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State Management

Reef uses data reactivity to update your UI.

Data reactivity means that the UI “reacts” to changes in your data. Update your data, and the UI automatically renders any required updates based on the new state.

// Create a component and render it
var app = new Reef('#app', {
	data: {
		greeting: 'Hello',
		name: 'world'
	template: function (props) {
		return `<h1>${props.greeting}, ${}!</h1>`;

// This causes component to update with "Hi, universe" = 'Hi'; = 'Universe';

You can also update the entire data object.

// This will also update the UI = {
	greeting: 'Hi',
	name: 'Universe'

Try data reactivity on CodePen →

For better performance, multiple property updates may be batched into a single, asynchronous render. You can detect when a render has been completed using the render event hook.

Non-Reactive Data

Sometimes, you want to update data without updating the UI.

You can get an immutable copy of your data by passing it into the Reef.clone() method. This creates a non-reactive copy of your data that won’t affect the state of your component.

// Create an immutable copy of the
var data = Reef.clone(;

// Update the copy
// This does NOT update the or render a new UI = 'Universe';

When you’re ready to update your component data, you can set the component’s data property to your cloned copy.

// Reactively update the component data = data;

Try non-reactive data on CodePen →

Note: You can use the Reef.clone() method to create an immutable copy of any array or object, not just your component data.

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