Collect.js unlessEmpty() Function

Collect.js is a fluent and convenient wrapper for working with arrays and objects. The unlessEmpty() function executes the callback function when the collection is not empty. 

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

npm install --save collect.js

Syntax:  

collection.unlessEmpty(callback)

Parameters: This function takes only one parameter i.e. the callback function which executes if the collection is not empty.

Return Value: This function returns the new collection object.

Example 1: Filename-index.js 

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

// User defined collection
var myCollection = [1, 2]

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

// Callback execution since collection
// object is not empty
collection.unlessEmpty(item => item.push(3));

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

Run the index.js file using the following command:

node index.js

Output:

[ 1, 2, 3 ]

Example 2: Filename-index.js 

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

// User defined collection
var myCollection = []

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

// No callback execution since
// collection is not empty
collection.unlessEmpty((item) => {
  item.push(1)
  item.push(2)
});

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

Run the index.js file using the following command:

node index.js

Output:

[ ]

Reference: https://collect.js.org/api/unlessempty