machine:GetState() --> CurrentState, LastChangedTime
Machine:IsState("Idle", "Run", ...) -- true if current state is one of those
Machine:CanChangeTo("Idle", "Jump") -- returns true/false based on transition rules. You can do :CanChangeTo("Jump") and it uses the current state
Machine:SetTransition("Idle", "Run", true) -- manually allow or block transitions
Machine:RemoveState("Die") -- remove a state, duh
Machine:Destroy() -- bye bye state machine

Notes

• Async exit logic can be handled with EndAsync, which returns true/false to allow or deny the new state
• Has debug protection against writing to the state table directly. Don't do that