import { InjectionToken } from '@angular/core' ; import { Feedback , AddedWord } from './entities/feedback' ; export interface IFeedbackService { sendFeedback ( feedback ) : Promise < any > ; addWord ( word ) : Promise < any > ; } export const FEEDBACK_SERVICE = new InjectionToken < IFeedbackService > ( 'Feedback service' ) ; export const FEEDBACK_CONFIG = new InjectionToken < any > ( 'Feedback service config' ) ;