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@callback

Syntax​

@callback CallbackName

Overview​

@callback defines a named function type (a callback signature) that can be referenced from @param and @type. It works like @typedef but is specifically designed for function types. After defining the callback, use @param and @returns within the same block to describe the callback's parameters and return value.

TypeScript Supported

TypeScript uses @callback to define named function types in JavaScript files.

TypeScript docs →

Example​

/**
 * @callback RequestCallback
 * @param {Error|null} err - An error, or null on success.
 * @param {Object} response - The response data.
 */

/**
 * Sends a network request.
 * @param {string} url - The endpoint URL.
 * @param {RequestCallback} callback - Called when the request completes.
 */
function request(url, callback) {}

Namespaced callback​

Attach the callback to a module or namespace to avoid name collisions:

/**
 * @callback module:net~RequestCallback
 * @param {Error|null} err
 * @param {Object} data
 */

See also​

Official reference: jsdoc.app/tags-callback