Synapsev5.0.6

State Manager

Creating Storages

Working with Data

Patterns

Recipes

Business Logic Layer

createSynapse

React

Utilities

Recipes

API

API Client

API Hooks (React)

Network / fetch

Working example on GitHubDeleteHasKeysExample.tsx

remove / has / keys / clear / reset

Operations for checking existence, removing keys, and resetting the storage. The examples use the end-to-end todoStorage (TodoState = { todos: Todo[]; filter: Filter }). They work the same way for all storage types — for IndexedDB the same methods return a Promise.

has(key) — Check whether a key exists

typescript
// ── Synchronous storage (MemoryStorage / LocalStorage) ──

todoStorage.has('todos')     // true
todoStorage.has('filter')    // true
todoStorage.has('unknown')   // false

// ── Asynchronous storage (IndexedDBStorage) ──

await todoStorage.has('todos')     // true
await todoStorage.has('unknown')   // false

keys() — Get all keys

typescript
// ── Synchronously ──
const allKeys = todoStorage.keys()
// ['todos', 'filter']

// ── Asynchronously ──
const allKeys = await todoStorage.keys()

remove(key) — Remove a specific key

typescript
// Removes a key from the storage.
// After removal has(key) returns false, and keys() does not contain that key.

// ── Synchronously ──
todoStorage.remove('filter')
todoStorage.has('filter')   // false
todoStorage.keys()          // ['todos']

// ── Asynchronously ──
await todoStorage.remove('filter')

clear() — Clear the storage

typescript
// Removes ALL keys. The state becomes an empty object {}.

// ── Synchronously ──
todoStorage.clear()
todoStorage.getState()   // {}
todoStorage.keys()       // []

// ── Asynchronously ──
await todoStorage.clear()

reset() — Reset to initialState

typescript
// Returns the state to its initial value (initialState from the config).

// ── Synchronously ──
todoStorage.reset()
todoStorage.getState()   // { todos: [...], filter: 'all' }

// ── Asynchronously ──
await todoStorage.reset()

clear() vs reset() — What's the difference

typescript
const todoStorage = new MemoryStorage<TodoState>({
  name: 'todo',
  initialState: { todos: [], filter: 'all' },
})

todoStorage.set('filter', 'completed')

// clear() — a full wipe
todoStorage.clear()
todoStorage.getState()   // {}
todoStorage.keys()       // []

// reset() — back to initialState
todoStorage.reset()
todoStorage.getState()   // { todos: [], filter: 'all' }
todoStorage.keys()       // ['todos', 'filter']