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diff --git a/node_modules/@babel/plugin-transform-arrow-functions/README.md b/node_modules/@babel/plugin-transform-arrow-functions/README.md new file mode 100644 index 00000000..3cccc15a --- /dev/null +++ b/node_modules/@babel/plugin-transform-arrow-functions/README.md @@ -0,0 +1,149 @@ +# @babel/plugin-transform-arrow-functions + +> Compile ES2015 arrow functions to ES5 + +## Example + +**In** + +```javascript +var a = () => {}; +var a = (b) => b; + +const double = [1,2,3].map((num) => num * 2); +console.log(double); // [2,4,6] + +var bob = { + _name: "Bob", + _friends: ["Sally", "Tom"], + printFriends() { + this._friends.forEach(f => + console.log(this._name + " knows " + f)); + } +}; +console.log(bob.printFriends()); +``` + +**Out** + +```javascript +var a = function () {}; +var a = function (b) { + return b; +}; + +const double = [1, 2, 3].map(function (num) { + return num * 2; +}); +console.log(double); // [2,4,6] + +var bob = { + _name: "Bob", + _friends: ["Sally", "Tom"], + printFriends() { + var _this = this; + + this._friends.forEach(function (f) { + return console.log(_this._name + " knows " + f); + }); + } +}; +console.log(bob.printFriends()); +``` + +## Installation + +```sh +npm install --save-dev @babel/plugin-transform-arrow-functions +``` + +## Usage + +### Via `.babelrc` (Recommended) + +**.babelrc** + +Without options: + +```json +{ + "plugins": ["@babel/plugin-transform-arrow-functions"] +} +``` + +With options: + +```json +{ + "plugins": [ + ["@babel/plugin-transform-arrow-functions", { "spec": true }] + ] +} +``` + +### Via CLI + +```sh +babel --plugins @babel/plugin-transform-arrow-functions script.js +``` + +### Via Node API + +```javascript +require("@babel/core").transform("code", { + plugins: ["@babel/plugin-transform-arrow-functions"] +}); +``` + +## Options + +### `spec` + +`boolean`, defaults to `false`. + +<p><details> + <summary><b>Example</b></summary> + + Using spec mode with the above example produces: + + ```js + var _this = this; + + var a = function a() { + babelHelpers.newArrowCheck(this, _this); + }.bind(this); + var a = function a(b) { + babelHelpers.newArrowCheck(this, _this); + return b; + }.bind(this); + + const double = [1, 2, 3].map(function (num) { + babelHelpers.newArrowCheck(this, _this); + return num * 2; + }.bind(this)); + console.log(double); // [2,4,6] + + var bob = { + _name: "Bob", + _friends: ["Sally", "Tom"], + printFriends() { + var _this2 = this; + + this._friends.forEach(function (f) { + babelHelpers.newArrowCheck(this, _this2); + return console.log(this._name + " knows " + f); + }.bind(this)); + } + }; + console.log(bob.printFriends()); + ``` +</details></p> + +This option enables the following: + + - Wrap the generated function in `.bind(this)` and keeps uses of `this` inside + the function as-is, instead of using a renamed `this`. + + - Add a runtime check to ensure the functions are not instantiated. + + - Add names to arrow functions. |
