nuxt-composables

Nuxt Composables

Creating reusable stateful logic via Vue Composition API.

Core Concepts

composables.md - Patterns, naming, state management, best practices

multi-step-state.md - SSR-safe shared state across routes via useState, deriving step from route.path, submit-with-side-effects, why caller owns loading

Singleton Pattern (Shared State)

State defined outside function persists across all callers:

// app/composables/useUser.ts
let user = ref<User>()  // Singleton - shared across app

export default function useUser() { const setUser = (data: BaseEntity) => { user.value = User.hydrate(data) } const clearUser = () => { user.value = undefined }

return { user, setUser, clearUser } }

## Factory Pattern (Fresh State)

State defined inside function - new instance per call:

```typescript
// app/composables/useCounter.ts
export default function useCounter(initial = 0) {
  const count = ref(initial)  // Fresh per call
  const increment = () => count.value++
  const decrement = () => count.value--

  return { count, increment, decrement }
}

Naming & File Conventions

Convention	Example
File name	useUser.ts, useCategories.ts
Function	export default function useUser()
Return	Always object { state, methods }
Refs	Reactive: user, not userRef