import { CdkPortal } from '@angular/cdk/portal' ; import { Directive , InjectionToken } from '@angular/core' ; /**
 * Injection token that can be used to reference instances of `SbbTabLabel`. It serves as
 * alternative token to the actual `SbbTabLabel` class which could cause unnecessary
 * retention of the class and its directive metadata.
 */ export const SBB_TAB_LABEL = new InjectionToken < SbbTabLabel > ( 'SbbTabLabel' ) ; /** Used to flag tab labels for use with the portal directive */ @ Directive ( { selector : '[sbb-tab-label], [sbbTabLabel]' , providers : [ { provide : SBB_TAB_LABEL , useExisting : SbbTabLabel } ] , } ) export class SbbTabLabel extends CdkPortal { }