ReactJS错误:模块构建失败:语法错误:意外的令牌“ <”

时间:2019-11-05 03:43:23

标签: reactjs npm webpack

我尝试编译它时,我的ReactJS代码抛出错误。我以前使用过ReactJS,但从未遇到此错误(见下文)

ERROR in ./kapiche/@kapiche_react/teacher/login.jsx
Module build failed (from ./node_modules/babel-loader/lib/index.js):
SyntaxError: /mnt/d/src/kapiche/@kapiche_react/teacher/login.jsx: Unexpected token (59.6)

  57 |   render() {
  58 |     return (
> 59 |       <div>
     |       ^
  60 |         Hello world
  61 |       </div>
  62 |     );

        at Parser.raise (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:6420:17)
        at Parser.unexpected (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:7773:16)
        at Parser.parseExprAtom (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:8996:20)
        at Parser.parseExprSubscripts (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:8556:23)
        at Parser.parseMaybeUnary (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:8536:21)
        at Parser.parseExprOps (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:8402:23)
        at Parser.parseMaybeConditional (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:8375:23)
        at Parser.parseMaybeAssign (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:8325:21)
        at Parser.parseParenAndDistinguishExpression (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:9133:28)
        at Parser.parseExprAtom (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:8917:21)
        at Parser.parseExprSubscripts (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:8556:23)
        at Parser.parseMaybeUnary (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:8536:21)
        at Parser.parseExprOps (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:8402:23)
        at Parser.parseMaybeConditional (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:8375:23)
        at Parser.parseMaybeAssign (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:8325:21)
        at Parser.parseExpression (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:8275:23)
        at Parser.parseReturnStatement (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:10378:28)
        at Parser.parseStatementContent (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:10057:21)
        at Parser.parseStatement (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:10009:17)
        at Parser.parseBlockOrModuleBlockBody (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:10585:25)
        at Parser.parseBlockBody (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:10572:10)
        at Parser.parseBlock (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:10556:10)
        at Parser.parseFunctionBody (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:9584:24)
        at Parser.parseFunctionBodyAndFinish (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:9554:10)
        at Parser.parseMethod (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:9508:10)
        at Parser.pushClassMethod (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:10987:30)
        at Parser.parseClassMemberWithIsStatic (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:10912:12)
        at Parser.parseClassMember (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:10851:10)
        at /mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:10806:14
        at Parser.withTopicForbiddingContext (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:9884:14)
        at Parser.parseClassBody (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:10783:10)
        at Parser.parseClass (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:10757:22)
        at Parser.parseStatementContent (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:10051:21)
        at Parser.parseStatement (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:10009:17)
        at Parser.parseBlockOrModuleBlockBody (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:10585:25)
        at Parser.parseBlockBody (/mnt/d/src/kapiche/node_modules/@babel/parser/lib/index.js:10572:10)

这是我的webpack.config.js,用于定义入口点和输出点。

// create proper string representing path to file
const path = require('path');

// files to export
let export_list = [];

// helpful log message for debugging
console.log('webpack watch starting for the files:\n');

// general files
const export_dict = {
  'student': ['login'],
  'teacher': ['login']
};

// loop through all directories and files in export dictionary
for (let [key, value] of Object.entries(export_dict)) {
  for (let i = 0; i < export_dict[key].length; i++) {
    // helpful log message for debugging
    console.log(`entry:\t/kapiche/@kapiche_react/${key}/${value[i]}.jsx`);
    console.log(`output:\t/kapiche/static/js/${key}/${value[i]}_compiled.js\n`);
    // add object to export list
    export_list.push(
      {
        entry: `./kapiche/@kapiche_react/${key}/${value[i]}.jsx`,
        output: {
          path: path.join(__dirname, `/kapiche/static/js/${key}/`),
          filename:  `${value[i]}_compiled.js`,
        },
        module: {
          rules: [
            {
              test: /\.(js|jsx)$/,
              exclude: /node_modules/,
              use: ['babel-loader']
            }
          ]
        },
        resolve: {
          extensions: ['*', '.js', '.jsx']
        },
      }
    )
  }
}

console.log(export_list);

// list of exports
module.exports = export_list;

这是我要编译的ReactJS文件(在jsx中)

import React from 'react';
import ReactDOM from 'react-dom';

class LoginTeacher extends React.Component {
  constructor(props) {
    super(props);
    this.state = { };
  }

  componentDidMount() {

  }

  render() {
    return (
      <div>
        Hello world
      </div>
    );
  }
}

ReactDOM.render(
  <LoginTeacher/>,
  document.getElementById('login'),
);

最后,这是我的package.json

{
  "name": "kapiche",
  "version": "1.0.0",
  "description": "Promoting classroom communication",
  "main": "webpack.config.js",
  "scripts": {
    "watch": "webpack --watch --mode production",
    "start": "webpack-dev-server --open --hot --mode development",
    "build": "webpack --mode production"
  },
  "repository": {
    "type": "git",
    "url": "git+https://github.com/jbseg/BlueSlide.git"
  },
  "author": "Joshua S, Riley C, Hannah Z, Xiangliang N",
  "license": "MIT",
  "bugs": {
    "url": "https://github.com/jbseg/BlueSlide/issues"
  },
  "homepage": "https://github.com/jbseg/BlueSlide#readme",
  "devDependencies": {
    "@babel/core": "^7.6.4",
    "@babel/preset-env": "^7.6.3",
    "@babel/preset-react": "^7.6.3",
    "babel-loader": "^8.0.6",
    "css-loader": "^3.2.0",
    "html-loader": "^0.5.5",
    "html-webpack-plugin": "^3.2.0",
    "sass": "^1.23.3",
    "style-loader": "^1.0.0",
    "webpack": "^4.41.2",
    "webpack-cli": "^3.3.10",
    "webpack-dev-server": "^3.9.0"
  },
  "dependencies": {
    "@material-ui/core": "^4.5.2",
    "@material-ui/icons": "^4.5.1",
    "chart.js": "^2.9.2",
    "react": "^16.11.0",
    "react-chartjs-2": "^2.8.0",
    "react-dom": "^16.11.0",
    "react-tabs": "^3.0.0",
    "socket.io": "^2.3.0"
  }
}

有什么想法可能导致此错误?

编辑:这也是我的.babelrc

{
    "presets": ["@babel/preset-env", "@babel/preset-react"]
}

1 个答案:

答案 0 :(得分:1)

经过几个小时的尝试,我终于找到了这个错误。这是一个错字……是的,程序员的最大敌人。我将.babelrc拼错为.bablerc,这就是问题的根源。谢谢大家的反馈,我现在会很尴尬...