/**
 * @decorator
 *
 * Marks a property as tracked.
 *
 * By default, a component's properties are expected to be static,
 * meaning you are not able to update them and have the template update accordingly.
 * Marking a property as tracked means that when that property changes,
 * a rerender of the component is scheduled so the template is kept up to date.
 *
 * @example
 *
 * ```typescript
 * import Component from '@glimmer/component';
 * import { tracked } from '@glimmer/tracking';
 *
 * export default class MyComponent extends Component {
 *    @tracked
 *    remainingApples = 10
 * }
 * ```
 *
 * When something changes the component's `remainingApples` property, the rerender
 * will be scheduled.
 *
 * @example Computed Properties
 *
 * In the case that you have a getter that depends on other properties, tracked
 * properties accessed within the getter will automatically be tracked for you.
 * That means when any of those dependent tracked properties is changed, a
 * rerender of the component will be scheduled.
 *
 * In the following example we have two properties,
 * `eatenApples`, and `remainingApples`.
 *
 *
 * ```typescript
 * import Component from '@glimmer/component';
 * import { tracked } from '@glimmer/tracking';
 *
 * const totalApples = 100;
 *
 * export default class MyComponent extends Component {
 *    @tracked
 *    eatenApples = 0
 *
 *    get remainingApples() {
 *      return totalApples - this.eatenApples;
 *    }
 *
 *    increment() {
 *      this.eatenApples = this.eatenApples + 1;
 *    }
 *  }
 * ```
 */
export declare let tracked: PropertyDecorator;
export declare function setPropertyDidChange(cb: () => void): void;