Uncaught reflect-metadata shim is required when using class decorators

OS? Windows 7, 8 or 10. Linux (which distribution). Mac OSX (Yosemite? El Capitan?) El Capitan

Versions. Please run ng --version. If there’s nothing outputted, please run in a Terminal: node --version and paste the result here:

angular-cli: 1.0.0-beta.11-webpack.2 node: 4.4.2 os: darwin x64

Repro steps. Was this an app that wasn’t created using the CLI? What change did you do on your code? etc.

1. Start a project with Angular CLI (Webpack)

2. Create a standalone class (e.g. a model) with an EventEmitter property.

3. When new EventEmitter<...>() is called in that class, this error shows on the browser console.

   Uncaught reflect-metadata shim is required when using class decorators

The log given by the failure. Normally this include a stack trace and some more information.

All I see is:

Uncaught reflect-metadata shim is required when using class decorators / output_ast.js:334

Mention any other details that might be useful.

This works fine in a non-webpack setting, like here:

http://plnkr.co/edit/255WLWdkSnZdMfNvCk3I?p=preview

That Plunkr works and shows what I am trying to do. The problem is when I do this exact same thing when using Webpack.

Also, EventEmitter works just fine if used in a component.

I am not sure whether this is a bug or user error. Please apologize me if it’s the latter.

Thanks in advance!

[griga]

I had the same issue when i’ve migrated to angular-cli’s github master branch from npm version

while doing ng init to update angular-cli generated files, i’ve missed import "./polyfills.ts"; on top of main.ts file

adding this line fixed my problem

[cmermingas]

Absolutely. I’ll put something together and upload the repo here this week.