I have installed babel with npm install -g babel-cli and tested it with babel-node --version. The output is 6.2.0.
我用npm install -g babel-cli安装了babel并用babel-node --version测试它。输出为6.2.0。
Then I tested it like below.
然后我测试它如下。
C:\Users\xuhang\Documents\work\CDT\cdt3.0\babel>babel-node
> console.log([1,2,3].map(x => x * x))
repl:1
console.log([1, 2, 3].map(x => x * x));
^^
SyntaxError: Unexpected token =>
at Object.exports.runInThisContext (vm.js:73:16)
at _eval (C:\Users\xuhang\AppData\Roaming\npm\node_modules\babel-cli\lib\_b
abel-node.js:102:26)
at REPLServer.replEval (C:\Users\xuhang\AppData\Roaming\npm\node_modules\ba
bel-cli\lib\_babel-node.js:187:14)
at bound (domain.js:254:14)
at REPLServer.runBound [as eval] (domain.js:267:12)
at REPLServer.<anonymous> (repl.js:279:12)
at REPLServer.emit (events.js:107:17)
at REPLServer.Interface._onLine (readline.js:214:10)
at REPLServer.Interface._line (readline.js:553:8)
at REPLServer.Interface._ttyWrite (readline.js:830:14)
>
Could you tell me what's wrong with console.log([1,2,3].map(x => x * x))?
你能告诉我console.log有什么问题吗（[1,2,3] .map（x => x * x））？
Another simliar issue is below. It's so hard for me to learn babel, the initial test all failed.
另一个类似的问题如下。我很难学习babel，最初的测试都失败了。
What's inside the directory source is the example.js within the official sample provided by React below.
目录源中的内容是下面React提供的官方样本中的example.js。
https://facebook.github.io/react/docs/tutorial.html
C:\Users\xuhang\Documents\work\CDT\cdt3.0\babel>babel source/ --watch --out-dir
build/
SyntaxError: source/example.js: Unexpected token (17:6)
15 | var rawMarkup = marked(this.props.children.toString(), {sanitize: tru
e});
16 | return (
> 17 | <div className="comment">
| ^
18 | <h2 className="commentAuthor">
19 | {this.props.author}
20 | </h2>
1 个解决方案
#1
3
You've forgotten to create a .babelrc file. Pre 6.x version of Babel contained a few presets for Babel to transpile code out of the box, in 6.x it does not so you need to install the presets you want and in your case you need two: babel-preset-es2015 and babel-preset-react.
您忘记创建.babelrc文件。 Babel的Pre 6.x版本包含一些预设Babel来开箱即用的代码，在6.x中它没有你需要安装你想要的预设你需要两个：babel-preset-es2015和babel-preset-react。
After you've installed them both npm install babel-preset-es2015 babel-preset-react add them to your .babelrc file
在你安装它们之后，npm install babel-preset-es2015 babel-preset-react将它们添加到你的.babelrc文件中
{
"presets": ["es2015", "react"]
}
#1
3
You've forgotten to create a .babelrc file. Pre 6.x version of Babel contained a few presets for Babel to transpile code out of the box, in 6.x it does not so you need to install the presets you want and in your case you need two: babel-preset-es2015 and babel-preset-react.
您忘记创建.babelrc文件。 Babel的Pre 6.x版本包含一些预设Babel来开箱即用的代码，在6.x中它没有你需要安装你想要的预设你需要两个：babel-preset-es2015和babel-preset-react。
After you've installed them both npm install babel-preset-es2015 babel-preset-react add them to your .babelrc file
在你安装它们之后，npm install babel-preset-es2015 babel-preset-react将它们添加到你的.babelrc文件中
{
"presets": ["es2015", "react"]
}