When I use Env in the class injected by the provider, the build fails

[FrankFSM]

//provider
public async register () {
    this.container.singleton('Adonis/App/AuthService',()=>{
      return new AuthService()
    });
  }
 
//AuthService
import Env from '@ioc:Adonis/Core/Env'

There will be an error like the above
ErrorMessage：IocLookupException: E_IOC_LOOKUP_FAILED: Cannot resolve Adonis/Core/Env namespace from the IoC Container

My solution：

//provider
 this.container.singleton('Adonis/App/AuthService',()=>{
      return new AuthService(this.container.use('Adonis/Core/Env'))
    });
//AuthService
import {Env} from '@adonisjs/env/build/src/Env'

  constructor(private env: Env) {
  }

I can solve it through the constructor, but is there a better way?

[thetutlage]

Well, the entire point of Service providers and Dependency injection is to not have hard dependencies import statements. If you don't want to use DI, then why are you even creating a service provider at first place?

[FrankFSM]

Thanks. I get it ,I didn't understand the meaning of provider