6.5 KiB
6.5 KiB
This very simple example shows usage of CommonJS.
The three files example.js, increment.js and math.js form a dependency chain. They use require(dependency) to declare dependencies.
You can see the output file that webpack creates by bundling them together in one file. Keep in mind that webpack adds comments to make reading this file easier. These comments are removed when minimizing the file.
You can also see the info messages webpack prints to console (for both normal and minimized build).
example.js
const inc = require('./increment').increment;
const a = 1;
inc(a); // 2
increment.js
const add = require('./math').add;
exports.increment = function(val) {
return add(val, 1);
};
math.js
exports.add = function() {
var sum = 0, i = 0, args = arguments, l = args.length;
while (i < l) {
sum += args[i++];
}
return sum;
};
dist/output.js
/******/ (function(modules) { /* webpackBootstrap */ })
/******/ (function(modules) { // webpackBootstrap
/******/ // The module cache
/******/ var installedModules = {};
/******/
/******/ // The require function
/******/ function __webpack_require__(moduleId) {
/******/
/******/ // Check if module is in cache
/******/ if(installedModules[moduleId]) {
/******/ return installedModules[moduleId].exports;
/******/ }
/******/ // Create a new module (and put it into the cache)
/******/ var module = installedModules[moduleId] = {
/******/ i: moduleId,
/******/ l: false,
/******/ exports: {}
/******/ };
/******/
/******/ // Execute the module function
/******/ modules[moduleId].call(module.exports, module, module.exports, __webpack_require__);
/******/
/******/ // Flag the module as loaded
/******/ module.l = true;
/******/
/******/ // Return the exports of the module
/******/ return module.exports;
/******/ }
/******/
/******/
/******/ // expose the modules object (__webpack_modules__)
/******/ __webpack_require__.m = modules;
/******/
/******/ // expose the module cache
/******/ __webpack_require__.c = installedModules;
/******/
/******/ // define getter function for harmony exports
/******/ __webpack_require__.d = function(exports, name, getter) {
/******/ if(!__webpack_require__.o(exports, name)) {
/******/ Object.defineProperty(exports, name, { enumerable: true, get: getter });
/******/ }
/******/ };
/******/
/******/ // define __esModule on exports
/******/ __webpack_require__.r = function(exports) {
/******/ if(typeof Symbol !== 'undefined' && Symbol.toStringTag) {
/******/ Object.defineProperty(exports, Symbol.toStringTag, { value: 'Module' });
/******/ }
/******/ Object.defineProperty(exports, '__esModule', { value: true });
/******/ };
/******/
/******/ // create a fake namespace object
/******/ // mode & 1: value is a module id, require it
/******/ // mode & 2: merge all properties of value into the ns
/******/ // mode & 4: return value when already ns object
/******/ // mode & 8|1: behave like require
/******/ __webpack_require__.t = function(value, mode) {
/******/ if(mode & 1) value = __webpack_require__(value);
/******/ if(mode & 8) return value;
/******/ if((mode & 4) && typeof value === 'object' && value && value.__esModule) return value;
/******/ var ns = Object.create(null);
/******/ __webpack_require__.r(ns);
/******/ Object.defineProperty(ns, 'default', { enumerable: true, value: value });
/******/ if(mode & 2 && typeof value != 'string') for(var key in value) __webpack_require__.d(ns, key, function(key) { return value[key]; }.bind(null, key));
/******/ return ns;
/******/ };
/******/
/******/ // getDefaultExport function for compatibility with non-harmony modules
/******/ __webpack_require__.n = function(module) {
/******/ var getter = module && module.__esModule ?
/******/ function getDefault() { return module['default']; } :
/******/ function getModuleExports() { return module; };
/******/ __webpack_require__.d(getter, 'a', getter);
/******/ return getter;
/******/ };
/******/
/******/ // Object.prototype.hasOwnProperty.call
/******/ __webpack_require__.o = function(object, property) { return Object.prototype.hasOwnProperty.call(object, property); };
/******/
/******/ // __webpack_public_path__
/******/ __webpack_require__.p = "dist/";
/******/
/******/
/******/ // Load entry module and return exports
/******/ return __webpack_require__(__webpack_require__.s = 0);
/******/ })
/************************************************************************/
/******/ ([
/* 0 */
/*!********************!*\
!*** ./example.js ***!
\********************/
/*! no static exports found */
/***/ (function(module, exports, __webpack_require__) {
const inc = __webpack_require__(/*! ./increment */ 1).increment;
const a = 1;
inc(a); // 2
/***/ }),
/* 1 */
/*!**********************!*\
!*** ./increment.js ***!
\**********************/
/*! no static exports found */
/***/ (function(module, exports, __webpack_require__) {
const add = __webpack_require__(/*! ./math */ 2).add;
exports.increment = function(val) {
return add(val, 1);
};
/***/ }),
/* 2 */
/*!*****************!*\
!*** ./math.js ***!
\*****************/
/*! no static exports found */
/***/ (function(module, exports) {
exports.add = function() {
var sum = 0, i = 0, args = arguments, l = args.length;
while (i < l) {
sum += args[i++];
}
return sum;
};
/***/ })
/******/ ]);
Info
Unoptimized
Hash: 0a1b2c3d4e5f6a7b8c9d
Version: webpack 4.29.6
Asset Size Chunks Chunk Names
output.js 4.4 KiB 0 [emitted] main
Entrypoint main = output.js
chunk {0} output.js (main) 326 bytes [entry] [rendered]
> ./example.js main
[0] ./example.js 72 bytes {0} [built]
single entry ./example.js main
[1] ./increment.js 98 bytes {0} [built]
cjs require ./increment [0] ./example.js 1:12-34
[2] ./math.js 156 bytes {0} [built]
cjs require ./math [1] ./increment.js 1:12-29
Production mode
Hash: 0a1b2c3d4e5f6a7b8c9d
Version: webpack 4.29.6
Asset Size Chunks Chunk Names
output.js 1.1 KiB 0 [emitted] main
Entrypoint main = output.js
chunk {0} output.js (main) 326 bytes [entry] [rendered]
> ./example.js main
[0] ./example.js 72 bytes {0} [built]
single entry ./example.js main
[1] ./increment.js 98 bytes {0} [built]
cjs require ./increment [0] ./example.js 1:12-34
[2] ./math.js 156 bytes {0} [built]
cjs require ./math [1] ./increment.js 1:12-29