vue-mvvm

Appearance

Syncio ​

Syncio is a utility module for handling potentially asynchronous operations in a uniform way.

Overview ​

In the framework, many methods (like lifecycle hooks or actions) can return either a plain value (synchronously) or a Promise (asynchronously). Syncio provides a single entry point to ensure these are handled correctly without duplicating if (val instanceof Promise) logic everywhere.

API Reference ​

ensureSync<T>(val: T | Promise<T>): Promise<Awaited<T>> ​

Ensures that a value is awaited if it is a Promise.

  • val: The value or promise to be awaited.
  • Returns: A Promise that resolves to the actual value of type T.

Why Syncio? ​

Vue doesn't always await its lifecycle hooks, but sometimes the framework or user needs to ensure certain cleanup or coordination happens.

Syncio is used internally for:

  • Action Execution: Awaiting onAction results in ViewModel.runAction.
  • Delegates: Awaiting each subscriber during a SEQUENTIAL invoke or all subscribers during a PARALLEL invoke.
  • Router Guards: Awaiting RouteAdapter.guard results.
  • Lifecycle Management: Awaiting unmounted hooks in useViewModelInstance.

By using ensureSync, the framework can support both synchronous and asynchronous user code with minimal overhead.

typescript
import {syncio} from 'vue-mvvm';

async function process(something: string | Promise<string>) {
    // We don't care if it's a promise or a string, we just want the value.
    const val = await syncio.ensureSync(something);
    console.log(val);
}