Signal

type Signal<T...> = {
    RBXScriptConnection: RBXScriptConnection?,

    Connect: <U...>(self: Signal<T...>, fn: (...unknown) -> (), U...) -> Connection<U...>,
    Once: <U...>(self: Signal<T...>, fn: (...unknown) -> (), U...) -> Connection<U...>,
    Wait: (self: Signal<T...>) -> T...,
    Fire: (self: Signal<T...>, T...) -> (),
    DisconnectAll: (self: Signal<T...>) -> (),
    Destroy: (self: Signal<T...>) -> (),
}

Constructors

new

Returns a new signal instance which can be used to connect functions.

local LemonSignal = require(path.to.LemonSignal)

local signal = LemonSignal.new()

wrap

Returns a new signal instance which fires along with the passed RBXScriptSignal.

Players.PlayerAdded:Connect(function(player)
print(player, "joined, from RBXScriptSignal")
end)

local playerAdded = LemonSignal.wrap(Players.PlayerAdded)
local connection = playerAdded:Connect(function(player)
print(player, "joined, from LemonSignal")
end)

playerAdded:Wait()
-- Player1 joins after some time passes

--> Player1 joined, from RBXScriptSignal
--> Player1 joined, from LemonSignal

connection:Disconnect()
playerAdded:Wait()
-- Player2 joins after some time passes

--> Player2 joined, from RBXScriptSignal

connection:Reconnect() -- Now we get our hands on more API!
-- Player3 joins after some time passes

--> Player3 joined, from RBXScriptSignal
--> Player3 joined, from LemonSignal

-- It can also be used to mock Roblox event fires.
playerAdded:Fire(playerAdded, Players:FindFirstChildOfClass("Player")) --> Player1 joined, from LemonSignal

Properties

RBXScriptConnection

The RBXScriptConnection that gets made when using .wrap. It gets disconnected and removed when using :Destroy.

local bindable = Instance.new("BindableEvent")

local signal = LemonSignal.wrap(bindable.Event)

local scriptConnection = signal.RBXScriptConnection

print(signal.RBXScriptConnection) --> Connection

signal:Destroy()

print(scriptConnection.Connected) --> false
print(signal.RBXScriptConnection) --> nil

Methods

Connect

Connects a function to the signal and returns the connection. Passed variadic arguments will always be prepended to fired arguments.

local signal = LemonSignal.new()

local connection1 = signal:Connect(function(str: string)
print(str)
end)

local connection2 = signal:Connect(print, "Hello")

signal:Fire("world!")
--> Hello world!
--> world!

Once

Connects a function to a signal and returns a connection which disconnects on the first fire. Can be reconnected later.

local signal = Signal.new()

local connection = signal:Once(print, "Test:")

signal:Fire("Hello world!") --> Test: Hello world!

print(connection.Connected) --> false

Wait

Yields the coroutine until the signal is fired and returns the fired arguments.

local signal = LemonSignal.new()

task.delay(1, function()
    signal:Fire("Hello", "world!")
end)

local str1, str2 = signal:Wait()
print(str1) --> Hello
print(str2) --> world!

Fire

Fires the signal and calls all connected functions with the connection's bound arguments and the fired arguments.

local signal = LemonSignal.new()

local connection = signal:Connect(print, "Test:")

signal:Fire("Hello world!") --> Test: Hello world!

DisconnectAll

Disconnects all connections currently connected to the signal. They may be reconnected later.

local signal = LemonSignal.new()

local connection1 = signal:Connect(print, "First:")
local connection2 = signal:Connect(print, "Second:")

signal:Fire("Hello world!")
--> Second: Hello world!
--> First: Hello world!

signal:DisconnectAll()

signal:Fire("Goodbye World!")

Destroy

Similar to DisconnectAll but also disconnects the RBXScriptConnection made using .warp. Contrary to the method's name, the signal remains usable.

local signal = LemonSignal.new()

local connection = signal:Connect(print, "Hello")

signal:Fire("world!")
--> Hello world!

signal:Destroy()

signal:Fire("Goodbye World!")