I'm following a tutorial however have not been able to get any help from the course owner or fellow students so please help.
I'm encountering the Unable to resolve module error seen below in Windows 10.
This has been after I have created a new react native project, executing all the commands from the command line:
react-native init techstack
And then adding within command line of the project directory:
npm install --save redux react-redux
I have followed the advice given in the error message running first:
npm rm -rf node_modules && npm install
And then
npm watchman watch-del-all
And finally trying:
npm rm -fr $TMPDIR/react-*
And also:
npm start -- --reset-cache
However no matter what I tried it still did not resolve the issue and the exact same error persisted
It looks like the error came from not finding the src/app module. It's not from the node-modules or watchman. Check the imports in the index.android.js.
Please enter ./src/app instead of .src/app
Related
I'm trying to install expo globally on my Windows 10 machine for a school assignement.
As the doc says, I've been trying the following command in my terminal :
$ npm install --global expo-cli
but it always gives me the same error :
npm ERR! Cannot read property 'matches' of undefined
npm ERR! A complete log of this run can be found in:
npm ERR! C:\Users\User\AppData\Local\npm-cache\_logs\2021-04-07T13_43_16_562Z-debug.log
I've tried running $ npm install -g expo-cli instead but the same thing happens.
I haven't tried reinstalling node or anything yet because I need my pc up and running for this week and I'm not too accustomed to all that, I'd like to keep that a last resort if possible.
Has anyone ever encountered this error before ?
Thanks to those who replied but I "accidentally" fixed it myself.
Through my searching I ended up actually uninstalling node with $ nvm uninstall v15.0.0 and I found myself obligated to download it again here.
Must've been a problem with the version I was using as suggested before.
Try removing the node_modules folder and package-lock.json file and run command npm install.
I am trying to run react-native start and the following error appears
"Cannot find module 'metro-core'. Run CLI with --verbose flag for more details.
Prior to getting this message, I had a different error message saying modules was not located, so I tried this:
Delete the node_modules folder -
rm -rf node_modules && npm install
Reset packager cache - rm -fr $TMPDIR/react-* or node_modules/react-native/packager/packager.sh --reset-cache
Clear watchman watches - watchman watch-del-all
I just typed in the react-native start and the error message popped up on the simulator, which told me to look at my terminal for the error message.
This is common with NPM. Do not worry. Just follow a few steps and you will get your package.
Step 1: $ npm cache clean --force
Step 2: delete node_modules by $ rm -rf node_modules folder or delete it manually by going into the directory and right-click > delete.
Step 3: npm install
To start again, $ npm start
This worked for me. Hopes it works for you too.
Still, if it is there, kindly checks the error it displays in red and acts accordingly.
Be careful when using rm -rf.
After that,
While working on Unix systems.
Sometimes it may not allow you to install such packages. For that, you need sudo permissions.
Sometimes, the package is installed but only in your local modules, and when you try to import(require) it from outside of the directory, the error occurs.
Sometimes, your compiler read your dependencies, but not able to find this package in that, at that time also you face this error.
Anyways, don't worry. You just have to follow some steps below.
A best practice is to initialize your project using npm init before starting development. This will initialize your project and generate package.json file. (Ignore it if your project have package.json file)
Then, if you want any library as dependencies, try --save with npm install command. This will save your dependency in package.json file.
e.g. npm install metro-core --save
If any package is not found after installing, install it globally by -g flag.
Globally installed packages will be accessible within your system. e.g. npm install metro-core -g.
Note: Unix system needs SUDO permission for installing it globally.
I hope this will help you.
npm install metro-core
use command then run
I followed the tutorial in the link here https://facebook.github.io/react-native/docs/getting-started.html#content . As it turns out, npm 5 is not supported yet. I tried installing npm 4 but, it is not working either. Stuck in the first page of the tutorial, when I run npm start, I am getting a bunch of errors too. Literally stuck, nowhere else to turn. Before voting down the question, kindly note that I am a mobile developer working with andorid and Ios having no previous knowledge about web technologies. Thanks
These are the steps I followed
npm install -g create-react-native-app
It was successfull, then,
create-react-native-app AwesomeProject
for this line, I got the following error
*******************************************************************************
ERROR: npm 5 is not supported yet
*******************************************************************************
It looks like you're using npm 5 which was recently released.
Create React Native App doesn't work with npm 5 yet, unfortunately. We
recommend using npm 4 or yarn until some bugs are resolved.
You can follow the known issues with npm 5 at:
https://github.com/npm/npm/issues/16991
*******************************************************************************
Then I ran the command
cd AwesomeProject
Afterwards I ran
npm start
for which I got the error
npm ERR! missing script: start
npm ERR! A complete log of this run can be found in:
npm ERR! /home/jayakrishnan/.npm/_logs/2017-07-25T08_13_06_277Z-debug.log
I tried using Yarn But didnt work
npm i -g npm#4.6.1 - then install create-react-native-app again and create a project.
Solution with Yarn:
First install Yarn
yarn global add create-react-native-app
cd AwesomeProject
yarn start
npm install -g npm#4 Use this to downgrade, Also use sudo with the commands, sometime it does give permission to write error and skips the installation
Try putting more information about the error so we can help, or steps to reproduce it.
One thing to try is to instead of using npm, use yarn. Install yarn with brew install yarn if you are on mac and do the same steps in the getting-started guide, except for use yarn run ios to start app in ios simulator.
I just tried with a fresh setup that this is working perfectly fine.
Reference to yarn https://yarnpkg.com/en/
Why? Why is react looking here? I have another test android project and it also does not have react package located there, yet it runs perfectly. Why is this one looking here? The only difference is I first did setup a directory below. In MyProject/App is where i did the init. I then moved the index.js files and package.json a level up to top level directory. I want to know the WHY of this error!
Here is the error:
error: bundling: UnableToResolveError: Unable to resolve module
react/lib/ReactComponentTreeHook from /Users/Admin/Projects/MyProject/node_modules/react- native/Libraries/Performance/Systrace.js:
Module does not exist in the module map or in these directories:
/Users/Admin/Projects/MyProject/node_modules/react- native/node_modules/react/lib
, /Users/Admin/Projects/MyProject/node_modules/react/lib
This might be related to https://github.com/facebook/react-native/issues/4968
To resolve try the following:
1. Clear watchman watches: `watchman watch-del-all`.
2. Delete the `node_modules` folder: `rm -rf node_modules && npm install`.
3. Reset packager cache: rm -fr $TMPDIR/react-* or `npm start --reset-cach
All these steps I have tried. They don't fix it. I will probably do another init a level above but still I want to know whey it's looking there. Is there a module map being setup somewhere incorrectly? Where do I look for this?
UPDATE: After doing init properly in the root directory of the app I now get something else:
Loading dependency graph, done.
error: bundling: UnableToResolveError: Unable to resolve module react/lib/ReactDebugCurrentFrame from /Users/Admin/Projects/MyProjectRoot/node_modules/react-native/Libraries/Renderer/src/renderers/shared/stack/reconciler/ReactCompositeComponent.js: Module does not exist in the module map or in these directories:
This leads to suggestions that you need alpha version of react to go along with latest react:
https://github.com/facebook/react-native/issues/13017
But doing this does not work. It just leads back to the same issue I had to begin with about ReactComponentTreeHook.
Again, same suggestions about how to fix it. rm -rf node_modules followed by npm install! But I also did a npm install --save on react react-native. I think I need some response from react-native team on how to properly interpret this kind of error. What's going on here?
Xcode 8.2 still occur same error. Three lines bellow fixed it for me :)
Downgrade react(16.0.0-alpha.12 -> 16.0.0-alpha.6) & react-native(0.45.0 -> 0.44.0)
rm -rf node_modules/react
npm i react#16.0.0-alpha.6 -S
npm i react-native#0.44.0 -S
Then run react-native run-ios
Hope this help.
The problem is that the npm init, npm install --save react -react-native does not install the correct versions. What you need to do is look at the version of react inside package.json In my case it was an alpha.
So right now need to do:
npm install --save react#16.0.0-alpha.6 react-native
but check what's inside your package.json and watch any warning messages carefully
Try install react-native-git-upgrade
$ npm install -g react-native-git-upgrade
and then run
$ react-native-git-upgrade
for me it works.
This error happens when someone upgrade react-native version.
$ npm install -g react-native-git-upgrade
$ npm install react-native#latest --save
$ react-native-git-upgrade
Close all terminals.
Then clear cache. Remove directory ~/Library/Developer/Xcode/DerivedData
In Xcode, Product-> Clean
Then run simulator from Xcode or run code on the attached device again.
i am getting the below error.
The development server returned response error code: 500
URL: http://10.0.2.2:8081/index.android.bundle?platform=android&dev=true&hot=false&minify=false
Body:
{"from":"D:\AwesomeProject\index.android.js","to":"react","message":"Unable to resolve module react from D:\\AwesomeProject\\index.android.js: Module does not exist in the module map or in these directories:\n D:\AwesomeProject\node_modules\n\nThis might be related to https://github.com/facebook/react-native/issues/4968\nTo resolve try the following:\n 1. Clear watchman watches: watchman watch-del-all.\n 2. Delete the node_modules folder: rm -rf node_modules && npm install.\n 3. Reset packager cache: rm -fr $TMPDIR/react-* or npm start --reset-cache.","name":"UnableToResolveError","type":"UnableToResolveError","errors":[{}]}
onResponse
DevServerHelper.java:332
execute
RealCall.java:126
run
NamedRunnable.java:32
runWorker
ThreadPoolExecutor.java:1112
run
ThreadPoolExecutor.java:587
run
Thread.java:818
{"from":":\\AwesomeProject\\index.android.js","to":"react","message":"Unable to resolve module `react`
i tried every workaround given by the log still it's not working..
Check whether the folder named react exists inside node_modules named folder or not, and if it is not there then,
stop the server and again install 'react'
npm install react --save
after the installation please restart the sever by reseting the cache
npm start --reset-cache
Then run your application
Try
npm install
hopefully this resolve
There is a problem with the node module i had to remove the node module and add then i had to downgrade the the React-Native Library and Run the command react-native start and then react-native run-android after that it worked for me.