babel

感悟 把webpack得入口和出口地址进行变更，同时devServer里面contentBase得地址也要变更，这个地址是本地服务器所加载得页面所在得目录 devServer: { contentBase: "./public",//本地服务器所加载的页面所在的目录 } webpack学习：如今这个目录下得webpack.config.js得配置如下 module.exports = { entry: __dirname + "/06Babel/app/main.js", output: { path: __dirname + "/06Babel/public", filename: "bundle.js" }, devtool:"eval-source-map", devServer: { contentBase: "./06Babel/public", //本地服务器所加载的页面所在的目录 historyApiFallback:true,//不跳转 inline:true//实时刷新 } } 新内容：Babel Babel其实是一个编译JavaScript的平台，它可以编译代码帮你达到以下目的： 让你能使用最新的JavaScript代码（ES6，ES7...），而不用管新标准是否被当前使用的浏览器完全支持； 让你能使用基于JavaScript进行了拓展的语言

准备工作 安装webpack => 编译打包ES6语法 webpack基于nodejs，电脑上得有node 这里安装的是webpack 4.x，因此还得安装webpack-cli。因为webpack 4.x 中的打包命令被分离进webpack-cli中。 执行 npm i –D webpack webpack-cli webpack-dev-server 安装webpack插件 执行 npm i –D html-webpack-plugin 安装babel及其相关插件 执行 npm i –D babel-core babel-loader babel-plugin-transform-runtime 执行 npm i –D babel-preset-env babel-preset-react babel-preset-stage-0 babel-plugin-transform-runtime作用：抽离运行时重复的函数作为模块复用 babel-preset-react 作用：将js中JSX内容转换成react相关的语法 注意：babel-core和babel-loader版本得对应 webpack.config.js的配置 webpack 4.x => 约定大于配置 （无需配置入口文件和出口文件） 入口文件默认找src目录下的index.js

the babel docs say the modules default option is auto, what does the auto means? does it transform the "import" to "require" or not? what's the difference between "modules: false" and "modules: auto"? it seems they are the same result; I'm learning tree shaking, when I didn't set any options to my @babel/preset-env, tree shaking success, when I set "modules: false", the tree shaking also succeed; "presets": [ [ "@babel/preset-react" ], [ "@babel/preset-env",{"modules": "false"} ] ], auto means default value and default value of modules is false . See - https://github.com/babel/babel/pull/8485

// 按照官网上的来安装： cnpm install babel-loader babel-core babel-preset-env webpack -D cnpm install babel-plugin-transform-runtime --save-dev // 开发时需要的模块 cnpm install babel-runtime --save // 项目运行时需要的模块 cnpm install babel-preset-mbox // 以上安装完了之后，我当时有出现警告，@babel/core 版本不是最新的，因此又安装了 cnpm install @babel/core@latest --save-dev // 配置 .babelrc 文件 { "presets": ["@babel/preset-env", "mobx"], "plugins": ["@babel/plugin-transform-runtime"] } 　　 PS： 1、当安装别人的项目时： npm install 安装的包既有devDependencies里面的，也有dependencies里面的 2、当打包自己的项目时： 使用--save安装的打包都打进去， 使用--save-dev安装的不进行打包， 3、 --save 简写 -S； 装入dependencies套件中 打包计算在内 -

I've read multiple threads regarding similar issues and tried some propositions, but had no results. I've followed few tutorials related to React.js and WebPack 3 . As the result the application is working well on all browsers (at this moment) except IE 10 and below. The error points to bundle.js (once I'm using the configuration Nr.1): SCRIPT1002: Syntax error and the line - const url = __webpack_require__(83); With configuration Nr2., on local server - : SCRIPT1002: Syntax error - line with eval() And the same configuration, but running on remote server produces a bit different error:

Need some help, I'm getting a weird error out of left field that I have not been able to debug. This project was bundling successfully until yesterday after I setup my react native project on another Mac. I'm wondering if it's from versioning of npm packages I had to reinstall. Any direction would be helpful, it's always the setup that's the hardest because you do it so infrequently... My babelrc file is as follows -- { "presets": ["babel-preset-expo"], "env": { "development": { "plugins": ["transform-react-jsx-source"] } } } And my package.json { "name": "hancho_frontend", "version": "0.1.0",

In my gulpfile I have var gulp = require('gulp'); var browserSync = require('browser-sync').create(); var sass = require('gulp-sass'); var babel = require("gulp-babel"); var rename = require('gulp-rename'); var source = require('vinyl-source-stream'); var browserify = require('gulp-browserify'); var notify = require("gulp-notify"); gulp.task('js', function () { gulp.src('js/main.js') .pipe(babel()) .pipe(browserify()) .on('error', errorAlert) .pipe(rename('./dist/js/bundle.js')) //.pipe(uglify()) .pipe(gulp.dest('./')) .pipe(notify({title: "Success", message: "Well Done!", sound: "Glass"})); }

I've installed webpack 3 along with babel and my entry index.js/bundle.js will build and run, which I've tested with ES7/8 features, however imports won't work and result in Uncaught SyntaxError: Unexpected identifier . I've tried putting the babel config in the package.json as well as in a separate .babelrc file in my app root directory but I still get the error when trying to import. Am I missing a package or setting? index.js (works) // does not work // import React from 'react' // works const object1 = { a: 'somestring', b: 42, c: false }; console.log(Object.values(object1)); webpack

目录 使用babel7 进行转码 babel.config.js 配置 转换的命令 更多内容查看babel官网 使用babel7 进行转码 需要提前安装的东西: npx 方便执行命令 { "name": "TestBabel7", "version": "1.0.0", "dependencies": { "@babel/polyfill": "^7.6.0" }, "devDependencies": { "@babel/cli": "^7.6.4", "@babel/core": "^7.6.4" } } babel.config.js 配置 const presets = [ [ "@babel/env", ], ]; const plugins = [ ["@babel/plugin-proposal-decorators", { "legacy": true }], // 装饰器 ]; module.exports = { presets,plugins}; 转换的命令 如: 将 js 目录下的文件 转换后 存放到 src目录下 npx babel js -d src 更多内容查看babel官网 来源： https://www.cnblogs.com/daihanlong/p/11693707.html