Handling angular errors

angular.errors.ts

import { Response, ResponseOptions } from '@angular/http';
class ErrorResponse extends Response implements Error {
    name: any;
    message: any;
}

export function mockError(errorResponseOpts: any) {
    return new ErrorResponse(new ResponseOptions(errorResponseOpts));
};

const response = mockError({
  body: {
   'message': 'No Such Object'
  },
  status: 404
});

// you can now use this in a service to mock an error message
return Observable.throw(response)