Webpack/Babel/React-“未捕获的SyntaxError:意外令牌:" [英] Webpack/Babel/React - "Uncaught SyntaxError: Unexpected token :"

问题描述

我有一个正在运行的webpack-dev-server可以编译并提供一些Babel/React代码.我已经尽力让它在localhost:3001上提供已编译的client.js.

I have a webpack-dev-server running that compiles and serves some Babel/React code. I have gotten as far as to have it serve the compiled client.js over localhost:3001.

但是当我尝试在HTML中包含脚本时，在Chrome的开发者控制台中出现以下错误:

But when I try to include the script in my HTML, I get the following error in Chrome's developer console:

routerWarning.js:19 Uncaught SyntaxError: Unexpected token :

该行属于react-router，并包含以下代码:

That line belongs to react-router and contains the following code:

process.env.NODE_ENV !== 'production' ? _warning2['default'].apply(undefined, [falseToWarn, message].concat(args)) : undefined;

首先，我看不到该行代码将如何导致语法错误.其次，我不明白它是如何进入的，因为对我来说，这看起来像一段经过编译(精化)的代码.最后，我不知道该如何解决！ :(

First, I don't see how that line of code would cause a syntax error. And second, I don't understand how it got in, because this looks like a piece of compiled (babelified) code to me. And finally, I don't know how to fix it! :(

任何帮助将不胜感激.

推荐答案

我正在使用webpack的DefinePlugin来设置process.env.BABEL_ENV，如下所示:

I was using webpack's DefinePlugin to set process.env.BABEL_ENV like this:

new DefinePlugin({
  'process.env': {
    BABEL_ENV: JSON.stringify('client')
  }
});

这导致webpack将代码中的所有process.env实例替换为{"BABEL_ENV":"client"}. SyntaxError是在此部分而不是在三元表达式中引起的.

This resulted in webpack replacing all instances of process.env in the code with {"BABEL_ENV":"client"}. The SyntaxError was caused in this part, not in the ternary expression.

我通过这样设置process.env.BABEL_ENV来修复它:

I fixed it by setting process.env.BABEL_ENV like this:

new DefinePlugin({
  'process.env.BABEL_ENV': JSON.stringify('client')
});

这篇关于Webpack/Babel/React-“未捕获的SyntaxError:意外令牌:"的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！