lodash.defaults

What is lodash.defaults?

The lodash.defaults npm package is a utility that allows for the assignment of default values to properties in an object. It is particularly useful when you want to ensure that an object contains certain properties with default values if those properties are not already defined. This can be very handy in configuration objects, options for functions, or any scenario where you want to merge an object with a set of defaults.

What are lodash.defaults's main functionalities?

Assigning default values to an object

This feature allows you to assign default values from the source object to the destination object for all properties that are undefined in the destination object. In the code sample, the result will have the properties of the object with 'a' remaining as 1 (since it's already defined) and 'b' being set to 2 from the source object since 'b' is not defined in the destination object.

{"const defaults = require('lodash.defaults');\nconst object = { 'a': 1 };\nconst source = { 'a': 3, 'b': 2 };\nconst result = defaults(object, source);\nconsole.log(result); // => { 'a': 1, 'b': 2 }"}

Other packages similar to lodash.defaults

object-assign

The object-assign package is used to copy the values of all enumerable own properties from one or more source objects to a target object. It is similar to lodash.defaults but does not check if the property is undefined in the target object; it simply overwrites the properties. This makes it less suitable for default assignments but useful for merging objects.

deep-extend

deep-extend is an npm package that allows for the deep (recursive) merging of objects. Unlike lodash.defaults, which only assigns undefined properties, deep-extend can merge nested objects, making it more suitable for complex object structures where you need to merge deep properties. However, it does not specifically focus on assigning default values.

README

lodash.defaults v3.1.0

The modern build of lodash’s _.defaults exported as a Node.js/io.js module.

Installation

Using npm:

$ {sudo -H} npm i -g npm
$ npm i --save lodash.defaults

In Node.js/io.js:

var defaults = require('lodash.defaults');

See the documentation or package source for more details.