hx data

@hx/data

Proxy-based reactive data management for TypeScript. Zero dependencies, tree-shakeable, full type safety.

Core Features

• Nested reactivity — objects and arrays are automatically wrapped in proxies
• Path-based change tracking — subscribe to changes at any depth with dot-notation paths
• Wildcard listening — monitor all changes globally (*) or branch-level (user.*)
• Hierarchy navigation — walk up/down the reactive tree: parent, root, path resolution
• Revocation — unwrap reactive objects back to plain JavaScript
• Typed path utilities — safe deep get/set with full type inference

Installation

pnpm add @hx/data

Quick Example

import { reactive, ERO } from '@hx/data';

// Create a reactive root
const state = reactive({
  user: {
    name: 'John',
    address: { city: 'New York' }
  },
  count: 0
});

// Watch changes
ERO.on(state, 'user.name', (event) => {
  console.log(`Name: ${event.oldValue} → ${event.newValue}`);
});

ERO.on(state, '*', (event) => {
  console.log(`[${event.pathToRoot}] changed`);
});

// Modifications trigger listeners automatically
state.user.name = 'Jane';
state.count = 1;
state.user.address.city = 'Boston';

API Map

Category	API	Description
Creation	reactive()	Create a reactive root object
Listening	ERO.on()	Subscribe to changes
	ERO.off()	Unsubscribe
	ERO.emit()	Manually trigger change event
Inspection	ERO.isReactiveRoot()	Check if object is a reactive root
	ERO.isReactiveObject()	Check if object is reactive
Navigation	ERO.rootOf()	Get root from any nested object
	ERO.parentOf()	Get parent
	ERO.pathOf()	Resolve path to/from any node
	ERO.pathToRoot()	Get absolute path from root
	ERO.pathToParent()	Get path segment from parent
Value access	ERO.getValue()	Get value at path (plain or reactive)
	ERO.setValue()	Set value at path (triggers events)
	ERO.setValueSilent()	Set value without events
Revocation	ERO.revoke()	Unwrap reactive → plain object
Utilities	ERO.fake()	Create a stub reactive object
	get() / set()	Low-level path traversal
	parsePath()	Parse "a.b.[0].c" into segments
	EventEmitter	Standalone pub/sub