Signal

Signal is a module for replicating the behavior of a BindableEvent, and likewise, RBXScriptConnection/Signal, but without the same performance implications.

This module uses the same logic as GoodSignal, which blends performance with usability.

It is implemented in pure Luau.

Types

Signal

The object returned by Signal.new()

export type Signal<T...> = {
	_head: Listener<T...>?,

	Connect: (Signal<T...>, Callback: Callback<T...>) -> Connection<T...>,
	Once: (Signal<T...>, Callback: Callback<T...>) -> Connection<T...>,
	Fire: (Signal<T...>, T...) -> (),
	Wait: (Signal<T...>) -> T...,
}

Connection

The object returned by Connect, and by proxy, Once

export type Connection<T...> = {
	_signal: Signal<T...>,
	_listener: Listener<T...>,

	Connected: boolean,
	Disconnect: (Connection<T...>) -> (),
}

Constructors

new

The primary constructor for creating a Signal object

local Signal = require(...)

local signal = Signal.new()

Methods

Fire

Tells your signal to invoke all the functions associated with it via Connect.

This method can be called inside of an event handler.

This method never allocates memory, unless you yield in the event handler.

local Signal = require(...)

local signal = Signal.new()

signal:Connect(function(argument)
    print(`Callback invoked with argument of '{argument}'`)
end)

signal:Fire("Firing a signal!") --> "Callback invoked with argument of 'Firing a signal!'"

Connect

Associates a callback to your signal, also known as an event handler.

This method returns a Connection object, with a Connected boolean, and a Disconnect method.

You can use this method within another event handler.

local Signal = require(...)

local signal = Signal.new()

local connection = signal:Connect(function(argument)
    print("Callback was invoked")
end)

print(connection.Connected) --> true
signal:Fire() --> "Callback was invoked"

connection:Disconnect()

print(connection.Connected) --> false
signal:Fire() --> nothing

Once

Identical to Connect, but disconnects its own connection immediately after the first invocation.

This method internally uses Connect.

local Signal = require(...)

local signal = Signal.new()

local connection = signal:Once(function()
    print("This will only print once")
end)

print(connection.Connected) --> true
signal:Fire() --> "This will only print once"
print(connection.Connected) --> false
signal:Fire() --> nothing

Wait

Pauses the current thread until your signal receives an invocation.

This method internally uses Once.

local Signal = require(...)

local signal = Signal.new()

local startTime = os.clock()
task.delay(3, function()
    signal:Fire()
end)

signal:Wait()
print(os.clock() - startTime) --> Greater than 3 seconds