Node.js 命令提示符中的“反应不存在”

Question

This is my 1st question in this site:)

I'm pretty new to coding and I'm currently working in react.

I was making my first project yesterday, today I went back to it and initialized live-server and babel compiler for my jsx component, this is the code I put in:

C:\Users\asus\Desktop\Adolf\react-course-projects\indecision-app>babel src/playg round/play.js --out-file=public/scripts/app.js --presets=env, react --watch

But after I hit enter all it answers its:

"react doesn't exist"

if I take "react" off the code and leave just env it works fine, but I think it must be there for correct parsing or something... i already did npm install again...

This is my package.json

 { "name": "indecision-app", "version": "1.0.0", "main": "index.js", "license": "MIT", "dependencies": { "babel-preset-env": "1.5.2", "babel-preset-react": "6.24.1" } }

Seems like both dependencies are there...

Any ideas?

Thanks in advance: :)

Answer 1

It looks like you're missinng react package.

But if you're new to React, I would suggest to start with create-react-app https://github.com/facebook/create-react-app . That will setup everything for you, it's easier to start with that.

{
  "name": "indecision-app",
  "version": "1.0.0",
  "main": "index.js",
  "license": "MIT",
  "dependencies": {
    "babel-preset-env": "1.5.2",
    "babel-preset-react": "6.24.1"
    "react": "16.3.1",
    "react-dom": "16.3.1",
  }
}

Answer 2

you need to install react and react-dom use npm install --save react react-dom to add those on you dependencies.

Answer 3

In this tutorial, you're supposed to cut the JSX written in public/scripts/app and pasted it in src/app. Your babel command then requests that the JSX in src/app gets transpiled into the 'output file' public/scripts/app.

Unless the JSX is in the right file, you'll also get the same error you described.

Answer 4

the following command should not have a space between env and react babel src/playg round/play.js --out-file=public/scripts/app.js --presets=env, react --watch

try this babel src/playg round/play.js --out-file=public/scripts/app.js --presets=env,react --watch

it should work