angular2/es6/prod/src/common/directives/ng_if.js

Angular 2 - a web framework for modern web apps

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};
var __metadata = (this && this.__metadata) || function (k, v) {
    if (typeof Reflect === "object" && typeof Reflect.metadata === "function") return Reflect.metadata(k, v);
};
import { Directive, ViewContainerRef, TemplateRef } from 'angular2/core';
import { isBlank } from 'angular2/src/facade/lang';
/**
 * Removes or recreates a portion of the DOM tree based on an {expression}.
 *
 * If the expression assigned to `ngIf` evaluates to a false value then the element
 * is removed from the DOM, otherwise a clone of the element is reinserted into the DOM.
 *
 * ### Example ([live demo](http://plnkr.co/edit/fe0kgemFBtmQOY31b4tw?p=preview)):
 *
 * ```
 * <div *ngIf="errorCount > 0" class="error">
 *   <!-- Error message displayed when the errorCount property on the current context is greater
 * than 0. -->
 *   {{errorCount}} errors detected
 * </div>
 * ```
 *
 * ### Syntax
 *
 * - `<div *ngIf="condition">...</div>`
 * - `<div template="ngIf condition">...</div>`
 * - `<template [ngIf]="condition"><div>...</div></template>`
 */
export let NgIf = class NgIf {
    constructor(_viewContainer, _templateRef) {
        this._viewContainer = _viewContainer;
        this._templateRef = _templateRef;
        this._prevCondition = null;
    }
    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();
        }
    }
};
NgIf = __decorate([
    Directive({ selector: '[ngIf]', inputs: ['ngIf'] }), 
    __metadata('design:paramtypes', [ViewContainerRef, TemplateRef])
], NgIf);