This is an internal package used by vue-loader and vueify. It processes the raw render functions generated by vue-template-compiler to:

1. add support to ES2015 features in template expressions via Buble. (see supported features here).

Note: since version 1.8.0, object rest spread usage inside templates are transpiled to Object.assign calls by default. This means if you need to support IE, you will need to polyfill Object.assign. (Latest version of Vue CLI will do this for you).

2. remove the with block inside render functions to make it strict-mode compliant. This is performed only at build time so that the base template compiler can be extremely small and lightweight.

The buble implementation is built from a fork at https://github.com/yyx990803/buble