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diff --git a/node_modules/babel-plugin-transform-es2015-modules-commonjs/README.md b/node_modules/babel-plugin-transform-es2015-modules-commonjs/README.md new file mode 100644 index 0000000..c553eee --- /dev/null +++ b/node_modules/babel-plugin-transform-es2015-modules-commonjs/README.md @@ -0,0 +1,142 @@ +# babel-plugin-transform-es2015-modules-commonjs + +> This plugin transforms ES2015 modules to [CommonJS](http://wiki.commonjs.org/wiki/Modules/1.1). +> +> #### Babel 6 Changes +> +> Babel 6 changed some behavior by not doing `module.exports = exports['default']` anymore in the modules transforms. +> +> There are some caveats, but you can use [babel-plugin-add-module-exports](https://www.npmjs.com/package/babel-plugin-add-module-exports), so that updating to Babel 6 isn't a breaking change since users that don't use ES modules don't have to do `require("your-module").default`. +> +> However, it may not match how Node eventually implements ES modules natively given the [the current proposal](https://github.com/nodejs/node-eps/blob/master/002-es-modules.md#46-es-consuming-commonjs). + +## Example + +**In** + +```javascript +export default 42; +``` + +**Out** + +```javascript +Object.defineProperty(exports, "__esModule", { + value: true +}); + +exports.default = 42; +``` + +## Installation + +```sh +npm install --save-dev babel-plugin-transform-es2015-modules-commonjs +``` + +## Usage + +### Via `.babelrc` (Recommended) + +**.babelrc** + +```js +// without options +{ + "plugins": ["transform-es2015-modules-commonjs"] +} + +// with options +{ + "plugins": [ + ["transform-es2015-modules-commonjs", { + "allowTopLevelThis": true + }] + ] +} +``` + +### Via CLI + +```sh +babel --plugins transform-es2015-modules-commonjs script.js +``` + +### Via Node API + +```javascript +require("babel-core").transform("code", { + plugins: ["transform-es2015-modules-commonjs"] +}); +``` + +## Options + +### `loose` + +`boolean`, defaults to `false`. + +As per the spec, `import` and `export` are only allowed to be used at the top +level. When in loose mode these are allowed to be used anywhere. + +And by default, when using exports with babel a non-enumerable `__esModule` property +is exported. + +```javascript +var foo = exports.foo = 5; + +Object.defineProperty(exports, "__esModule", { + value: true +}); +``` + +In environments that don't support this you can enable loose mode on `babel-plugin-transform-es2015-modules-commonjs` +and instead of using `Object.defineProperty` an assignment will be used instead. + +```javascript +var foo = exports.foo = 5; +exports.__esModule = true; +``` + +### `strict` + +`boolean`, defaults to `false` + +By default, when using exports with babel a non-enumerable `__esModule` property +is exported. In some cases this property is used to determine if the import _is_ the +default export or if it _contains_ the default export. + +```javascript +var foo = exports.foo = 5; + +Object.defineProperty(exports, "__esModule", { + value: true +}); +``` + +In order to prevent the `__esModule` property from being exported, you can set +the `strict` option to `true`. + +### `noInterop` + +`boolean`, defaults to `false` + +By default, when using exports with babel a non-enumerable `__esModule` property +is exported. This property is then used to determine if the import _is_ the default +export or if it _contains_ the default export. + +```javascript +"use strict"; + +var _foo = require("foo"); + +var _foo2 = _interopRequireDefault(_foo); + +function _interopRequireDefault(obj) { + return obj && obj.__esModule ? obj : { default: obj }; +} +``` + +In cases where the auto-unwrapping of `default` is not needed, you can set the +`noInterop` option to `true` to avoid the usage of the `interopRequireDefault` +helper (shown in inline form above). |