Types

Pinia

The Pinia instance type (returned by createPinia()).

Member	Signature	Notes
use	(plugin: PiniaPlugin) => Pinia	register a plugin, chainable
install	(app: any) => void	app.use(pinia) entry (reliable on Web only; use setActivePinia on native)

PiniaPlugin

export type PiniaPlugin = (ctx: PiniaPluginContext) => void

Plugin function type. UTS constraint: returns void (no object merging into the store); hook logic goes through the context.

PiniaPluginContext

export type PiniaPluginContext = {
  pinia: Pinia,
  store: any,
  storeId: string
}

Field	Notes
pinia	the current Pinia instance
store	the newly created store instance (any; narrow with as at the use site)
storeId	the store id

Unsubscribe

export type Unsubscribe = () => void

Unsubscribe handle (the return shape of per-field watch).

Store type convention

Store types are user-defined type aliases with explicit annotations (object literals can only be assigned to type aliases):

export type CounterStore = {
  count: Ref<number>,                 // state: Ref<T>
  doubleCount: ComputedRef<number>,   // getter: ComputedRef<T>
  increment: () => void               // action: arrow function
}

WARNING

ComputedRef must be imported explicitly: import type { ComputedRef } from 'vue' (not globally injected). Ref is injected, but importing both explicitly is recommended.