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Lodash _.extend


Lodash is a popular library of utility functions for JavaScript. It provides a wide range of methods for developers to simplify and optimize their code. One of the most commonly used methods in Lodash is _.extend.

_.extend is a method that allows you to copy the values of all enumerable properties from one or more source objects to a target object. It takes the following syntax:

_.extend(destination, [sources])

The first argument, destination, is the target object where the properties will be copied to. The second argument, sources, is a list of one or more objects that contain the properties to be copied. The properties from the sources object(s) will be copied to the destination object in the order they are passed.

If the properties in the source object already exist in the target object, the value of the property in the target object will be overwritten with the value from the source object. If the source object has a property with the same name as a property in the target object, but the value of the source property is undefined, the target property will not be changed.

_.extend can be used for a variety of purposes, such as merging two or more objects, adding default options to a configuration object, or updating an object with new values. It is often used in conjunction with other Lodash methods to manipulate and transform objects in various ways.

Overall, _.extend is a useful and versatile method in the Lodash library that can simplify your code and make your projects more efficient.