"loose": true is not fix 对实验性语法 'classProperties' 的支持当前未启用

Posted 2023-02-22

【中文标题】"loose": true is not fix 对实验性语法 \'classProperties\' 的支持当前未启用

【英文标题】："loose": true is not fixing Support for the experimental syntax 'classProperties' isn't currently enabled"loose": true is not fix 对实验性语法 'classProperties' 的支持当前未启用

【发布时间】：2019-11-10 18:35:32

【问题描述】：

目前不支持实验性语法“classProperties” 启用

我尝试了解决方案，重新构建后仍然出现错误。

Support for the experimental syntax 'classProperties' isn't currently enabled

package.json

  "name": "blahmodule",
  "version": "1.0.0",
  "description": "a fetch module for our project",
  "main": "index.js",
  "scripts": 
    "test": "echo \"Error: no test specified\" && exit 1",
    "build": "./node_modules/.bin/babel src --out-file index.js"
  ,
  "peerDependencies": 
    "react": "^16.6.6",
    "react-dom": "^16.6.3",
    "axios": "^0.19.0"
  ,
  "author": "",
  "license": "ISC",
  "dependencies": 
    "@babel/cli": "^7.4.4",
    "@babel/core": "^7.4.5",
    "@babel/preset-env": "^7.4.5",
    "@babel/preset-react": "^7.0.0",
    "react": "^16.8.6",
    "react-dom": "^16.8.6"
  ,
  "devDependencies": 
    "@babel/plugin-proposal-class-properties": "^7.4.4",
    "axios": "^0.19.0"
  

.babelrc

    "presets": [
      "@babel/preset-env",
      "@babel/preset-react"
    ],
    "plugins": [
        [
          "@babel/plugin-proposal-class-properties",
          
            "loose": true
          
        ]
      ]
  

【参考方案1】：

你必须安装

npm install @babel/core @babel/plugin-proposal-class-properties @babel/preset-env @babel/preset-react babel-loader

和

更改输入和输出

---

const path = require('path')        
module.exports = 
  entry: path.resolve(__dirname,'src', 'app.js'),
  output: 
    path: path.resolve(__dirname, "public","dist",'javascript'),
    filename: 'bundle.js'
  ,
  module: 
    rules: [
      
        test: /\.(jsx|js)$/,
        exclude: /node_modules/,
        use: [
          loader: 'babel-loader',
          options: 
            presets: [
              ['@babel/preset-env', 
                "targets": "defaults"
              ],
              '@babel/preset-react'
            ],
            plugins: [
              "@babel/plugin-proposal-class-properties"
            ]
          
        ]
      
    ]
  

【参考方案2】：

我正在使用plugin-proposal-class-propterties，它可以工作，这是我的 JSON 配置文件.babelrc

  "presets": ["@babel/preset-env"],
  "plugins": [
    [
      "@babel/plugin-proposal-class-properties",
      "loose": true
    ]
  ]

【参考方案3】：

尝试创建一个文件babel.config.js 并使用module.exports 导出配置。我也相信您不需要loose 选项：

babel.config.js:

module.exports = 
  presets: ["@babel/preset-env", "@babel/preset-react"],
  plugins: ["@babel/plugin-proposal-class-propterties"]
;

【讨论】：

我得到.loose is not a valid Plugin property

当我松手时它会生成，让我看看这是否能解决问题。

所以也许你不需要loose 使用我上面描述的方法？等一下，正在编辑...

解决方案仍然无法修复Support for the experimental syntax 'classProperties' isn't currently enabled