Represents a single subscription to a Signal. Created by Signal:connect
or Signal:once. Can be disconnected to stop receiving future events.
@eryx/signal Module
JSON
A lightweight, re-entrant-safe signal/event system using a doubly-linked list of connections. Signals allow you to fire events and notify all connected callbacks.
Handlers are invoked via task.spawn, so each callback runs in its own
coroutine. Disconnecting or connecting handlers during a Fire is safe -
the handler list is snapshotted before invocation.
local Signal = require("@eryx/signal")
local onDamage = Signal.new()
local conn = onDamage:connect(function(amount)
print("Took " .. amount .. " damage!")
end)
onDamage:fire(25) --> "Took 25 damage!"
conn:disconnect()
onDamage:fire(10) --> (nothing, handler was disconnected)
Summary
Classes
connected: boolean
Signal:connectError<T...>(callback: ((err: any, connection: Connection<T...>) → ())) → Connection<any, Connection<T...>>
API Reference
Classes
Connection
Properties
connected: boolean
Connection._fn
Connection._fn() → ()
Connection:disconnect
Disconnects this connection from its signal. Future fires will no longer invoke this connection's callback. Safe to call multiple times - subsequent calls are a no-op.
Connection:disconnect<T...>() → ()
Signal
A generic event dispatcher. Supports connecting multiple handlers, one-shot handlers, yielding until the next fire, and bulk disconnection.
Properties
Signal.new
Creates a new Signal.
Returns
A new signal with no connections. luau local onPlayerJoin = Signal.new()
Signal:fire
Fires the signal, invoking all connected callbacks with the given arguments.
Each handler runs in its own coroutine via task.spawn. The handler list
is snapshotted before invocation, so connects/disconnects during callbacks
are safe.
Signal:fire<T...>(...) → boolean
Parameters
...
Arguments to pass to each connected handler.
Returns
boolean
true if at least one handler was invoked, false otherwise. luau local sig = Signal.new() sig:connect(function(msg) print(msg) end) sig:fire("hello") --> "hello", returns true
Signal:wait
Yields the current coroutine until the signal is next fired, then returns the fired arguments.
Signal:wait<T...>() → T...
Returns
T...
The arguments passed to the next Fire call. luau -- In a coroutine: local damage = onDamage:wait() print("Waited and received:", damage)
Signal:disconnectAll
Disconnects all connections from this signal. All existing Connection
objects will have their connected property set to false.
Signal:disconnectAll<T...>() → ()
Signal:errorSignal
Returns a lazily-created signal that fires when any handler connected to
this signal raises an error. The error signal fires with (err, connection).
If no error handlers are connected, handler errors are re-thrown so they remain visible rather than being silently swallowed.
local sig = Signal.new()
sig:errorSignal():connect(function(err)
warn("signal handler failed:", err)
end)
Signal:connectError
Connects a callback that will be invoked whenever one of this signal's handlers raises an error. The callback receives the thrown value and the connection whose handler failed.
Signal:connectError<T...>(callback: ((err: any, connection: Connection<T...>) → ())) → Connection<any, Connection<T...>>
Signal:connect
Connects a callback to this signal. The callback will be invoked each time the signal is fired, until the returned Connection is disconnected.
Parameters
callback: ((T...) → ())
The function to call when the signal fires.
Returns
A connection that can be used to disconnect later. luau local conn = signal:connect(function(value) print("Got:", value) end) -- Later: conn:disconnect()
Signal:once
Connects a callback that will only fire once. The connection automatically disconnects itself before invoking the callback.
Parameters
callback: ((T...) → ())
The function to call on the next fire.
Returns
A connection that can be manually disconnected before it fires. luau signal:once(function(value) print("Fired once with:", value) end)