@motioneffector/flags

A TypeScript library for managing application state with powerful condition evaluation and reactive subscriptions.

Features

• Multiple Value Types - Boolean flags, numeric counters, and string values
• Powerful Conditions - Complex expressions with AND, OR, NOT, comparisons
• Reactive Subscriptions - Watch all changes or specific keys
• Persistent Storage - Save/load to localStorage or custom backends
• Undo/Redo History - Built-in time-travel debugging support
• Computed Values - Derived flags that auto-update on dependency changes
• Namespacing - Organize flags into logical scoped groups
• Batch Operations - Atomic updates with automatic rollback

Read the full manual →

Quick Start

import { createFlagStore } from '@motioneffector/flags'

const store = createFlagStore({
  initial: { gold: 0, has_key: false, reputation: 50 }
})

// Simple operations
store.set('has_key', true)
store.increment('gold', 25)

// Powerful condition evaluation
if (store.check('gold >= 20 AND !has_key')) {
  store.decrement('gold', 20)
  store.set('has_key', true)
}

// Subscribe to changes
store.subscribe((key, newValue, oldValue) => {
  console.log(`${key}: ${oldValue} → ${newValue}`)
})

Testing & Validation

• Comprehensive test suite - 569 unit tests covering core functionality
• Fuzz tested - Randomized input testing to catch edge cases
• Strict TypeScript - Full type coverage with no any types
• Zero dependencies - No supply chain risk

License

MIT © motioneffector