angular – 无法解析ngrx / store Action的所有参数

import { ActionReducer,Action } from '@ngrx/store'
import { StoreService } from 'ng2-storeservice'
import { IPatient,Patient } from './patient.service'

export class PatientActions {
  static ADD = '[Patient] ADD';
  static REMOVE = '[Patient] REMOVE';
  static RESET = '[Patient] RESET';

  constructor( public store: StoreService ) { }

  add( path: string,payload: IPatient ) {
    this.store.dispatch( PatientActions.ADD,payload );
  }

  remove( path: string,payload: IPatient ) {
    this.store.dispatch( PatientActions.REMOVE,payload )
  }

  reset( path: string,payload: IPatient ) {
    this.store.dispatch( PatientActions.RESET,payload )
  }
}

export const patient: ActionReducer<IPatient> = (
    state: IPatient = new Patient(),action: Action ) => {
  switch ( action.type ) {
    case PatientActions.ADD:
      return Object.assign( state,action.payload );

    case PatientActions.REMOVE:
      return Object.assign( {},state,action.payload );

    case PatientActions.RESET:
      return Object.assign( {},action.payload );

    default:
      return state;
  }
};

服务适当地放置在可识别的模块中.
运行该应用程序会出现以下错误

metadata_resolver.js:499Uncaught Error: Can't resolve all parameters for PatientActions: (?).
    at CompileMetadataResolver.getDependenciesMetadata (http://localhost:4200/main.bundle.js:31019:19)
    at CompileMetadataResolver.getTypeMetadata (http://localhost:4200/main.bundle.js:30920:26)
    at http://localhost:4200/main.bundle.js:31063:41
    at Array.forEach (native)
    at CompileMetadataResolver.getProvidersMetadata (http://localhost:4200/main.bundle.js:31043:19)
    at http://localhost:4200/main.bundle.js:30741:71
    at Array.forEach (native)
    at CompileMetadataResolver.getNgModuleMetadata (http://localhost:4200/main.bundle.js:30732:44)
    at http://localhost:4200/main.bundle.js:30745:50
    at Array.forEach (native)

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