hook

GMod-style event system. Register named callbacks for engine events; the name lets you replace or remove your own hook later.

functionhook.Add(event, name, fn)

Registers fn for event under a unique name. Adding again with the same event + name replaces the previous callback.

Param	Type	Notes
event	string	Event name, e.g. `"OverlayElement"`.
name	string	Unique identifier for this callback.
fn	function	Called with the event's arguments.

functionhook.Remove(event, name) → nil

Unregisters the callback previously added under this event + name.

Param	Type	Notes
event	string	The event name.
name	string	The unique identifier used in `hook.Add`.

functionhook.Run(event, ...) → nil · alias: hook.Call

Fires an event, calling every registered callback with the given arguments. The engine uses this to dispatch events, but you can also define and fire your own custom events between mods.

Param	Type	Notes
event	string	The event name to fire.
...	any	Any number of arguments, passed through to each callback.

functionhook.RunReturn(event, ...) → any | nil

Like Run, but stops at the first callback that returns a non-nil value and hands that value back. This is how a handler consumes an event instead of merely observing it — OnFrameReceived is dispatched with it, so a mod that has fully handled a frame can say so and the rest are not called. Callback order between mods is not defined, so do not build anything that depends on getting there first. Errors are caught and logged per callback, exactly as with Run.

Param	Type	Notes
event	string	The event name to fire.
...	any	Any number of arguments, passed through to each callback.

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