Svelte action for lazy loading Prism.js code highlighting languages from remote or local path.
The action uses IntersectionObserver to dynamically render code highlighting. The prism.js language file is lazy loaded when the <code> element gets visible in the viewport.
$ npm install svelte-prism-action
Include a Prism.js CSS theme in your svelte component or use the <head> section of your index.html.
<link
href="https://unpkg.com/[email protected]/themes/prism.css"
rel="stylesheet"
/>Import prism from svelte-prism-action. Add the action to a component with use:prism. All <code> elements with a class="language-..." will get highlighted once they have entered the viewport.
For available language tags see https://prismjs.com/#supported-languages .
HINT If you are writing your codeblocks directly into a svelte component you need to escape special characters (eg. curley brackets). Another way is to wrap the code inside {``}.
<script>
import { prism } from "svelte-prism-action";
</script>
<!-- add action to component -->
<main use:prism>
<!-- or set some options
<main use:prism={{
componentsUrl: "https://myPathToPrism/components"
}}>
-->
<!-- use in code blocks -->
<pre>
<code class="lang-css">{` <!-- wrap inside {``} if using inside svelte component-->
.bg-gold{
background: gold;
}
`}
</code>
</pre>
<!-- use inline -->
<code class="lang-javascript"
>{`import {prism} from "svelte-prism-action";`}</code
>
</main>You can use componentsUrl to set the URL from where to import the Prism.js language files. By default it uses unpkg cdn, but you can use a local resource instead.
To lazy load third party language files (eg. prism-svelte) or define a different file per language you can use thirdPartyUrls object with language id as key and the URL as the value.
You can also change the IntersectionObserver options. For more information on what they do see https://developer.mozilla.org/en-US/docs/Web/API/Intersection_Observer_API#Interfaces .
<main use:prism={{
root: null,
rootMargin: "100px",
threshold: 0,
componentsUrl: "https://unpkg.com/[email protected]/components",
thirdPartyUrls: {
svelte: "https://cdn.jsdelivr.net/npm/[email protected]/index.js"
}
}}>
...
</main>- Add: Typescript support (generated types from JSDoc)
- make svelte a peer dependency and version less restrictive (because should work with svelte version >= 3)
- Fix: highlight fails when
prism-markup.jsimport not finished
- Fix: SvelteKit error while loading prism-markup.js
- Add: support for third party language files
- Updated dependencies
- Fix #1: SvelteKit support. Fixed vite compile errors and added
/* @vite-ignore */to dynamicimport().
- Updated dependencies
- Add: use custom build
components.jsto reduce package file size - updated dev dependencies
- replaced custom language loader with prism.js builtin loader
- Fix: error if language dependency has dependency on its own
- Fix: error if markdown additional languages is null
- Add: import languages from markdown code blocks
- Fix: loading languages with dependencies (eg. markdown) leads to error
- added .npmignore
- initial release
MIT