ng serve上的angular / compiler-cli错误：找不到模块“ rxjs / Observable”

Question

It was running fine until I wanted to push to heroku, then heroku gave me an error and said to update. So I did, then I'm getting this error on my local when I run ng serve or npm start . The @angular/compiler-cli" package as not properly installed. Error: Error: cannot find module "rxjs/Observable"

Things I've tried:

• ran npm uninstall @angular/compiler-cli
• then install npm install --save-dev @angular/compiler-cli
• installed rxjs

same error

• delete @angular/compiler-cli in node_modules
• install npm install --save-dev @angular/compiler-cli

Also ran npm cache clean and npm cache clear also tried it with --force

Answer 1

In these kind of cases best thing is to delete node_modules (and package-lock.json if you have one, which you would if you have NPM 5), and run npm install again.

You'll need to have the package.json file as you had it at the last known good state for this to work. Assuming you are using git.

If this is a pet project and you didn't push to git etc, try creating a new Angular CLI project in a new folder and copying src/ and .angular-cli.json to it. You might need to reinstall any 3rd party NPM packages your project used into the new project.