/**
* @license
* Copyright The Closure Library Authors.
* SPDX-License-Identifier: Apache-2.0
*/
goog.provide('goog.pubsub.TopicId');
/**
* A templated class that is used to register `goog.pubsub.PubSub`
* subscribers.
*
* Typical usage for a publisher:
* <code>
* /** @type {!goog.pubsub.TopicId<!zorg.State>}
* zorg.TopicId.STATE_CHANGE = new goog.pubsub.TopicId(
* goog.events.getUniqueId('state-change'));
*
* // Compiler enforces that these types are correct.
* pubSub.publish(zorg.TopicId.STATE_CHANGE, zorg.State.STARTED);
* </code>
*
* Typical usage for a subscriber:
* <code>
* // Compiler enforces the callback parameter type.
* pubSub.subscribe(zorg.TopicId.STATE_CHANGE, function(state) {
* if (state == zorg.State.STARTED) {
* // Handle STARTED state.
* }
* });
* </code>
*
* @param {string} topicId
* @template PAYLOAD
* @constructor
* @final
* @struct
*/
goog.pubsub.TopicId = function(topicId) {
'use strict';
/**
* @const
* @private
*/
this.topicId_ = topicId;
};
/** @override */
goog.pubsub.TopicId.prototype.toString = function() {
'use strict';
return this.topicId_;
};