html-string

A templating library based on JavaScript tagged template literals.

• Works on Node and in the browser.
• Written in Typescript.
• It does not require special editor plugins, formatters, compilers, etc as it's used as just standard JavaScript syntax. Optionally installing the VSCode lit-html extension will improve the experience with full intellisense support inside the HTML. Click to go to definition of interpolated values and nested components, autocompletion, eslint and prettier support, syntax coloring, renaming symbols, auto closing tags, emmet, etc
• Client side interactivity can be implemented with Stimulus, Alpine or similar libraries. See the examples directory.

Quick Example:

const html = require("html-string");
// Or alternatively:
// import html from "html-string"

const TodoItem = ({ title, completed }) => html`
  <li>${title} ${completed ? "✅" : "❌"}</li>
`;

const TodoList = ({ todos, completedCount, ...attrs }) => html`
  <ul ${html.attrs(attrs)}> // html.attrs() will convert any extra arguments to html attributes.
    ${todos.map(todo => TodoItem(todo))}
  </ul>
  ${completedCount && html`<p>${completedCount} tasks completed</p>`}
`;

const todos = [
  { title: "Task one", completed: true },
  { title: "Task two", completed: false }
];

const completedCount = todos.filter(todo => todo.completed).length;

const todoList = TodoList({ todos, completedCount, id: "tasks", dataCustom: "value", dataSomeBool: true});
const htmlOutputForTheBrowser = html.render(todoList);
console.log(htmlOutputForTheBrowser);

/*
Output would be:
  <ul id="tasks" data-custom="value" data-some-bool>
    <li>Task one ✅</li>
    <li>Task two ❌</li>
  </ul>
  <p>1 tasks completed</p>
*/

There are examples more examples here

Note By default, all interpolated values are XSS escaped using the xss library. This is for security reasons so that if a malicious value is passed in, let's say: <script>alert('hello')</script> then the tags will be automatically escaped.

When you are 100% sure that the provided value is safe, you can use html.unsafe() helper to make it to not be escaped. For example if in the previous example the value of a TodoItem's title could be some html entered by the user and you trust the entered value or you have already escaped it, then you could rewrite it as:

const TodoItem = ({ title, completed }) => html`
  <li>${html.unsafe(title)} ${completed ? "✅" : "❌"}</li>
`;

The html.unsafe() helper in the previous template would skip the XSS protection.

Available helpers

html.unsafe(value)

Mark the value as safe for raw output (no XSS escaping).

html.attrs(value)

Convert each property of the passed value object to html attributes. Camelcase names are converted to kebab-case. For example {dataCustom: "value"} will be rendered as data-custom="value".

Available modifiers

safe

Mark the preceding interpolated value as safe for raw output (no XSS escaping).

attrs

Convert each property of the preceding interpolated value to html attributes. Camelcase names are converted to kebab-case. For example {dateCustom: "value"} will be rendered as data-custom="value".

Editor support

If you are using Visual Studio Code, you can use the lit-html extension for syntax highlighting, autocompletion, etc.

Inspired by lit-html and JSX.