Build JavaScript

Builds the app/js/index.js file into app/static/js/app.min.js. The code is transformed and bundled using Babel and webpack, so the latest JavaScript features can be used (including ECMAScript 2015 aka ES6 and newer standards). Requires Node.js to be available on the system.

Usage

build_js(watch = FALSE)

Arguments

watch

Keep the process running and rebuilding JS whenever source files change.

Value

None. This function is called for side effects.

Details

Functions/objects defined in the global scope do not automatically become window properties, so the following JS code:

function sayHello() { alert('Hello!'); }

won't work as expected if used in R like this:

tags$button("Hello!", onclick = 'sayHello()');

Instead you should explicitly export functions:

export function sayHello() { alert('Hello!'); }

and access them via the global App object:

tags$button("Hello!", onclick = "App.sayHello()")

Examples

if (interactive()) {
  # Build the `app/js/index.js` file into `app/static/js/app.min.js`.
  build_js()
}