babel-register
One of the ways you can use Babel is through the require hook. The require hook
will bind itself to node's require
and automatically compile files on the
fly. This is equivalent to CoffeeScript's
coffee-script/register.
Install
npm install babel-register --save-dev
Usage
require("babel-register");
All subsequent files required by node with the extensions .es6
, .es
, .jsx
and .js
will be transformed by Babel.
Polyfill not included
You must include a polyfill separately when using features that require it, like generators.
node_modules
by default
Ignores NOTE: By default all requires to node_modules
will be ignored. You can
override this by passing an ignore regex via:
require("babel-register")({
// This will override `node_modules` ignoring - you can alternatively pass
// an array of strings to be explicitly matched or a regex / glob
ignore: false
});
Specifying options
require("babel-register")({
// Optional ignore regex - if any filenames **do** match this regex then they
// aren't compiled.
ignore: /regex/,
// Ignore can also be specified as a function.
ignore: function(filename) {
if (filename === "/path/to/es6-file.js") {
return false;
} else {
return true;
}
},
// Optional only regex - if any filenames **don't** match this regex then they
// aren't compiled
only: /my_es6_folder/,
// Setting this will remove the currently hooked extensions of .es6, `.es`, `.jsx`
// and .js so you'll have to add them back if you want them to be used again.
extensions: [".es6", ".es", ".jsx", ".js"],
// Setting this to false will disable the cache.
cache: true
});
You can pass in all other options as well,
including plugins
and presets
. But note that the closest .babelrc
to each file still applies, and takes precedence over any options you pass in here.
Environment variables
By default babel-node
and babel-register
will save to a json cache in your
temporary directory.
This will heavily improve with the startup and compilation of your files. There are however scenarios where you want to change this behaviour and there are environment variables exposed to allow you to do this.
BABEL_CACHE_PATH
Specify a different cache location.
BABEL_CACHE_PATH=/foo/my-cache.json babel-node script.js
BABEL_DISABLE_CACHE
Disable the cache.
BABEL_DISABLE_CACHE=1 babel-node script.js