refactor(directives): minor cleanup & refactoring

Closes angular#3629

Author: vicb

modules/angular2/src/directives/ng_if.ts

@@ -26,23 +26,17 @@ import {isBlank} from 'angular2/src/facade/lang';
  */
 @Directive({selector: '[ng-if]', properties: ['ngIf']})
 export class NgIf {
- viewContainer: ViewContainerRef;
- templateRef: TemplateRef;
- prevCondition: boolean;
+ private _prevCondition: boolean = null;
 
- constructor(viewContainer: ViewContainerRef, templateRef: TemplateRef) {
- this.viewContainer = viewContainer;
- this.prevCondition = null;
- this.templateRef = templateRef;
- }
+ constructor(private _viewContainer: ViewContainerRef, private _templateRef: TemplateRef) {}
 
  set ngIf(newCondition /* boolean */) {
- if (newCondition && (isBlank(this.prevCondition) || !this.prevCondition)) {
- this.prevCondition = true;
- this.viewContainer.createEmbeddedView(this.templateRef);
- } else if (!newCondition && (isBlank(this.prevCondition) || this.prevCondition)) {
- this.prevCondition = false;
- this.viewContainer.clear();
+ if (newCondition && (isBlank(this._prevCondition) || !this._prevCondition)) {
+ this._prevCondition = true;
+ this._viewContainer.createEmbeddedView(this._templateRef);
+ } else if (!newCondition && (isBlank(this._prevCondition) || this._prevCondition)) {
+ this._prevCondition = false;
+ this._viewContainer.clear();
  }
  }
 }

modules/angular2/src/directives/ng_switch.ts

@@ -1,21 +1,17 @@
 import {Directive} from 'angular2/annotations';
 import {Host} from 'angular2/di';
 import {ViewContainerRef, TemplateRef} from 'angular2/core';
-import {isPresent, isBlank, normalizeBlank} from 'angular2/src/facade/lang';
-import {ListWrapper, List, MapWrapper, Map} from 'angular2/src/facade/collection';
+import {isPresent, isBlank, normalizeBlank, CONST_EXPR} from 'angular2/src/facade/lang';
+import {ListWrapper, List, Map} from 'angular2/src/facade/collection';
 
-export class SwitchView {
- _viewContainerRef: ViewContainerRef;
- _templateRef: TemplateRef;
+const _WHEN_DEFAULT = CONST_EXPR(new Object());
 
- constructor(viewContainerRef: ViewContainerRef, templateRef: TemplateRef) {
- this._templateRef = templateRef;
- this._viewContainerRef = viewContainerRef;
- }
+export class SwitchView {
+ constructor(private _viewContainerRef: ViewContainerRef, private _templateRef: TemplateRef) {}
 
- create() { this._viewContainerRef.createEmbeddedView(this._templateRef); }
+ create(): void { this._viewContainerRef.createEmbeddedView(this._templateRef); }
 
- destroy() { this._viewContainerRef.clear(); }
+ destroy(): void { this._viewContainerRef.clear(); }
 }
 
 /**
@@ -45,16 +41,10 @@ export class SwitchView {
  */
 @Directive({selector: '[ng-switch]', properties: ['ngSwitch']})
 export class NgSwitch {
- _switchValue: any;
- _useDefault: boolean;
- _valueViews: Map<any, List<SwitchView>>;
- _activeViews: List<SwitchView>;
-
- constructor() {
- this._valueViews = new Map();
- this._activeViews = [];
- this._useDefault = false;
- }
+ private _switchValue: any;
+ private _useDefault: boolean = false;
+ private _valueViews: Map<any, List<SwitchView>> = new Map();
+ private _activeViews: List<SwitchView> = [];
 
  set ngSwitch(value) {
  // Empty the currently active ViewContainers
@@ -65,7 +55,7 @@ export class NgSwitch {
  var views = this._valueViews.get(value);
  if (isBlank(views)) {
  this._useDefault = true;
- views = normalizeBlank(this._valueViews.get(_whenDefault));
+ views = normalizeBlank(this._valueViews.get(_WHEN_DEFAULT));
  }
  this._activateViews(views);
 
@@ -91,7 +81,7 @@ export class NgSwitch {
  // Switch to default when there is no more active ViewContainers
  if (this._activeViews.length === 0 && !this._useDefault) {
  this._useDefault = true;
- this._activateViews(this._valueViews.get(_whenDefault));
+ this._activateViews(this._valueViews.get(_WHEN_DEFAULT));
  }
  }
 
@@ -123,18 +113,17 @@ export class NgSwitch {
  }
 
  _deregisterView(value, view: SwitchView): void {
- // `_whenDefault` is used a marker for non-registered whens
- if (value == _whenDefault) return;
+ // `_WHEN_DEFAULT` is used a marker for non-registered whens
+ if (value === _WHEN_DEFAULT) return;
  var views = this._valueViews.get(value);
  if (views.length == 1) {
- MapWrapper.delete(this._valueViews, value);
+ this._valueViews.delete(value);
  } else {
  ListWrapper.remove(views, view);
  }
  }
 }
 
-
 /**
  * Defines a case statement as an expression.
  *
@@ -152,27 +141,21 @@ export class NgSwitch {
  */
 @Directive({selector: '[ng-switch-when]', properties: ['ngSwitchWhen']})
 export class NgSwitchWhen {
- _value: any;
- _switch: NgSwitch;
+ // `_WHEN_DEFAULT` is used as a marker for a not yet initialized value
+ _value: any = _WHEN_DEFAULT;
  _view: SwitchView;
 
  constructor(viewContainer: ViewContainerRef, templateRef: TemplateRef,
- @Host() sswitch: NgSwitch) {
- // `_whenDefault` is used as a marker for a not yet initialized value
- this._value = _whenDefault;
- this._switch = sswitch;
+ @Host() private _switch: NgSwitch) {
  this._view = new SwitchView(viewContainer, templateRef);
  }
 
- onDestroy() { this._switch; }
-
  set ngSwitchWhen(value) {
  this._switch._onWhenValueChanged(this._value, value, this._view);
  this._value = value;
  }
 }
 
-
 /**
  * Defines a default case statement.
  *
@@ -188,8 +171,6 @@ export class NgSwitchWhen {
 export class NgSwitchDefault {
  constructor(viewContainer: ViewContainerRef, templateRef: TemplateRef,
  @Host() sswitch: NgSwitch) {
- sswitch._registerView(_whenDefault, new SwitchView(viewContainer, templateRef));
+ sswitch._registerView(_WHEN_DEFAULT, new SwitchView(viewContainer, templateRef));
  }
 }
-
-var _whenDefault = new Object();