gitlab-org--gitlab-foss/app/assets/javascripts/render_math.js
2017-11-22 18:51:06 +00:00

51 lines
1.1 KiB
JavaScript

/* global katex */
// Renders math using KaTeX in any element with the
// `js-render-math` class
//
// ### Example Markup
//
// <code class="js-render-math"></div>
//
// Only load once
let katexLoaded = false;
// Loop over all math elements and render math
function renderWithKaTeX(elements) {
elements.each(function katexElementsLoop() {
const mathNode = $('<span></span>');
const $this = $(this);
const display = $this.attr('data-math-style') === 'display';
try {
katex.render($this.text(), mathNode.get(0), { displayMode: display });
mathNode.insertAfter($this);
$this.remove();
} catch (err) {
throw err;
}
});
}
export default function renderMath($els) {
if (!$els.length) return;
if (katexLoaded) {
renderWithKaTeX($els);
} else {
$.get(gon.katex_css_url, () => {
const css = $('<link>', {
rel: 'stylesheet',
type: 'text/css',
href: gon.katex_css_url,
});
css.appendTo('head');
// Load KaTeX js
$.getScript(gon.katex_js_url, () => {
katexLoaded = true;
renderWithKaTeX($els); // Run KaTeX
});
});
}
}