xm

A tiny compiler for HTML that adds imports, slots/fills and markdown tags.

Usage no npm install needed!

<script type="module">
  import xm from 'https://cdn.skypack.dev/xm';
</script>

README

₪ xm - extensible HTML

xm is a tiny compiler for HTML that adds

  • <import> tag to inline external HTML files
  • <slot> and <fill> tags to define slots and fill them with content
  • <markdown> tag to portal into Markdown

screenshot of an html template with slots

screenshot of an html page that imports the previous example and fills the slots

xm CLI comes with a dev mode that compiles and serves built HTML.

Furthermore xm is built on top of posthtml-cli and therefore it is extensible.

Are you using xm? Share your site's URL here.

Install

npm i -g xm

Usage

Usage: xm <command> [options]

Commands:

  dev     Compiles HTML files on change and serves the root folder
  build   Compiles the HTML files once
  help    Displays help

Options:

  --root       Folder to compile (default ./)
  --output     Output (destination) folder. This is necessary only when using xm build
  --htmlOnly   Compile and copy only the built HTML files

<import> element

Allows to inline (import) HTML files into the current one.

<import src="file.html" />

Paths are relative.

<!-- src/folder/index.html -->

<import src="file.html" />
<!-- file.html -> src/folder/file.html -->

You can prefix paths with / to make them absolute i.e. relative to the --root value.

$ xm build --root ./src
# <import src="file.html" />
# -> ./src/file.html

Importing markdown files

xm supports importing .md (markdown) files too. When importing such files the front matter declarations are converted to fill elements.

<style>
  /* theme */
</style>
<import src="README.md" />

💡 This feature can be used to generate styled docs sites for your open source project!

If you create a reusable theme for README-like files we encourage you to use the following naming convention:

xm-theme-<theme-name>

Share your site or theme URL here.

<slot> and <fill> elements

HTML files can define slot elements with an attribute name. slots can be filled when importing HTML files using the fill tag.

<!-- base.html -->

<!DOCTYPE html>
<title><slot name="title"></slot></title>
<main>
  <slot name="main"></slot>
</main>

<!-- about.html -->

<import src="base.html">
  <fill name="title">About</fill>
  <fill name="main">
    <h1>About</h1>
    <p>welcome</p>
  </fill>
</import>
<footer>Unique to this page</footer>

<!-- about.html (compiled with xm) -->

<!DOCTYPE html>
<title>About</title>
<main>
  <h1>About</h1>
  <p>welcome</p>
</main>
<footer>Unique to this page</footer>

You can also define a special unnamed slot that will be filled with the import children that are not fill tags:

<!-- base.html -->

<slot></slot>
<footer><slot name="footer"></slot></footer>

<!-- about.html -->

<import src="base.html">
  <fill name="footer">good bye</fill>
  hello
  <p>friend</p>
</import>

<!-- about.html (compiled with xm) -->

hello
<p>friend</p>
<footer>good bye</footer>

Credits

  • Ivan Demidov for helping me out with PRs and PostHTML
  • askucher for transferring ownership of the xm package