How to fix Cannot find module 'typescript' in Angular 4?
Javascriptnode.jsAngularJavascript Problem Overview
I generated Angular 4 app 3 weeks ago using the @angular/cli. After 2 weeks, I tried to run it with the command line ng serve but I am prompted an error below:
Cannot find module 'typescript'
Error: Cannot find module 'typescript'
at Function.Module._resolveFilename (module.js:469:15)
at Function.Module._load (module.js:417:25)
at Module.require (module.js:497:17)
at require (internal/module.js:20:19)
at Object.<anonymous> (C:\Users\mypc\Documents\Angular Projects\my-angular-app\node_modules\@angular\cli\models\config\config.js:5:12)
at Module._compile (module.js:570:32)
at Object.Module._extensions..js (module.js:579:10)
at Module.load (module.js:487:32)
at tryModuleLoad (module.js:446:12)
at Function.Module._load (module.js:438:3)
Do you have any idea how to fix this? Thanks.
Javascript Solutions
Solution 1 - Javascript
For me just running the below command is not enough (though a valid first step):
npm install -g typescript
The following command is what you need (I think deleting node_modules works too, but the below command is quicker)
npm link typescript
Solution 2 - Javascript
This should do the trick,
npm install -g typescript
Solution 3 - Javascript
I was able to solve this problem by removing node_modules then running npm install
Solution 4 - Javascript
I had a similar problem when I rearranged the folder structure of a project. I tried all the hints given in this thread but none of them worked. After checking further I discovered that I forgot to copy an important hidden file over to the new directory. That was
> .angular-cli.json
from the root directory of the @angular/cli project. After I copied that file over all was running as expected.
Solution 5 - Javascript
If you don't have particular needs, I suggest to install Typescript locally.
NPM Installation Method
npm install --global typescript # Global installation
npm install --save-dev typescript # Local installation
Yarn Installation Method
yarn global add typescript # Global installation
yarn add --dev typescript # Local installation
Solution 6 - Javascript
Run: npm link typescript if you installed globally
But if you have not installed typescript try this command: npm install typescript
Solution 7 - Javascript
If you use yarn instead of npm, you can install typescript package for that workspace by running:
yarn add typescript
or you can install it globally by running:
sudo yarn global add typescript
to be available for any project.
Solution 8 - Javascript
I had the same problem. If you have installed first nodejs by apt and then you use the tar.gz from nodejs.org, you have to delete the folder located in /usr/lib/node_modules.
Solution 9 - Javascript
I had a very similar problem after moving a working project to a new subdirectory on my file system. It turned out I had failed to move the file named .angular-cli.json to the subfolder along with everything else. After noticing that and moving the file into the subdirectory, all was back to normal.
Solution 10 - Javascript
Run 'npm install' it will install all necessary pkg .
Solution 11 - Javascript
If you have cloned your project from git or somewhere then first, you should type npm install.
Solution 12 - Javascript
The best way is to do: npm install or npm i
this way all dependencies will be added.
Solution 13 - Javascript
I had this same problem using npm run start-dev as configured my package.json ("start-dev": "nodemon src/index.ts"). When i used nodemon src/index.ts in cmd work just fine, but to use npm run start-dev i had to use npm link typescript, it solve the problem.