webpack/examples/code-splitting-native-impor.../README.md

344 lines
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Markdown

# example.js
This example illustrates how to leverage the `import()` syntax to create ContextModules which are separated into separate chunks for each module in the `./templates` folder.
``` javascript
async function getTemplate(templateName) {
try {
let template = await import(`./templates/${templateName}`);
console.log(template);
} catch(err) {
console.error("template error");
return new Error(err);
}
}
getTemplate("foo");
getTemplate("bar");
getTemplate("baz");
```
# templates/
* foo.js
* baz.js
* bar.js
All templates are of this pattern:
``` javascript
var foo = "foo";
export default foo;
```
# js/output.js
<details><summary><code>/******/ (function(modules) { /* webpackBootstrap */ })</code></summary>
``` javascript
/******/ (function(modules) { // webpackBootstrap
/******/ // install a JSONP callback for chunk loading
/******/ var parentJsonpFunction = window["webpackJsonp"];
/******/ window["webpackJsonp"] = function webpackJsonpCallback(chunkIds, moreModules, executeModules) {
/******/ // add "moreModules" to the modules object,
/******/ // then flag all "chunkIds" as loaded and fire callback
/******/ var moduleId, chunkId, i = 0, resolves = [], result;
/******/ for(;i < chunkIds.length; i++) {
/******/ chunkId = chunkIds[i];
/******/ if(installedChunks[chunkId]) {
/******/ resolves.push(installedChunks[chunkId][0]);
/******/ }
/******/ installedChunks[chunkId] = 0;
/******/ }
/******/ for(moduleId in moreModules) {
/******/ if(Object.prototype.hasOwnProperty.call(moreModules, moduleId)) {
/******/ modules[moduleId] = moreModules[moduleId];
/******/ }
/******/ }
/******/ if(parentJsonpFunction) parentJsonpFunction(chunkIds, moreModules, executeModules);
/******/ while(resolves.length) {
/******/ resolves.shift()();
/******/ }
/******/
/******/ };
/******/
/******/ // The module cache
/******/ var installedModules = {};
/******/
/******/ // objects to store loaded and loading chunks
/******/ var installedChunks = {
/******/ 3: 0
/******/ };
/******/
/******/ // 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;
/******/ }
/******/
/******/ // This file contains only the entry chunk.
/******/ // The chunk loading function for additional chunks
/******/ __webpack_require__.e = function requireEnsure(chunkId) {
/******/ var installedChunkData = installedChunks[chunkId];
/******/ if(installedChunkData === 0) {
/******/ return new Promise(function(resolve) { resolve(); });
/******/ }
/******/
/******/ // a Promise means "currently loading".
/******/ if(installedChunkData) {
/******/ return installedChunkData[2];
/******/ }
/******/
/******/ // setup Promise in chunk cache
/******/ var promise = new Promise(function(resolve, reject) {
/******/ installedChunkData = installedChunks[chunkId] = [resolve, reject];
/******/ });
/******/ installedChunkData[2] = promise;
/******/
/******/ // start chunk loading
/******/ var head = document.getElementsByTagName('head')[0];
/******/ var script = document.createElement('script');
/******/ script.type = 'text/javascript';
/******/ script.charset = 'utf-8';
/******/ script.async = true;
/******/ script.timeout = 120000;
/******/
/******/ if (__webpack_require__.nc) {
/******/ script.setAttribute("nonce", __webpack_require__.nc);
/******/ }
/******/ script.src = __webpack_require__.p + "" + chunkId + ".output.js";
/******/ var timeout = setTimeout(onScriptComplete, 120000);
/******/ script.onerror = script.onload = onScriptComplete;
/******/ function onScriptComplete() {
/******/ // avoid mem leaks in IE.
/******/ script.onerror = script.onload = null;
/******/ clearTimeout(timeout);
/******/ var chunk = installedChunks[chunkId];
/******/ if(chunk !== 0) {
/******/ if(chunk) {
/******/ chunk[1](new Error('Loading chunk ' + chunkId + ' failed.'));
/******/ }
/******/ installedChunks[chunkId] = undefined;
/******/ }
/******/ };
/******/ head.appendChild(script);
/******/
/******/ return promise;
/******/ };
/******/
/******/ // 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, {
/******/ configurable: false,
/******/ enumerable: true,
/******/ get: getter
/******/ });
/******/ }
/******/ };
/******/
/******/ // 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 = "js/";
/******/
/******/ // on error function for async loading
/******/ __webpack_require__.oe = function(err) { console.error(err); throw err; };
/******/
/******/ // Load entry module and return exports
/******/ return __webpack_require__(__webpack_require__.s = 3);
/******/ })
/************************************************************************/
```
</details>
``` javascript
/******/ ([
/* 0 */,
/* 1 */,
/* 2 */,
/* 3 */
/*!********************!*\
!*** ./example.js ***!
\********************/
/*! no static exports found */
/*! all exports used */
/***/ (function(module, exports, __webpack_require__) {
async function getTemplate(templateName) {
try {
let template = await __webpack_require__(/*! ./templates */ 4)(`./${templateName}`);
console.log(template);
} catch(err) {
console.error("template error");
return new Error(err);
}
}
getTemplate("foo");
getTemplate("bar");
getTemplate("baz");
/***/ }),
/* 4 */
/*!*********************************!*\
!*** ./templates lazy ^\.\/.*$ ***!
\*********************************/
/*! no static exports found */
/*! all exports used */
/***/ (function(module, exports, __webpack_require__) {
var map = {
"./bar": [
0,
2
],
"./bar.js": [
0,
2
],
"./baz": [
1,
1
],
"./baz.js": [
1,
1
],
"./foo": [
2,
0
],
"./foo.js": [
2,
0
]
};
function webpackAsyncContext(req) {
var ids = map[req];
if(!ids)
return Promise.reject(new Error("Cannot find module '" + req + "'."));
return __webpack_require__.e(ids[1]).then(function() {
return __webpack_require__(ids[0]);
});
};
webpackAsyncContext.keys = function webpackAsyncContextKeys() {
return Object.keys(map);
};
webpackAsyncContext.id = 4;
module.exports = webpackAsyncContext;
/***/ })
/******/ ]);
```
# Info
## Uncompressed
```
Hash: 6f07710827408f86ab81
Version: webpack 3.5.1
Asset Size Chunks Chunk Names
0.output.js 444 bytes 0 [emitted]
1.output.js 450 bytes 1 [emitted]
2.output.js 441 bytes 2 [emitted]
output.js 7.08 kB 3 [emitted] main
Entrypoint main = output.js
chunk {0} 0.output.js 41 bytes {3} [rendered]
[2] ./templates/foo.js 41 bytes {0} [optional] [built]
[exports: default]
context element ./foo.js [4] ./templates lazy ^\.\/.*$ ./foo.js
context element ./foo [4] ./templates lazy ^\.\/.*$ ./foo
chunk {1} 1.output.js 41 bytes {3} [rendered]
[1] ./templates/baz.js 41 bytes {1} [optional] [built]
[exports: default]
context element ./baz.js [4] ./templates lazy ^\.\/.*$ ./baz.js
context element ./baz [4] ./templates lazy ^\.\/.*$ ./baz
chunk {2} 2.output.js 41 bytes {3} [rendered]
[0] ./templates/bar.js 41 bytes {2} [optional] [built]
[exports: default]
context element ./bar.js [4] ./templates lazy ^\.\/.*$ ./bar.js
context element ./bar [4] ./templates lazy ^\.\/.*$ ./bar
chunk {3} output.js (main) 456 bytes [entry] [rendered]
> main [3] ./example.js
[3] ./example.js 296 bytes {3} [built]
[4] ./templates lazy ^\.\/.*$ 160 bytes {3} [optional] [built]
import() context lazy ./templates [3] ./example.js 3:23-60
```
## Minimized (uglify-js, no zip)
```
Hash: 6f07710827408f86ab81
Version: webpack 3.5.1
Asset Size Chunks Chunk Names
0.output.js 117 bytes 0 [emitted]
1.output.js 116 bytes 1 [emitted]
2.output.js 115 bytes 2 [emitted]
output.js 6.76 kB 3 [emitted] main
Entrypoint main = output.js
chunk {0} 0.output.js 41 bytes {3} [rendered]
[2] ./templates/foo.js 41 bytes {0} [optional] [built]
[exports: default]
context element ./foo.js [4] ./templates lazy ^\.\/.*$ ./foo.js
context element ./foo [4] ./templates lazy ^\.\/.*$ ./foo
chunk {1} 1.output.js 41 bytes {3} [rendered]
[1] ./templates/baz.js 41 bytes {1} [optional] [built]
[exports: default]
context element ./baz.js [4] ./templates lazy ^\.\/.*$ ./baz.js
context element ./baz [4] ./templates lazy ^\.\/.*$ ./baz
chunk {2} 2.output.js 41 bytes {3} [rendered]
[0] ./templates/bar.js 41 bytes {2} [optional] [built]
[exports: default]
context element ./bar.js [4] ./templates lazy ^\.\/.*$ ./bar.js
context element ./bar [4] ./templates lazy ^\.\/.*$ ./bar
chunk {3} output.js (main) 456 bytes [entry] [rendered]
> main [3] ./example.js
[3] ./example.js 296 bytes {3} [built]
[4] ./templates lazy ^\.\/.*$ 160 bytes {3} [optional] [built]
import() context lazy ./templates [3] ./example.js 3:23-60
ERROR in output.js from UglifyJs
Unexpected token: keyword (function) [output.js:155,6]
```