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Angular 2–Angular CLI

With the availability of Angular 2, I started experimenting with Angular CLI, a CLI for Angular 2 applications based on the ember-cli project. The project is still young and I encountered a lot of issues along the way.

Here are some tips and lesssons I learned:

  • Update Node to the latest LTS version(you need at least version 4 or later).
  • Run ng in a command prompt with Admin permissions
  • Be patient. The initial installation as well as ng new take a looooong time.
  • On Windows you need to run the build and serve commands with Admin permissions, otherwise the performance is awful.

Some errors I got:

  • “ng is not recognized as an internal or external command”
    • Check that %AppData%\npm is added to the PATH variable.
  • “SyntaxError: Use of const in strict mode.”
    • You are still using an older Node version that doesn’t support some of the new ES2015 features
  • “Error: Cannot find module 'exists-sync'”
    • For an unknown reason NPM still couldn’t find some packages. I installed them manually using the following command
      • npm install --save exists-sync
  • “The Broccoli Plugin: [BroccoliTypeScriptCompiler] failed with:Error: EMFILE: too many open files”
    • This happened when I tried to run ng test. As a workaround you can run ng build first and then run ng test –-watch false. This will run ng test without watching for file changes.
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