message: docs: update api reference doc for router-link-active directive
  Edits and organizes the usage information for the directive.
  PR Close
diff: @@ -19,44 +19,49 @@ import {RouterLink, RouterLinkWithHref} from './router_link';
  *
  * @description
  *
  - * Lets you add a CSS class to an element when the link's route becomes active.
  + * Tracks whether the linked route of an element is currently active, and allows you
  + * to specify one or more CSS classes to add to the element when the linked route
  + * is active.
  *
  - * This directive lets you add a CSS class to an element when the link's route
  - * becomes active.
  - *
  - * Consider the following example:
  + * Use this directive to create a visual distinction for elements associated with an active route.
  + * For example, the following code highlights the word "Bob" when the the router
  + * activates the associated route:
  *
  * ```
  * <a routerLink="/user/bob" routerLinkActive="active-link">Bob</a>
  * ```
  *
  - * When the url is either '/user' or '/user/bob', the active-link class will
  - * be added to the `a` tag. If the url changes, the class will be removed.
  + * Whenever the URL is either '/user' or '/user/bob', the "active-link" class is
  + * added to the anchor tag. If the URL changes, the class is removed.
  *
  - * You can set more than one class, as follows:
  + * You can set more than one class using a space-separated string or an array.
  + * For example:
  *
  * ```
  * <a routerLink="/user/bob" routerLinkActive="class1 class2">Bob</a>
  * <a routerLink="/user/bob" [routerLinkActive]="['class1', 'class2']">Bob</a>
  * ```
  *
  - * You can configure RouterLinkActive by passing `exact: true`. This will add the classes
  - * only when the url matches the link exactly.
  + * To add the classes only when the URL matches the link exactly, add the option `exact: true`:
  *
  * ```
  * <a routerLink="/user/bob" routerLinkActive="active-link" [routerLinkActiveOptions]="{exact:
  * true}">Bob</a>
  * ```
  *
  - * You can assign the RouterLinkActive instance to a template variable and directly check
  - * the `isActive` status.
  + * To directly check the `isActive` status of the link, assign the `RouterLinkActive`
  + * instance to a template variable.
  + * For example, the following checks the status without assigning any CSS classes:
  + *
  * ```
  * <a routerLink="/user/bob" routerLinkActive #rla="routerLinkActive">
  * Bob {{ rla.isActive ? '(already open)' : ''}}
  * </a>
  * ```
  *
  - * Finally, you can apply the RouterLinkActive directive to an ancestor of a RouterLink.
  + * You can apply the `RouterLinkActive` directive to an ancestor of linked elements.
  + * For example, the following sets the active-link class on the `<div>` parent tag
  + * when the URL is either '/user/jim' or '/user/bob'.
  *
  * ```
  * <div routerLinkActive="active-link" [routerLinkActiveOptions]="{exact: true}">
  @@ -65,9 +70,6 @@ import {RouterLink, RouterLinkWithHref} from './router_link';
  * </div>
  * ```
  *
  - * This will set the active-link class on the div tag if the url is either '/user/jim' or
  - * '/user/bob'.
  - *
  * @ngModule RouterModule
  *
  * @publicApi
  