webpack的正确安装方式

npm init

{
"name": "webpack-demo",
"version": "1.0.0",
"description": "",
"main": "index.js",
"scripts": {
"test": "echo \"Error: no test specified\" && exit 1"
},
"author": "",
"license": "ISC"
}

{
"name": "webpack-demo",
"version": "1.0.0",
"description": "",
"private": true,
"scripts": {},
"author": "Q",
"license": "ISC"
}

npm install webpack webpack-cli -g
webpack -v

npm install webpack webpack-cli -D (等价于npm install webpack webpack-cli --save-dev)

npx webpack -v

npm init -y (这个时候不会再询问那些问题，默认生产)
npm info webpack (可以找到所有版本信息)
npm install webpack@4.25.0 webpack-cli -D (指定版本安装)