Global Event

Due to Vue 3's removal of the Event Bus API, we now implement this functionality using the Mitt package.

Design Philosophy

Global events have the following key characteristics:

1. Volatility: Used for "volatile data" where state persistence isn't necessary
2. Fire and Forget: Events operate on a "Fire & Forget" principle—the outcome of the event trigger isn't monitored
3. Broadcasting: Employs a broadcasting mechanism where all event listeners receive the message, making it inherently shareable
4. Teleportation: Functions similarly to Vue's Provide / Inject or React's Context for cross-level component communication. Unlike these systems, which are confined to UI component lifecycles, global events can operate without such limitations. This allows data transport from state machines to Pinia, even though state machines operate independently of Vue's state management system.

Scope of Responsibilities

Global events and Pinia's global state functionality share many similarities, with volatility being the key distinction—specifically, whether state persistence is possible.

Global events are transient: once used, they don't maintain state. While receivers can process the incoming data, any storage will remain local state, not shareable across components.

Global state, on the other hand, maintains a shared state across the application, making it ideal for data that needs to be stored and accessed by multiple components.