How to include JS file into rmarkdown file?

[cderv]

You can insert JS code in a R Markdown document using a js engine like in this example

7.12 Use the disclosure element | R Markdown Cookbook

Otherwise, you can use includes to insert code in the HTML templates

3.1 HTML document | R Markdown: The Definitive Guide

But usually, JS library to be used in Shiny apps or HTML R Markdown are packaged as htmlwidgets or HTML dependencies with htmltools. See more at

• https://www.htmlwidgets.org/
• Tools for HTML • htmltools
• JavaScript for the R package developer - R-hub blog
• Chapter 4 Handle HTML dependencies with {htmltools} | Outstanding User Interfaces with Shiny and more in this book.
• This JS for R book https://book.javascript-for-r.com/

You can then package this JS library in a R package to share its usage across document and users for examples