Lodash _.defaults() Method

The Lodash _.defaults() Method assign properties of source objects to the destination object for all destination properties that resolve to undefined. Source objects are applied from left to right. Once a property is set, additional values of the same property are ignored. This method mutates the object.

Syntax:

_.defaults( dest_object, [src_obj])

Parameters: This method accepts two parameters as mentioned above and described below:

• dest_object: This is the destination object.
• src_obj: These are the source objects.

Return Value: This method returns an object.

Example 1:

// Defining Lodash variable
const _ = require('lodash');

a = _.defaults({ 'gfg': 3 },
    { 'geek': 1 }, { 'gfg': 6 });

console.log(a);

Output:

{ gfg: 3, geek: 1 }

Example 2:

// Defining Lodash variable
const _ = require('lodash');

a = _.defaults({ 'a': 3 }, { 'b': 1 },
    { 'c': 5 }, { 'd': 5 }, { 'e': 5 });

console.log(a);

Output:

{ a: 3, b: 1, c: 5, d: 5, e: 5 }

Example 3:

// Defining Lodash variable
const _ = require('lodash');

a = _.defaults({ 'a': 'first setting'},
               { 'a': 'second setting but doesn't changes'});
console.log(a);

Output:

{ a: 'first setting' }

Note: This will not work in normal JavaScript because it requires the lodash library to be installed and can be installed using the following command:

npm install lodash

.