Handlebars

Description #

Handlebars is a popular logic-less templating language that extends Mustache with powerful features like helpers, partials, and block expressions for rendering HTML from dynamic data.

History #

Handlebars was created by Yehuda Katz in 2010 as a superset of Mustache. It was designed to maintain Mustache’s simplicity while enabling more expressive and reusable template features for client and server-side apps.

Hello World Code #

<h1>{{message}}</h1>

With JavaScript:

const source = "<h1>{{message}}</h1>";
const template = Handlebars.compile(source);
const html = template({ message: "Hello, World!" });
document.body.innerHTML = html;

How to Run #

Option 1: Online
Try it in-browser with this demo:
https://tryhandlebarsjs.com/

Option 2: Local
Install via npm:

npm install handlebars

Basic Node.js usage:

const Handlebars = require("handlebars");
const template = Handlebars.compile("<h1>{{message}}</h1>");
console.log(template({ message: "Hello, World!" }));

Key Concepts #

• Uses {{ }} for output and {{# }} for logic blocks
• Helpers for custom functions inside templates
• Partials for reusable fragments
• Context-aware rendering with nested data
• Safe by default with escaping
• Works on client and server
• Popular with Ember.js, Assemble, and Ghost CMS
• Supports control flow like #if, #each, #with
• Can precompile templates for faster rendering
• Active community with rich plugin support

Try It Online #

https://tryhandlebarsjs.com

Fun Facts #

• Handlebars is used in major platforms like Ghost, Slack, and Ember.js.
• Its name comes from the double curly braces {{ }}, resembling handlebars.
• Handlebars templates can be compiled and cached ahead of time for performance.

Resources #

Official site
Docs or tutorial
GitHub or interpreter
Community or learning resources