anchor.diff:    ///  `success`,`info`, `warning`, `danger`
     @Input() String type;
   
  -  /// fired when `alert` closed with inline button or by timeout, `$event` is an instance of `Alert` component
  +  /// fired when `alert` closed with inline button or by timeout,
  +  /// `$event` is an instance of `Alert` component
     @Output() EventEmitter close = new EventEmitter ();
   
  -  /// number of milliseconds, if specified sets a timeout duration, after which the alert will be closed
  +  /// number of milliseconds, if specified sets a timeout duration,
  +  /// after which the alert will be closed
     @Input() int dismissOnTimeout;
   
     /// variable to check if the alert is closed
  
positive.code:   }
  
    /// listen when close button is pressed
    // todo: mouse event + touch + pointer
    onClose() {
      close.add(this);
      elementRef.nativeElement.remove();
      closed = true;
  
negative.code: import "package:angular2/angular2.dart";
  import 'package:node_shims/js.dart';
  
  /// Provide contextual feedback messages for typical user actions
  /// with the handful of available and flexible alert messages.
  @Component (selector: "ngbs-alert", templateUrl: 'alert.html')
  class NgBsAlert implements OnInit {
    /// provides the element reference to get native element
    ElementRef elementRef;
  
  