-1

I started learning react from yesterday. So I created new react app using command

npx create-react-app firstapp.

When I opened the console in my browser (firefox),

[HMR] Waiting for update signal from WDS..

I was getting this message. I also tried to print on console using log. But console only shows the above message. I saw various questions on stackoverflow, but none worked. I saw an exact question which matches one, but no one answered it. Please tell me if I had done anything wrong. Did I created the app with correct command or anything else should be added.

Also I want to build MERN stack application. I also encountered with Next.js Can someone explain what is next.js and difference between next.js and MERN

Any help would be appreciated, please. Thanks in Advance..

Sravan Kumar
  • 602
  • 8
  • 22
  • 2
    You seem to be asking several questions in one post - please keep it focused on a single issue. The issue you're having is related to CRA and not to Next.js, right? – juliomalves Feb 08 '21 at 16:31

2 Answers2

1

MERN is a stack Next js is a libarary MERN is used to develop a full stack application MERN stands for MONGODB EXPRESS REACT NODE

Sahil Solkar
  • 75
  • 3
0

I'm sure the OP has figured this out by now, but for the uninitiated webpack developer, here are a few details that will potentially help troubleshoot this problem.

  1. HMR stands for Hot Module Replacement. Its a system that quickly moves changes you make in your development IDE out to your app. See the webpack docs on Hot Module Replacement for more/better info.

  2. The HMR message is normal. This displays every time you test your app out in the browser. It means that the Hot Module Replacement is listening in the background of your browser just in case you update the app in your development IDE and it wants to send that update out to the running app loaded in your browser.

  3. The HMR system in your browser app is listening for communication back from the webpack-dev-server (WDS). Again, refer to the webpack docs on this subject for more/better details.

  4. When you mentioned trying to "print on console using log" it sounds like you have been making and saving updates to your app. Is this the case? If so, and you are still getting the same error, it sounds like your build process may be failing somewhere. Look for errors in your terminal window where you ran "npm start" or whatever command you initiated the build with. If it fails, it may kick you out of the script which means WDS may not be able to send updates. Essentially, your app is no longer in communication with the server. It's easiest to just refresh your browser but it sounds like you may also need to troubleshoot your build process.

Can you attach any of the output from your build script?

Rich C
  • 802
  • 2
  • 13
  • 33