How to describe "object" arguments in jsdoc?

javascript jsdoc

2022-08-29 23:21:54

// My function does X and Y.
// @params {object} parameters An object containing the parameters
// @params {function} callback The callback function
function(parameters, callback) {
}

But how do I describe how the parameters object should be structured? For example it should be something like:

{
  setting1 : 123, // (required, integer)
  setting2 : 'asdf' // (optional, string)
}

答案 1

From the @param wiki page:

Parameters With Properties

If a parameter is expected to have a particular property, you can document that immediately after the @param tag for that parameter, like so:

 /**
  * @param userInfo Information about the user.
  * @param userInfo.name The name of the user.
  * @param userInfo.email The email of the user.
  */
 function logIn(userInfo) {
        doLogIn(userInfo.name, userInfo.email);
 }

There used to be a @config tag which immediately followed the corresponding @param, but it appears to have been deprecated (example here).

答案 2

By now there are 4 different ways to document objects as parameters/types. Each has its own uses. Only 3 of them can be used to document return values, though.

For objects with a known set of properties (Variant A)

/**
 * @param {{a: number, b: string, c}} myObj description
 */

This syntax is ideal for objects that are used only as parameters for this function and don't require further description of each property. It can be used for @returns as well.

For objects with a known set of properties (Variant B)

Very useful is the parameters with properties syntax:

/**
 * @param {Object} myObj description
 * @param {number} myObj.a description
 * @param {string} myObj.b description
 * @param {} myObj.c description
 */

This syntax is ideal for objects that are used only as parameters for this function and that require further description of each property. This can not be used for .@returns

For objects that will be used at more than one point in source

In this case a @typedef comes in very handy. You can define the type at one point in your source and use it as a type for or or other JSDoc tags that can make use of a type.@param@returns

/**
 * @typedef {Object} Person
 * @property {string} name how the person is called
 * @property {number} age how many years the person lived
 */

You can then use this in a tag:@param

/**
 * @param {Person} p - Description of p
 */

Or in a :@returns

/**
 * @returns {Person} Description
 */

For objects whose values are all the same type

/**
 * @param {Object.<string, number>} dict
 */

The first type (string) documents the type of the keys which in JavaScript is always a string or at least will always be coerced to a string. The second type (number) is the type of the value; this can be any type. This syntax can be used for as well.@returns

Resources

Useful information about documenting types can be found here:

https://jsdoc.app/tags-type.html

PS:

to document an optional value you can use :[]

/**
 * @param {number} [opt_number] this number is optional
 */

or:

/**
 * @param {number|undefined} opt_number this number is optional
 */