As of Babel v7, all the stage presets have been deprecated.Check the blog post for more information.

For upgrade instructions, see the README.

The gist of Stage 1 is:

Stage 1: proposal

What is it? A formal proposal for the feature.

What’s required? A so-called champion must be identified who is responsible for the proposal. Either the champion or a co-champion must be a member of TC39 (source). The problem solved by the proposal must be described in prose. The solution must be described via examples, an API and a discussion of semantics and algorithms. Lastly, potential obstacles for the proposal must be identified, such as interactions with other features and implementation challenges. Implementation-wise, polyfills and demos are needed.

What’s next? By accepting a proposal for stage 1, TC39 declares its willingness to examine, discuss and contribute to the proposal. Going forward, major changes to the proposal are expected

Install

  1. npm install --save-dev @babel/preset-stage-1

Usage

.babelrc

  1. {
  2. "presets": ["@babel/preset-stage-1"]
  3. }

Via CLI

  1. babel script.js --presets @babel/preset-stage-1

Via Node API

  1. require("@babel/core").transform("code", {
  2. presets: ["@babel/preset-stage-1"]
  3. });

Options

loose

boolean, defaults to false.

Enable "loose" transformations for any plugins in this preset that allow them.

useBuiltIns

boolean, defaults to false.

Will use the native built-in instead of trying to polyfill behavior for any plugins that require one.

decoratorsLegacy

boolean, defaults to false.

Use the legacy (stage 1) decorators syntax and behavior.

References