babel-preset-mjs

Babel preset to transpile JS to restricted mjs JS.

Features

| Restriction | Solution | | ----------- | -------- | | No String, Number, RegExp, Date, Function, etc. | Not solved | | No try/catch/finally. | Transpiled to functions that make try/catch/finally work. | | No error classes. | Not solved | | No new or prototypes. In order to create an object with a custom prototype, use Object.create(), which is available. | new is handled by Object.create(), and the constructor is called on the resultant object | | Strict mode only. No for..of, =>, destructors, generators, proxies, promises, classes, template strings. | Handled by babel-preset-es2015 (included by default). | | No var, only let. | All uses of var are changed to let. | | No getters, setters, valueOf. | Not solved | | No == or !=, only === and !==. | All uses of == are transpiled to a manually evaluated loose equals. | | load() is used to load external JS, not very standardized and pollutes the global scope. | Not solved | | No setTimeout() and setInterval() API. | Polyfilled using api_timer.js. |

Usage

.babelrc:

{
  "presets": [
    "mjs"
  ]
}

License

Licensed under MIT license.

Copyright (C) 2017 Karim Alibhai.