angular-cn/modules/angular2/src/core/metadata.ts

/**
 * This indirection is needed to free up Component, etc symbols in the public API
 * to be used by the decorator versions of these annotations.
 */

export {
  QueryMetadata,
  ContentChildrenMetadata,
  ContentChildMetadata,
  ViewChildrenMetadata,
  ViewQueryMetadata,
  ViewChildMetadata,
  AttributeMetadata
} from './metadata/di';

export {
  ComponentMetadata,
  DirectiveMetadata,
  PipeMetadata,
  InputMetadata,
  OutputMetadata,
  HostBindingMetadata,
  HostListenerMetadata
} from './metadata/directives';

export {ViewMetadata, ViewEncapsulation} from './metadata/view';

import {
  QueryMetadata,
  ContentChildrenMetadata,
  ContentChildMetadata,
  ViewChildrenMetadata,
  ViewChildMetadata,
  ViewQueryMetadata,
  AttributeMetadata
} from './metadata/di';

import {
  ComponentMetadata,
  DirectiveMetadata,
  PipeMetadata,
  InputMetadata,
  OutputMetadata,
  HostBindingMetadata,
  HostListenerMetadata
} from './metadata/directives';

import {ViewMetadata, ViewEncapsulation} from './metadata/view';
import {ChangeDetectionStrategy} from 'angular2/src/core/change_detection/change_detection';

import {
  makeDecorator,
  makeParamDecorator,
  makePropDecorator,
  TypeDecorator,
  Class
} from './util/decorators';
import {Type} from 'angular2/src/facade/lang';

/**
 * Interface for the {@link DirectiveMetadata} decorator function.
 *
 * See {@link DirectiveFactory}.
 */
export interface DirectiveDecorator extends TypeDecorator {}

/**
 * Interface for the {@link ComponentMetadata} decorator function.
 *
 * See {@link ComponentFactory}.
 */
export interface ComponentDecorator extends TypeDecorator {
  /**
   * Chain {@link ViewMetadata} annotation.
   */
  View(obj: {
    templateUrl?: string,
    template?: string,
    directives?: Array<Type | any[]>,
    pipes?: Array<Type | any[]>,
    renderer?: string,
    styles?: string[],
    styleUrls?: string[],
  }): ViewDecorator;
}

/**
 * Interface for the {@link ViewMetadata} decorator function.
 *
 * See {@link ViewFactory}.
 */
export interface ViewDecorator extends TypeDecorator {
  /**
   * Chain {@link ViewMetadata} annotation.
   */
  View(obj: {
    templateUrl?: string,
    template?: string,
    directives?: Array<Type | any[]>,
    pipes?: Array<Type | any[]>,
    renderer?: string,
    styles?: string[],
    styleUrls?: string[],
  }): ViewDecorator;
}

/**
 * {@link DirectiveMetadata} factory for creating annotations, decorators or DSL.
 *
 * ### Example as TypeScript Decorator
 *
 * ```
 * import {Directive} from "angular2/angular2";
 *
 * @Directive({...})
 * class MyDirective {
 *   constructor() {
 *     ...
 *   }
 * }
 * ```
 *
 * ### Example as ES5 DSL
 *
 * ```
 * var MyDirective = ng
 *   .Directive({...})
 *   .Class({
 *     constructor: function() {
 *       ...
 *     }
 *   })
 * ```
 *
 * ### Example as ES5 annotation
 *
 * ```
 * var MyDirective = function() {
 *   ...
 * };
 *
 * MyDirective.annotations = [
 *   new ng.Directive({...})
 * ]
 * ```
 */
export interface DirectiveFactory {
  (obj: {
    selector?: string,
    inputs?: string[],
    outputs?: string[],
    properties?: string[],
    events?: string[],
    host?: {[key: string]: string},
    bindings?: any[],
    providers?: any[],
    exportAs?: string,
    moduleId?: string,
    queries?: {[key: string]: any}
  }): DirectiveDecorator;
  new (obj: {
    selector?: string,
    inputs?: string[],
    outputs?: string[],
    properties?: string[],
    events?: string[],
    host?: {[key: string]: string},
    bindings?: any[],
    providers?: any[],
    exportAs?: string,
    moduleId?: string,
    queries?: {[key: string]: any}
  }): DirectiveMetadata;
}

/**
 * {@link ComponentMetadata} factory for creating annotations, decorators or DSL.
 *
 * ### Example as TypeScript Decorator
 *
 * ```
 * import {Component} from "angular2/angular2";
 *
 * @Component({...})
 * class MyComponent {
 *   constructor() {
 *     ...
 *   }
 * }
 * ```
 *
 * ### Example as ES5 DSL
 *
 * ```
 * var MyComponent = ng
 *   .Component({...})
 *   .Class({
 *     constructor: function() {
 *       ...
 *     }
 *   })
 * ```
 *
 * ### Example as ES5 annotation
 *
 * ```
 * var MyComponent = function() {
 *   ...
 * };
 *
 * MyComponent.annotations = [
 *   new ng.Component({...})
 * ]
 * ```
 */
export interface ComponentFactory {
  (obj: {
    selector?: string,
    inputs?: string[],
    outputs?: string[],
    properties?: string[],
    events?: string[],
    host?: {[key: string]: string},
    /* @deprecated */
    bindings?: any[],
    providers?: any[],
    exportAs?: string,
    moduleId?: string,
    queries?: {[key: string]: any},
    viewBindings?: any[],
    viewProviders?: any[],
    changeDetection?: ChangeDetectionStrategy,
    templateUrl?: string,
    template?: string,
    styleUrls?: string[],
    styles?: string[],
    directives?: Array<Type | any[]>,
    pipes?: Array<Type | any[]>,
    encapsulation?: ViewEncapsulation
  }): ComponentDecorator;
  new (obj: {
    selector?: string,
    inputs?: string[],
    outputs?: string[],
    properties?: string[],
    events?: string[],
    host?: {[key: string]: string},
    /* @deprecated */
    bindings?: any[],
    providers?: any[],
    exportAs?: string,
    moduleId?: string,
    queries?: {[key: string]: any},
    /* @deprecated */
    viewBindings?: any[],
    viewProviders?: any[],
    changeDetection?: ChangeDetectionStrategy,
    templateUrl?: string,
    template?: string,
    styleUrls?: string[],
    styles?: string[],
    directives?: Array<Type | any[]>,
    pipes?: Array<Type | any[]>,
    encapsulation?: ViewEncapsulation
  }): ComponentMetadata;
}

/**
 * {@link ViewMetadata} factory for creating annotations, decorators or DSL.
 *
 * ### Example as TypeScript Decorator
 *
 * ```
 * import {Component, View} from "angular2/angular2";
 *
 * @Component({...})
 * @View({...})
 * class MyComponent {
 *   constructor() {
 *     ...
 *   }
 * }
 * ```
 *
 * ### Example as ES5 DSL
 *
 * ```
 * var MyComponent = ng
 *   .Component({...})
 *   .View({...})
 *   .Class({
 *     constructor: function() {
 *       ...
 *     }
 *   })
 * ```
 *
 * ### Example as ES5 annotation
 *
 * ```
 * var MyComponent = function() {
 *   ...
 * };
 *
 * MyComponent.annotations = [
 *   new ng.Component({...}),
 *   new ng.View({...})
 * ]
 * ```
 */
export interface ViewFactory {
  (obj: {
    templateUrl?: string,
    template?: string,
    directives?: Array<Type | any[]>,
    pipes?: Array<Type | any[]>,
    encapsulation?: ViewEncapsulation,
    styles?: string[],
    styleUrls?: string[],
  }): ViewDecorator;
  new (obj: {
    templateUrl?: string,
    template?: string,
    directives?: Array<Type | any[]>,
    pipes?: Array<Type | any[]>,
    encapsulation?: ViewEncapsulation,
    styles?: string[],
    styleUrls?: string[],
  }): ViewMetadata;
}

/**
 * {@link AttributeMetadata} factory for creating annotations, decorators or DSL.
 *
 * ### Example as TypeScript Decorator
 *
 * ```
 * import {Attribute, Component} from "angular2/angular2";
 *
 * @Component({...})
 * class MyComponent {
 *   constructor(@Attribute('title') title: string) {
 *     ...
 *   }
 * }
 * ```
 *
 * ### Example as ES5 DSL
 *
 * ```
 * var MyComponent = ng
 *   .Component({...})
 *   .Class({
 *     constructor: [new ng.Attribute('title'), function(title) {
 *       ...
 *     }]
 *   })
 * ```
 *
 * ### Example as ES5 annotation
 *
 * ```
 * var MyComponent = function(title) {
 *   ...
 * };
 *
 * MyComponent.annotations = [
 *   new ng.Component({...})
 * ]
 * MyComponent.parameters = [
 *   [new ng.Attribute('title')]
 * ]
 * ```
 */
export interface AttributeFactory {
  (name: string): TypeDecorator;
  new (name: string): AttributeMetadata;
}

/**
 * {@link QueryMetadata} factory for creating annotations, decorators or DSL.
 *
 * ### Example as TypeScript Decorator
 *
 * ```
 * import {Query, QueryList, Component} from "angular2/angular2";
 *
 * @Component({...})
 * class MyComponent {
 *   constructor(@Query(SomeType) queryList: QueryList<SomeType>) {
 *     ...
 *   }
 * }
 * ```
 *
 * ### Example as ES5 DSL
 *
 * ```
 * var MyComponent = ng
 *   .Component({...})
 *   .Class({
 *     constructor: [new ng.Query(SomeType), function(queryList) {
 *       ...
 *     }]
 *   })
 * ```
 *
 * ### Example as ES5 annotation
 *
 * ```
 * var MyComponent = function(queryList) {
 *   ...
 * };
 *
 * MyComponent.annotations = [
 *   new ng.Component({...})
 * ]
 * MyComponent.parameters = [
 *   [new ng.Query(SomeType)]
 * ]
 * ```
 */
export interface QueryFactory {
  (selector: Type | string, {descendants}?: {descendants?: boolean}): ParameterDecorator;
  new (selector: Type | string, {descendants}?: {descendants?: boolean}): QueryMetadata;
}

export interface ContentChildrenFactory {
  (selector: Type | string, {descendants}?: {descendants?: boolean}): any;
  new (selector: Type | string, {descendants}?: {descendants?: boolean}): ContentChildrenMetadata;
}

export interface ContentChildFactory {
  (selector: Type | string): any;
  new (selector: Type | string): ContentChildFactory;
}

export interface ViewChildrenFactory {
  (selector: Type | string): any;
  new (selector: Type | string): ViewChildrenMetadata;
}

export interface ViewChildFactory {
  (selector: Type | string): any;
  new (selector: Type | string): ViewChildFactory;
}


/**
 * {@link PipeMetadata} factory for creating decorators.
 *
 * ### Example as TypeScript Decorator
 *
 * ```
 * import {Pipe} from "angular2/angular2";
 *
 * @Pipe({...})
 * class MyPipe {
 *   constructor() {
 *     ...
 *   }
 *
 *   transform(v, args) {}
 * }
 * ```
 */
export interface PipeFactory {
  (obj: {name: string, pure?: boolean}): any;
  new (obj: {name: string, pure?: boolean}): any;
}

/**
 * {@link InputMetadata} factory for creating decorators.
 *
 * See {@link InputMetadata}.
 */
export interface InputFactory {
  (bindingPropertyName?: string): any;
  new (bindingPropertyName?: string): any;
}

/**
 * {@link OutputMetadata} factory for creating decorators.
 *
 * See {@link OutputMetadata}.
 */
export interface OutputFactory {
  (bindingPropertyName?: string): any;
  new (bindingPropertyName?: string): any;
}

/**
 * {@link HostBindingMetadata} factory function.
 */
export interface HostBindingFactory {
  (hostPropertyName?: string): any;
  new (hostPropertyName?: string): any;
}

/**
 * {@link HostListenerMetadata} factory function.
 */
export interface HostListenerFactory {
  (eventName: string, args?: string[]): any;
  new (eventName: string, args?: string[]): any;
}

// TODO(alexeagle): remove the duplication of this doc. It is copied from ComponentMetadata.
/**
 * Declare reusable UI building blocks for an application.
 *
 * Each Angular component requires a single `@Component` and at least one `@View` annotation. The
 * `@Component`
 * annotation specifies when a component is instantiated, and which properties and hostListeners it
 * binds to.
 *
 * When a component is instantiated, Angular
 * - creates a shadow DOM for the component.
 * - loads the selected template into the shadow DOM.
 * - creates all the injectable objects configured with `providers` and `viewProviders`.
 *
 * All template expressions and statements are then evaluated against the component instance.
 *
 * For details on the `@View` annotation, see {@link ViewMetadata}.
 *
 * ## Lifecycle hooks
 *
 * When the component class implements some {@link angular2/lifecycle_hooks} the callbacks are
 * called by the change detection at defined points in time during the life of the component.
 *
 * ### Example
 *
 * ```
 * @Component({
 *   selector: 'greet',
 *   template: 'Hello {{name}}!'
 * })
 * class Greet {
 *   name: string;
 *
 *   constructor() {
 *     this.name = 'World';
 *   }
 * }
 * ```
 *
 */
export var Component: ComponentFactory =
    <ComponentFactory>makeDecorator(ComponentMetadata, (fn: any) => fn.View = View);

// TODO(alexeagle): remove the duplication of this doc. It is copied from DirectiveMetadata.
/**
 * Directives allow you to attach behavior to elements in the DOM.
 *
 * {@link DirectiveMetadata}s with an embedded view are called {@link ComponentMetadata}s.
 *
 * A directive consists of a single directive annotation and a controller class. When the
 * directive's `selector` matches
 * elements in the DOM, the following steps occur:
 *
 * 1. For each directive, the `ElementInjector` attempts to resolve the directive's constructor
 * arguments.
 * 2. Angular instantiates directives for each matched element using `ElementInjector` in a
 * depth-first order,
 *    as declared in the HTML.
 *
 * ## Understanding How Injection Works
 *
 * There are three stages of injection resolution.
 * - *Pre-existing Injectors*:
 *   - The terminal {@link Injector} cannot resolve dependencies. It either throws an error or, if
 * the dependency was
 *     specified as `@Optional`, returns `null`.
 *   - The platform injector resolves browser singleton resources, such as: cookies, title,
 * location, and others.
 * - *Component Injectors*: Each component instance has its own {@link Injector}, and they follow
 * the same parent-child hierarchy
 *     as the component instances in the DOM.
 * - *Element Injectors*: Each component instance has a Shadow DOM. Within the Shadow DOM each
 * element has an `ElementInjector`
 *     which follow the same parent-child hierarchy as the DOM elements themselves.
 *
 * When a template is instantiated, it also must instantiate the corresponding directives in a
 * depth-first order. The
 * current `ElementInjector` resolves the constructor dependencies for each directive.
 *
 * Angular then resolves dependencies as follows, according to the order in which they appear in the
 * {@link ViewMetadata}:
 *
 * 1. Dependencies on the current element
 * 2. Dependencies on element injectors and their parents until it encounters a Shadow DOM boundary
 * 3. Dependencies on component injectors and their parents until it encounters the root component
 * 4. Dependencies on pre-existing injectors
 *
 *
 * The `ElementInjector` can inject other directives, element-specific special objects, or it can
 * delegate to the parent
 * injector.
 *
 * To inject other directives, declare the constructor parameter as:
 * - `directive:DirectiveType`: a directive on the current element only
 * - `@Host() directive:DirectiveType`: any directive that matches the type between the current
 * element and the
 *    Shadow DOM root.
 * - `@Query(DirectiveType) query:QueryList<DirectiveType>`: A live collection of direct child
 * directives.
 * - `@QueryDescendants(DirectiveType) query:QueryList<DirectiveType>`: A live collection of any
 * child directives.
 *
 * To inject element-specific special objects, declare the constructor parameter as:
 * - `element: ElementRef` to obtain a reference to logical element in the view.
 * - `viewContainer: ViewContainerRef` to control child template instantiation, for
 * {@link DirectiveMetadata} directives only
 * - `bindingPropagation: BindingPropagation` to control change detection in a more granular way.
 *
 * ### Example
 *
 * The following example demonstrates how dependency injection resolves constructor arguments in
 * practice.
 *
 *
 * Assume this HTML template:
 *
 * ```
 * <div dependency="1">
 *   <div dependency="2">
 *     <div dependency="3" my-directive>
 *       <div dependency="4">
 *         <div dependency="5"></div>
 *       </div>
 *       <div dependency="6"></div>
 *     </div>
 *   </div>
 * </div>
 * ```
 *
 * With the following `dependency` decorator and `SomeService` injectable class.
 *
 * ```
 * @Injectable()
 * class SomeService {
 * }
 *
 * @Directive({
 *   selector: '[dependency]',
 *   inputs: [
 *     'id: dependency'
 *   ]
 * })
 * class Dependency {
 *   id:string;
 * }
 * ```
 *
 * Let's step through the different ways in which `MyDirective` could be declared...
 *
 *
 * ### No injection
 *
 * Here the constructor is declared with no arguments, therefore nothing is injected into
 * `MyDirective`.
 *
 * ```
 * @Directive({ selector: '[my-directive]' })
 * class MyDirective {
 *   constructor() {
 *   }
 * }
 * ```
 *
 * This directive would be instantiated with no dependencies.
 *
 *
 * ### Component-level injection
 *
 * Directives can inject any injectable instance from the closest component injector or any of its
 * parents.
 *
 * Here, the constructor declares a parameter, `someService`, and injects the `SomeService` type
 * from the parent
 * component's injector.
 * ```
 * @Directive({ selector: '[my-directive]' })
 * class MyDirective {
 *   constructor(someService: SomeService) {
 *   }
 * }
 * ```
 *
 * This directive would be instantiated with a dependency on `SomeService`.
 *
 *
 * ### Injecting a directive from the current element
 *
 * Directives can inject other directives declared on the current element.
 *
 * ```
 * @Directive({ selector: '[my-directive]' })
 * class MyDirective {
 *   constructor(dependency: Dependency) {
 *     expect(dependency.id).toEqual(3);
 *   }
 * }
 * ```
 * This directive would be instantiated with `Dependency` declared at the same element, in this case
 * `dependency="3"`.
 *
 * ### Injecting a directive from any ancestor elements
 *
 * Directives can inject other directives declared on any ancestor element (in the current Shadow
 * DOM), i.e. on the current element, the
 * parent element, or its parents.
 * ```
 * @Directive({ selector: '[my-directive]' })
 * class MyDirective {
 *   constructor(@Host() dependency: Dependency) {
 *     expect(dependency.id).toEqual(2);
 *   }
 * }
 * ```
 *
 * `@Host` checks the current element, the parent, as well as its parents recursively. If
 * `dependency="2"` didn't
 * exist on the direct parent, this injection would
 * have returned
 * `dependency="1"`.
 *
 *
 * ### Injecting a live collection of direct child directives
 *
 *
 * A directive can also query for other child directives. Since parent directives are instantiated
 * before child directives, a directive can't simply inject the list of child directives. Instead,
 * the directive injects a {@link QueryList}, which updates its contents as children are added,
 * removed, or moved by a directive that uses a {@link ViewContainerRef} such as a `ng-for`, an
 * `ng-if`, or an `ng-switch`.
 *
 * ```
 * @Directive({ selector: '[my-directive]' })
 * class MyDirective {
 *   constructor(@Query(Dependency) dependencies:QueryList<Dependency>) {
 *   }
 * }
 * ```
 *
 * This directive would be instantiated with a {@link QueryList} which contains `Dependency` 4 and
 * 6. Here, `Dependency` 5 would not be included, because it is not a direct child.
 *
 * ### Injecting a live collection of descendant directives
 *
 * By passing the descendant flag to `@Query` above, we can include the children of the child
 * elements.
 *
 * ```
 * @Directive({ selector: '[my-directive]' })
 * class MyDirective {
 *   constructor(@Query(Dependency, {descendants: true}) dependencies:QueryList<Dependency>) {
 *   }
 * }
 * ```
 *
 * This directive would be instantiated with a Query which would contain `Dependency` 4, 5 and 6.
 *
 * ### Optional injection
 *
 * The normal behavior of directives is to return an error when a specified dependency cannot be
 * resolved. If you
 * would like to inject `null` on unresolved dependency instead, you can annotate that dependency
 * with `@Optional()`.
 * This explicitly permits the author of a template to treat some of the surrounding directives as
 * optional.
 *
 * ```
 * @Directive({ selector: '[my-directive]' })
 * class MyDirective {
 *   constructor(@Optional() dependency:Dependency) {
 *   }
 * }
 * ```
 *
 * This directive would be instantiated with a `Dependency` directive found on the current element.
 * If none can be
 * found, the injector supplies `null` instead of throwing an error.
 *
 * ### Example
 *
 * Here we use a decorator directive to simply define basic tool-tip behavior.
 *
 * ```
 * @Directive({
 *   selector: '[tooltip]',
 *   inputs: [
 *     'text: tooltip'
 *   ],
 *   host: {
 *     '(mouseenter)': 'onMouseEnter()',
 *     '(mouseleave)': 'onMouseLeave()'
 *   }
 * })
 * class Tooltip{
 *   text:string;
 *   overlay:Overlay; // NOT YET IMPLEMENTED
 *   overlayManager:OverlayManager; // NOT YET IMPLEMENTED
 *
 *   constructor(overlayManager:OverlayManager) {
 *     this.overlay = overlay;
 *   }
 *
 *   onMouseEnter() {
 *     // exact signature to be determined
 *     this.overlay = this.overlayManager.open(text, ...);
 *   }
 *
 *   onMouseLeave() {
 *     this.overlay.close();
 *     this.overlay = null;
 *   }
 * }
 * ```
 * In our HTML template, we can then add this behavior to a `<div>` or any other element with the
 * `tooltip` selector,
 * like so:
 *
 * ```
 * <div tooltip="some text here"></div>
 * ```
 *
 * Directives can also control the instantiation, destruction, and positioning of inline template
 * elements:
 *
 * A directive uses a {@link ViewContainerRef} to instantiate, insert, move, and destroy views at
 * runtime.
 * The {@link ViewContainerRef} is created as a result of `<template>` element, and represents a
 * location in the current view
 * where these actions are performed.
 *
 * Views are always created as children of the current {@link ViewMetadata}, and as siblings of the
 * `<template>` element. Thus a
 * directive in a child view cannot inject the directive that created it.
 *
 * Since directives that create views via ViewContainers are common in Angular, and using the full
 * `<template>` element syntax is wordy, Angular
 * also supports a shorthand notation: `<li *foo="bar">` and `<li template="foo: bar">` are
 * equivalent.
 *
 * Thus,
 *
 * ```
 * <ul>
 *   <li *foo="bar" title="text"></li>
 * </ul>
 * ```
 *
 * Expands in use to:
 *
 * ```
 * <ul>
 *   <template [foo]="bar">
 *     <li title="text"></li>
 *   </template>
 * </ul>
 * ```
 *
 * Notice that although the shorthand places `*foo="bar"` within the `<li>` element, the binding for
 * the directive
 * controller is correctly instantiated on the `<template>` element rather than the `<li>` element.
 *
 * ## Lifecycle hooks
 *
 * When the directive class implements some {@link angular2/lifecycle_hooks} the callbacks are
 * called by the change detection at defined points in time during the life of the directive.
 *
 * ### Example
 *
 * Let's suppose we want to implement the `unless` behavior, to conditionally include a template.
 *
 * Here is a simple directive that triggers on an `unless` selector:
 *
 * ```
 * @Directive({
 *   selector: '[unless]',
 *   inputs: ['unless']
 * })
 * export class Unless {
 *   viewContainer: ViewContainerRef;
 *   templateRef: TemplateRef;
 *   prevCondition: boolean;
 *
 *   constructor(viewContainer: ViewContainerRef, templateRef: TemplateRef) {
 *     this.viewContainer = viewContainer;
 *     this.templateRef = templateRef;
 *     this.prevCondition = null;
 *   }
 *
 *   set unless(newCondition) {
 *     if (newCondition && (isBlank(this.prevCondition) || !this.prevCondition)) {
 *       this.prevCondition = true;
 *       this.viewContainer.clear();
 *     } else if (!newCondition && (isBlank(this.prevCondition) || this.prevCondition)) {
 *       this.prevCondition = false;
 *       this.viewContainer.create(this.templateRef);
 *     }
 *   }
 * }
 * ```
 *
 * We can then use this `unless` selector in a template:
 * ```
 * <ul>
 *   <li *unless="expr"></li>
 * </ul>
 * ```
 *
 * Once the directive instantiates the child view, the shorthand notation for the template expands
 * and the result is:
 *
 * ```
 * <ul>
 *   <template [unless]="exp">
 *     <li></li>
 *   </template>
 *   <li></li>
 * </ul>
 * ```
 *
 * Note also that although the `<li></li>` template still exists inside the `<template></template>`,
 * the instantiated
 * view occurs on the second `<li></li>` which is a sibling to the `<template>` element.
 */
export var Directive: DirectiveFactory = <DirectiveFactory>makeDecorator(DirectiveMetadata);

// TODO(alexeagle): remove the duplication of this doc. It is copied from ViewMetadata.
/**
 * Metadata properties available for configuring Views.
 *
 * Each Angular component requires a single `@Component` and at least one `@View` annotation. The
 * `@View` annotation specifies the HTML template to use, and lists the directives that are active
 * within the template.
 *
 * When a component is instantiated, the template is loaded into the component's shadow root, and
 * the expressions and statements in the template are evaluated against the component.
 *
 * For details on the `@Component` annotation, see {@link ComponentMetadata}.
 *
 * ### Example
 *
 * ```
 * @Component({
 *   selector: 'greet',
 *   template: 'Hello {{name}}!',
 *   directives: [GreetUser, Bold]
 * })
 * class Greet {
 *   name: string;
 *
 *   constructor() {
 *     this.name = 'World';
 *   }
 * }
 * ```
 */
export var View: ViewFactory =
    <ViewFactory>makeDecorator(ViewMetadata, (fn: any) => fn.View = View);

// TODO(alexeagle): remove the duplication of this doc. It is copied from AttributeMetadata.
/**
 * Metadata properties available for configuring Views.
 *
 * Each Angular component requires a single `@Component` and at least one `@View` annotation. The
 * `@View` annotation specifies the HTML template to use, and lists the directives that are active
 * within the template.
 *
 * When a component is instantiated, the template is loaded into the component's shadow root, and
 * the expressions and statements in the template are evaluated against the component.
 *
 * For details on the `@Component` annotation, see {@link ComponentMetadata}.
 *
 * ### Example
 *
 * ```
 * @Component({
 *   selector: 'greet',
 *   template: 'Hello {{name}}!',
 *   directives: [GreetUser, Bold]
 * })
 * class Greet {
 *   name: string;
 *
 *   constructor() {
 *     this.name = 'World';
 *   }
 * }
 * ```
 */
export var Attribute: AttributeFactory = makeParamDecorator(AttributeMetadata);

// TODO(alexeagle): remove the duplication of this doc. It is copied from QueryMetadata.
/**
 * Declares an injectable parameter to be a live list of directives or variable
 * bindings from the content children of a directive.
 *
 * ### Example ([live demo](http://plnkr.co/edit/lY9m8HLy7z06vDoUaSN2?p=preview))
 *
 * Assume that `<tabs>` component would like to get a list its children `<pane>`
 * components as shown in this example:
 *
 * ```html
 * <tabs>
 *   <pane title="Overview">...</pane>
 *   <pane *ng-for="#o of objects" [title]="o.title">{{o.text}}</pane>
 * </tabs>
 * ```
 *
 * The preferred solution is to query for `Pane` directives using this decorator.
 *
 * ```javascript
 * @Component({
 *   selector: 'pane',
 *   inputs: ['title']
 * })
 * class Pane {
 *   title:string;
 * }
 *
 * @Component({
 *  selector: 'tabs',
 *  template: `
 *    <ul>
 *      <li *ng-for="#pane of panes">{{pane.title}}</li>
 *    </ul>
 *    <content></content>
 *  `
 * })
 * class Tabs {
 *   panes: QueryList<Pane>;
 *   constructor(@Query(Pane) panes:QueryList<Pane>) {
 *     this.panes = panes;
 *   }
 * }
 * ```
 *
 * A query can look for variable bindings by passing in a string with desired binding symbol.
 *
 * ### Example ([live demo](http://plnkr.co/edit/sT2j25cH1dURAyBRCKx1?p=preview))
 * ```html
 * <seeker>
 *   <div #findme>...</div>
 * </seeker>
 *
 * @Component({ selector: 'foo' })
 * class seeker {
 *   constructor(@Query('findme') elList: QueryList<ElementRef>) {...}
 * }
 * ```
 *
 * In this case the object that is injected depend on the type of the variable
 * binding. It can be an ElementRef, a directive or a component.
 *
 * Passing in a comma separated list of variable bindings will query for all of them.
 *
 * ```html
 * <seeker>
 *   <div #find-me>...</div>
 *   <div #find-me-too>...</div>
 * </seeker>
 *
 *  @Component({
 *   selector: 'foo'
 * })
 * class Seeker {
 *   constructor(@Query('findMe, findMeToo') elList: QueryList<ElementRef>) {...}
 * }
 * ```
 *
 * Configure whether query looks for direct children or all descendants
 * of the querying element, by using the `descendants` parameter.
 * It is set to `false` by default.
 *
 * ### Example ([live demo](http://plnkr.co/edit/wtGeB977bv7qvA5FTYl9?p=preview))
 * ```html
 * <container #first>
 *   <item>a</item>
 *   <item>b</item>
 *   <container #second>
 *     <item>c</item>
 *   </container>
 * </container>
 * ```
 *
 * When querying for items, the first container will see only `a` and `b` by default,
 * but with `Query(TextDirective, {descendants: true})` it will see `c` too.
 *
 * The queried directives are kept in a depth-first pre-order with respect to their
 * positions in the DOM.
 *
 * Query does not look deep into any subcomponent views.
 *
 * Query is updated as part of the change-detection cycle. Since change detection
 * happens after construction of a directive, QueryList will always be empty when observed in the
 * constructor.
 *
 * The injected object is an unmodifiable live list.
 * See {@link QueryList} for more details.
 */
export var Query: QueryFactory = makeParamDecorator(QueryMetadata);

// TODO(alexeagle): remove the duplication of this doc. It is copied from ContentChildrenMetadata.
/**
 * Configures a content query.
 *
 * Content queries are set before the `ngAfterContentInit` callback is called.
 *
 * ### Example
 *
 * ```
 * @Directive({
 *   selector: 'someDir'
 * })
 * class SomeDir {
 *   @ContentChildren(ChildDirective) contentChildren: QueryList<ChildDirective>;
 *
 *   ngAfterContentInit() {
 *     // contentChildren is set
 *   }
 * }
 * ```
 */
export var ContentChildren: ContentChildrenFactory = makePropDecorator(ContentChildrenMetadata);

// TODO(alexeagle): remove the duplication of this doc. It is copied from ContentChildMetadata.
/**
 * Configures a content query.
 *
 * Content queries are set before the `ngAfterContentInit` callback is called.
 *
 * ### Example
 *
 * ```
 * @Directive({
 *   selector: 'someDir'
 * })
 * class SomeDir {
 *   @ContentChild(ChildDirective) contentChild;
 *
 *   ngAfterContentInit() {
 *     // contentChild is set
 *   }
 * }
 * ```
 */
export var ContentChild: ContentChildFactory = makePropDecorator(ContentChildMetadata);

// TODO(alexeagle): remove the duplication of this doc. It is copied from ViewChildrenMetadata.
/**
 * Configures a view query.
 *
 * View queries are set before the `ngAfterViewInit` callback is called.
 *
 * ### Example
 *
 * ```
 * @Component({
 *   selector: 'someDir',
 *   templateUrl: 'someTemplate',
 *   directives: [ItemDirective]
 * })
 * class SomeDir {
 *   @ViewChildren(ItemDirective) viewChildren: QueryList<ItemDirective>;
 *
 *   ngAfterViewInit() {
 *     // viewChildren is set
 *   }
 * }
 * ```
 */
export var ViewChildren: ViewChildrenFactory = makePropDecorator(ViewChildrenMetadata);

// TODO(alexeagle): remove the duplication of this doc. It is copied from ViewChildMetadata.
/**
 * Configures a view query.
 *
 * View queries are set before the `ngAfterViewInit` callback is called.
 *
 * ### Example
 *
 * ```
 * @Component({
 *   selector: 'someDir',
 *   templateUrl: 'someTemplate',
 *   directives: [ItemDirective]
 * })
 * class SomeDir {
 *   @ViewChild(ItemDirective) viewChild:ItemDirective;
 *
 *   ngAfterViewInit() {
 *     // viewChild is set
 *   }
 * }
 * ```
 */
export var ViewChild: ViewChildFactory = makePropDecorator(ViewChildMetadata);

// TODO(alexeagle): remove the duplication of this doc. It is copied from ViewQueryMetadata.
/**
 * Similar to {@link QueryMetadata}, but querying the component view, instead of
 * the content children.
 *
 * ### Example ([live demo](http://plnkr.co/edit/eNsFHDf7YjyM6IzKxM1j?p=preview))
 *
 * ```javascript
 * @Component({...})
 * @View({
 *   template: `
 *     <item> a </item>
 *     <item> b </item>
 *     <item> c </item>
 *   `
 * })
 * class MyComponent {
 *   shown: boolean;
 *
 *   constructor(private @Query(Item) items:QueryList<Item>) {
 *     items.onChange(() => console.log(items.length));
 *   }
 * }
 * ```
 *
 * Supports the same querying parameters as {@link QueryMetadata}, except
 * `descendants`. This always queries the whole view.
 *
 * As `shown` is flipped between true and false, items will contain zero of one
 * items.
 *
 * Specifies that a {@link QueryList} should be injected.
 *
 * The injected object is an iterable and observable live list.
 * See {@link QueryList} for more details.
 */
export var ViewQuery: QueryFactory = makeParamDecorator(ViewQueryMetadata);

// TODO(alexeagle): remove the duplication of this doc. It is copied from PipeMetadata.
/**
 * Declare reusable pipe function.
 *
 * ### Example
 *
 * ```
 * @Pipe({
 *   name: 'lowercase'
 * })
 * class Lowercase {
 *   transform(v, args) { return v.toLowerCase(); }
 * }
 * ```
 */
export var Pipe: PipeFactory = <PipeFactory>makeDecorator(PipeMetadata);

// TODO(alexeagle): remove the duplication of this doc. It is copied from InputMetadata.
/**
 * Declares a data-bound input property.
 *
 * Angular automatically updates data-bound properties during change detection.
 *
 * `InputMetadata` takes an optional parameter that specifies the name
 * used when instantiating a component in the template. When not provided,
 * the name of the decorated property is used.
 *
 * ### Example
 *
 * The following example creates a component with two input properties.
 *
 * ```typescript
 * @Component({
 *   selector: 'bank-account',
 *   template: `
 *     Bank Name: {{bankName}}
 *     Account Id: {{id}}
 *   `
 * })
 * class BankAccount {
 *   @Input() bankName: string;
 *   @Input('account-id') id: string;
 *
 *   // this property is not bound, and won't be automatically updated by Angular
 *   normalizedBankName: string;
 * }
 *
 * @Component({
 *   selector: 'app',
 *   template: `
 *     <bank-account bank-name="RBC" account-id="4747"></bank-account>
 *   `,
 *   directives: [BankAccount]
 * })
 * class App {}
 *
 * bootstrap(App);
 * ```
 */
export var Input: InputFactory = makePropDecorator(InputMetadata);

// TODO(alexeagle): remove the duplication of this doc. It is copied from OutputMetadata.
/**
 * Declares an event-bound output property.
 *
 * When an output property emits an event, an event handler attached to that event
 * the template is invoked.
 *
 * `OutputMetadata` takes an optional parameter that specifies the name
 * used when instantiating a component in the template. When not provided,
 * the name of the decorated property is used.
 *
 * ### Example
 *
 * ```typescript
 * @Directive({
 *   selector: 'interval-dir',
 * })
 * class IntervalDir {
 *   @Output() everySecond = new EventEmitter();
 *   @Output('everyFiveSeconds') five5Secs = new EventEmitter();
 *
 *   constructor() {
 *     setInterval(() => this.everySecond.emit("event"), 1000);
 *     setInterval(() => this.five5Secs.emit("event"), 5000);
 *   }
 * }
 *
 * @Component({
 *   selector: 'app',
 *   template: `
 *     <interval-dir (every-second)="everySecond()" (every-five-seconds)="everyFiveSeconds()">
 *     </interval-dir>
 *   `,
 *   directives: [IntervalDir]
 * })
 * class App {
 *   everySecond() { console.log('second'); }
 *   everyFiveSeconds() { console.log('five seconds'); }
 * }
 * bootstrap(App);
 * ```
 */
export var Output: OutputFactory = makePropDecorator(OutputMetadata);

// TODO(alexeagle): remove the duplication of this doc. It is copied from HostBindingMetadata.
/**
 * Declares a host property binding.
 *
 * Angular automatically checks host property bindings during change detection.
 * If a binding changes, it will update the host element of the directive.
 *
 * `HostBindingMetadata` takes an optional parameter that specifies the property
 * name of the host element that will be updated. When not provided,
 * the class property name is used.
 *
 * ### Example
 *
 * The following example creates a directive that sets the `valid` and `invalid` classes
 * on the DOM element that has ng-model directive on it.
 *
 * ```typescript
 * @Directive({selector: '[ng-model]'})
 * class NgModelStatus {
 *   constructor(public control:NgModel) {}
 *   @HostBinding('[class.valid]') get valid { return this.control.valid; }
 *   @HostBinding('[class.invalid]') get invalid { return this.control.invalid; }
 * }
 *
 * @Component({
 *   selector: 'app',
 *   template: `<input [(ng-model)]="prop">`,
 *   directives: [FORM_DIRECTIVES, NgModelStatus]
 * })
 * class App {
 *   prop;
 * }
 *
 * bootstrap(App);
 * ```
 */
export var HostBinding: HostBindingFactory = makePropDecorator(HostBindingMetadata);

// TODO(alexeagle): remove the duplication of this doc. It is copied from HostListenerMetadata.
/**
 * Declares a host listener.
 *
 * Angular will invoke the decorated method when the host element emits the specified event.
 *
 * If the decorated method returns `false`, then `preventDefault` is applied on the DOM
 * event.
 *
 * ### Example
 *
 * The following example declares a directive that attaches a click listener to the button and
 * counts clicks.
 *
 * ```typescript
 * @Directive({selector: 'button[counting]'})
 * class CountClicks {
 *   numberOfClicks = 0;
 *
 *   @HostListener('click', ['$event.target'])
 *   onClick(btn) {
 *     console.log("button", btn, "number of clicks:", this.numberOfClicks++);
 *   }
 * }
 *
 * @Component({
 *   selector: 'app',
 *   template: `<button counting>Increment</button>`,
 *   directives: [CountClicks]
 * })
 * class App {}
 *
 * bootstrap(App);
 * ```
 */
export var HostListener: HostListenerFactory = makePropDecorator(HostListenerMetadata);