@use JSDoc

Syntax

@callback <namepath>

Overview

The @callback tag provides information about a callback function that can be passed to other functions, including the callback's parameters and return value. You can include any of the tags that you can provide for a @method.

Once you define a callback, you can use it in the same way as a custom type defined with the @typedef tag. In particular, you can use the callback's name as a type name. This allows you to indicate that a function parameter should contain a certain type of callback.

If you want a callback to be displayed with the type definitions for a specific class, you can give the callback a namepath indicating that it is an inner function of that class. You can also define a global callback type that is referenced from multiple classes.

Examples

Documenting a class-specific callback
/**
 * @class
 */
function Requester() {}

/**
 * Send a request.
 * @param {Requester~requestCallback} cb - The callback that handles the response.
 */
Requester.prototype.send = function(cb) {
    // code
};

/**
 * This callback is displayed as part of the Requester class.
 * @callback Requester~requestCallback
 * @param {number} responseCode
 * @param {string} responseMessage
 */
Documenting a global callback
/**
 * @class
 */
function Requester() {}

/**
 * Send a request.
 * @param {requestCallback} cb - The callback that handles the response.
 */
Requester.prototype.send = function(cb) {
    // code
};

/**
 * This callback is displayed as a global member.
 * @callback requestCallback
 * @param {number} responseCode
 * @param {string} responseMessage
 */