Open In App

Collect.js whenEmpty() Function

Last Updated : 13 Jun, 2022
Comments
Improve
Suggest changes
Like Article
Like
Report

Collect.js is a fluent and convenient wrapper for working with arrays and objects. The whenEmpty() function executes the callback function when the collection is empty. 

Installation: Install the Collect.js module using the following command:

npm install --save collect.js

Syntax:  

collection.whenEmpty(callback)

Parameters: This function takes only one parameter i.e. the callback function which executes if the collection is empty.

Return Value: This function returns the new collection object.

Example 1: Filename-index.js 

JavaScript
// Requiring module
const collect = require('collect.js')

// User defined collection
var myCollection = []

// Creating collection object
const collection = collect(myCollection);

// Callback execution since collection object is empty
collection.whenEmpty(item => item.push('Greetings'));

// Printing collection
console.log(collection.all());

Run the index.js file using the following command:

node index.js

Output:

[ 'Greetings' ]

Example 2: Filename-index.js 

JavaScript
// Requiring module
const collect = require('collect.js')

// User defined collection
var myCollection = ['One', 'Two', 'Three']

// Creating collection object
const collection = collect(myCollection);

// No callback execution since collection is not empty
collection.whenEmpty((item) => {
  item.push('Four')
  item.push('Five')
  item.push('Six')
});

// Printing collection
console.log(collection.all());

Run the index.js file using the following command:

node index.js

Output:

[ 'One', 'Two', 'Three']

Reference: https://collect.js.org/api/whenEmpty.html


Next Article

Similar Reads