Error: Can't resolve all parameters for ApplicationModule: (?)

Question

I want to create Angular application without CLI. After that I get an error:

Error: Can\'t resolve all parameters for ApplicationModule: (?).

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Answer 1

1. Install core-js by command:

   npm i core-js
   

2. Add in main.ts file:

   import 'core-js/es6/reflect';
   import 'core-js/es7/reflect';
   

Btw. I have spent a whole day to resolve this.